By Dr J Floor Anthoni (2001)
To save the sea is quite different from saving
wildlife on land. The sea is such a unique place, so strange, and
most of it has been left relatively undisturbed. Marine reserves are one
of the ways to reduce threats to the sea. To create a marine reserve should
be easy, but our ignorance of the sea and how to protect it, has caused
some failures from which we should learn. Learn to do the right things
for the right reasons. Unfortunately the science of marine conservation
is replete with untested myths and fallacies that prevent us from finding
the right solutions.
An historical perspective. Factors in terrestrial and marine conservation.
The results of 25 years of active marine conservation in NZ. Heavy rain,
the new threat. Degraded and degrading marine reserves.
Frequently Asked Questions
about marine reserves, with honest and incisive answers. (23 p)
Myths and Fallacies in
speeches and newspaper articles, dissected by Floor Anthoni (large)
From hunter to caretaker: an
article about marine conservation, containing the essence of this chapter,
and with discussion points at the end (19 p, needs updating)
Threats: a summary of threats
to humans, land, soil, water and air. (20 p)
Realms: a summary of the most
important ecological realms: land, soil, fresh water and seas. (4 p)
an introduction to marine habitats and their strange living conditions.
geology, fertility, sustainability, degradation, erosion and conservation.
Marine reserves are
not working. Why hurry? A press article written by Floor Anthoni, Jan
Fishing: a chapter about
fishing, whaling, overfishing and fishing regulation (planned)
Global warming: a chapter
about the mechanisms of global warming and its consequences. (planned)
El Niño: a chapter
about the mechanism of the El Niño weather phenomenon. (planned)
Pew Oceans Commission (www.pewoceans.org)
is an independent group of American leaders conducting a national dialogue
on the policies needed to restore and protect living marine resources in
US waters. It will report to Congress in 2002. Several good reports available.
UNEP-GPA Global Programme for Action (http://www.gpa.unep.org/):
fighting marine pollution from land-based activities (extensive).
SPREP - South Pacific Regional Environment Programme
action in the South Pacific. Promoting co-operation. (incomplete)
UN WSSD - World Summit on Sustainable Development
progress in implementing sustainable development has been extremely disappointing
since the 1992 Earth Summit, with poverty deepening and environmental degradation
worsening. What the world wanted, the General Assembly said, was not a
new philosophical or political debate but rather, a summit of actions and
results. Was this achieved?
The Seafriends web site is dedicated
to the preservation of our oceans and the world in general. It does so
by looking at all aspects of our problems and how to understand these.
Only by the process of understanding, and by being strictly honest, can
each of us contribute with what he can do best. We are not greenies who
wish to push our beliefs onto others, but we want common sense to prevail.
We can see how and when marine reserves fail, and unfortunately we have
seen many such failures. We understand the limitations of marine reserves.
Only by being honest and by understanding our mistakes, can we hope to
progress to better solutions that will work and will keep working. Unfortunately,
we have often been brushed off as anti-conservationists, or being against
marine reserves. Nothing could be further from the truth. This 'controversial'
chapter therefore, should be read with care, since (hopefully) it forms
the basis for policies towards better marine conservation. There are so
many zealous conservationists travelling the globe while lecturing and
writing about marine reserves, which they have never visited under water
themselves. This chapter was written by someone with over 2000 dives inside
and outside many marine reserves.
The literature on marine
reserves is prolific, since anyone can make a contribution. It disappointed
me that it took a year longer than planned, to write this chapter. It is
an indictment of science that so much pure opinion is being published and
so little hard fact. In fact, a new discipline is about to be born, leaving
the public out of the field. I have therefore tried to distil all important
thoughts and facts, so that nothing important has been left out. In this
way you can learn what matters in a short while, to play your role in marine
conservation, with what you can do best.
Although marine conservation
and marine reserves have international importance, most of this section
will be illustrated with the New Zealand situation, partly because that
is what I am familiar with, and partly because New Zealand wishes to lead
the way in this aspect of human endeavour.
Floor Anthoni, December 2002.
Note! for best printed results, set your page up with
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The sea is a large body. Not only is it vast, covering nearly three quarters
of the globe, but it is also deep. As opposed to the terrestrial habitat,
which is smeared over the surface of continents in a layer no more than
40 metres thick (and effectively much less), the sea is 4000m deep on average,
with places descending to 10km. The sea is also a very different kind of
habitat, almost unimaginably different from the terrestrial world we know
so well. It is a hostile place, impossible to travel to by foot or automobile,
and even by boat, can be very unpleasant. Please read about this in biodiversity/marine.
The sea is not inhabited by people and therefore does not suffer the consequences
of extensive habitat change (forests into pastures), habitation (cities
and roads), and whatever civilisation has wrought (extraction and pollution
of various kinds). One would thus be tempted to ask whether the sea needs
conserving at all.
The seas have always been a dependable provider of protein-rich food, to
the extent that as recently as fifty years ago, the oceans were thought
to be able to provide all the food humanity needs. However, in recent times,
the inexhaustible bounties of the sea have shown their limits. Fisheries
everywhere in the world have either reached their limits or have collapsed.
In all, our report card for managing the oceans, does not look good. But
it has not been for lack of trying. Most nations have established controls
over their inland and marine fisheries a long time ago, in order to protect
them from overexploitation. The recent creation of Exclusive Economic Zones
(EEZ) around fishing nations, is yet another tool in the toolkit of marine
conservation. So, what are the current threats to our seas and what are
our tools to manage these?
As the world population increases at its fastest
rate ever, the sea experiences a very sudden increase in stresses, some
old and some new:
exploitation: fishing in all its forms is
an old use of the seas, but we have become so good at it, that our efficiency
threatens almost every habitat in the sea, down to 800m deep. Fishing arises
from our need for food, but recently also for non-food items such as shells
for collectors, fish and invertebrates for aquariums, and so on. In tropical
seas almost every species living in the sea has been exploited to excess.
competing with humans for food: due to technology
and cheap fossil energy, we are able to fish far more effectively than
any other creature on earth. In doing so, we out-compete them, resulting
in a decline of top predators like bass, sharks, dolphins and some whales.
soil erosion: although erosion is a natural
process, humans have increased it by 10-100 times. With huge earth-moving
machines, Man creates comfort around him for habitation, industry and roads.
Being at the bottom of civilisation, everything Man does, results in some
effluent reaching the sea. Soils contain the fertility of our land, and
this is washed into the sea, resulting in disastrous loss of life, especially
close to the coast, where most biodiversity occurs.
nutrient discharge: although our society speaks
in terms of recycling, the most precious of all substances, our sewage,
is not recycled. After 'treatment', it flows into the sea where it fertilises
the water, causing dense and poisonous plankton blooms. As farms become
more intensified (see the chapter on soil/fertility),
they leach more of their fertilisers into waterways and into the sea, with
similar effect. When the plankton blooms densely, most of it sinks to deeper
water to be decomposed, requiring oxygen. As these blooms also obscure
the light from penetrating the depth (which allows the production of oxygen
by plants), the sea may become anoxic (lacking oxygen). Huge dead-zones
are now found in many places.
chemical pollution: society has become more
and more dependent on chemicals of all kinds, from perfumes to fertiliser.
The ones used in large quantities, while having the most profound and lasting
effects (biocides, hormones, fuel additives, heavy metals) are also the
most damaging to nature. Eventually they end up in the coastal zone, where
they become diluted by the large water mass of the ocean. However, marine
creatures have evolved in an environment of scarcity, which has endowed
many with the ability to concentrate scarce substances inside their bodies.
Particularly planktonic organisms do so, and those feeding on them. Through
this path, chemicals become concentrated once again, this time to kill
top predators first (birds, dolphins, fish for human consumption) and people
oil: many oils are liquid and gaseous hydrocarbons
of geological origin. While some oils are naturally occurring, most arise
from human activity: refined petroleum products or their derivatives (exploration,
exploitation, transport, use). Some oils are volatile or easily degraded
and disappear rapidly from aquatic systems, but some may persist in the
water column or in sediments. Oils may be toxic to aquatic life when ingested
or absorbed through skin or gills, interfere with respiratory systems,
foul fur and feathers, smother aquatic communities, habitats and bathing
beaches, taint seafood and contaminate water supplies. However, being a
natural product, nature is able to undo oil spills surprisingly quickly.
Sensitive areas are sheltered coasts with high tidal ranges; estuaries;
cold places where biological activity is low and oils become thick.
exotic species introduction & marine farms:
while spreading across continents, the human race has spread many of its
favourite species like crops and domestic animals, but also diseases. Very
recently Man has systematically spread almost every species of plant to
every continent, not for food but for pleasing appearances in his gardens.
He has also spread many animal species for similar reasons. As a result,
most places in the world now look very much like one another, and will
become more so in the future. The sea has relatively been spared these
destructive influences. The seas have also always been interconnected more
than the land masses. As a result, each island or continent has few endemic
species that occur only there and nowhere else. But oceans have their barriers
to the wanton spread of organisms. However, these are now crossed by ships,
with organisms clinging to their hulls and inside their ballast waters.
Not surprisingly, marine species have unknowingly and unintentionally been
spread to places where they do not belong. Some have been able to reproduce
successfully, making a nuisance of themselves in their new home sea, to
the detriment of endemic species. Marine farms add another dimension by
their possible release of alien species, in-bred genes or disease. However,
compared to the wilful introduction of alien species on land, the sea has
largely been spared.
disturbance: the seas have been spared the
planned and wholesale disturbance of agriculture and urbanisation, but
nets are trawled over bottoms that are at times not sand or mud, but rocky
platforms full of slow growing life forms. Also during mining operations,
particularly the extraction of sand, benthic (bottom) marine communities
can be disturbed. However, overall, this is substantially less than what
Man has done to his land.
debris pollution: we are supposed to recycle
our wastes, or at least dispose of them in an environmentally friendly
way. It is not at all difficult to do, but in the process of working with
the sea, nets are lost. These keep catching fish for a while (ghost nets),
until they become rolled up by storms or decay spontaneously. Likewise,
lobster pots and other fish catching gear is lost. Not long ago, fishermen
ditched anything no longer of use, over board. It is still practised by
almost all large ships on the open seas, believing that rubbish can do
no harm at 3km depth, but progress has been made towards curbing this practice.
Floatable plastics disperse over large distances, only to land on some
other country's beaches. However, nature has its ways of disposing of our
rubbish: aluminium cans disintegrate within 10 years; reefs grow over rubbish
in shallow water; sea water is highly corrosive, eating away at steel,
aluminium, wood and other materials. In general, rubbish does not significantly
impact on marine environments.
global climate change: clear signs have presented
themselves that the climate is changing globally due to the side effects
of human existence. As a result, some areas become drier, others wetter,
but this won't affect the seas very much. Some places become warmer, others
cooler. This is detrimental to many natural forests, because they cannot
move easily. The sea is very much less affected by such changes, because
marine organisms can move freely over large distances (their larvae), and
many habitats are contiguous or interconnected. The sea is also more moderate
in its extremes of temperature.
pathogen discharge: disease-causing organisms
(pathogens) are found all around, in every drop of water. The ones we fear
are those able to cause disease in humans, and it is no surprise that these
are spread by humans. However, it is not likely that human pathogens (e.g.
in sewage) will have a noticeable effect on other organisms.
nuclear wastes: nuclear wastes are a new possible
threat to oceans, particularly when oil runs out and nuclear energy is
again considered an alternative. The deep bottom of the oceans has always
looked attractive for dumping nuclear wastes. Radioactive elements can
be concentrated by marine organisms, returning to the food chain where
it can possibly harm humans. However, the oceans are a very large body
of water, with a background level of radiation always present. For humans
to increase this noticeably, the way they have increased carbondioxide
in air, requires an awful lot of free radioactive nuclei. Furthermore,
most nuclear fuel and waste is insoluble and has a low level of radioactivity.
heavy metals: heavy metals are natural constituents
of the Earth's crust. Human activities have drastically altered the biochemical
and geochemical cycles and balance of some heavy metals. Heavy metals are
stable and persistent environmental contaminants since they cannot be degraded
or destroyed. Therefore, they tend to accumulate in the soils and sediments.
They remain captured above the continental shelves. Excessive levels of
metals in the marine environment can affect marine biota and pose risk
to human consumers of seafood. Sources of these are: mining, foundries,
smelters, manufacturing, piping, dredging, traffic, volcanic activity.
Heavy metals include lead, mercury, cadmium and others.
habitat loss and fragmentation: see disturbance
In the summary above, the most pressing threats to
the sea are by far: overfishing, soil erosion and nutrient discharge. Whereas
overfishing has its natural limits (you stop fishing when there is no more
fish), soil erosion and nutrient discharge appear to be limitless, and
they are increasing rapidly. Read about soil
erosion on this web site.
and effects The diagram shown here sums
up the most important threats to the sea, what causes them, and what effects
they have on the marine environment. In brown the main products from civilisation:
mud, nutrients, poisons and debris.
When cuts are made in the
land, either by ploughing, roading, development and dwellings, heavy erosion
follows. The mud, and particularly its finest particles, the clay, cannot
be stopped by sedimentation ponds or other inventions, and it flows unhindered
into the sea, where it releases its nutrients. Nutrients from overfertilised
farm soils, and farm animal dung, are washed into the sea without
becoming part of the soil chemistry. Sewage from human settlements, treated
or not, cause heavy loads of nutrients to enter the sea near human settlements.
Nutrients in the sea cause
plankton blooms, and when these exceed what is normal (eutrophication),
the plankton ecosystems become impaired, leading to unwanted effects like
obscuring the light, thereby killing seaweeds. Diatoms in the plankton
can join together in strings, forming suffocating mats. These can kill
burrowing clams, and sessile filterfeeders like seasquirts, bryozoans and
sponges. Some mats of blue-green algae can kill grazers such as sea urchins
Impaired plankton ecosystems
can lead to concentrations of highly poisonous plankton organisms (mostly
causing direct mortality of planktonic organisms like shrimps and larvae
of many kind, and those feeding on these in the planktonic food chain.
It leads to mass mortality of fish of all kind, but it spares those feeding
solely on plants. It can also kill sessile organisms like sponges.
With the sewage and stormwater,
come a large number of chemicals, used in household and industry. Many
of these are poisonous, causing slow kill by being accumulated slowly in
The main effect of fishing
is that mature fish are taken from the marine ecosystem, often by targeting
specific species. In doing so, the ecosystem can become unbalanced, with
the loss of large fish of some species, while small fish of other species
are able to increase their numbers. Trawling also ploughs the sea bottom,
which could lead to the destruction of sensitive benthic (bottom) communities.
However, the sea bottom is extremely flat and not prone to 'erosion', while
also its soil organisms are used to large scale disturbance by storms.
Debris from fishing and marine
transport are often ditched overboard, soiling the marine environment and
snagging marine life. However, this threat is very small compared to those
diagram shows how seemingly innocent loss of light will degrade the marine
environment profoundly. The image shows three cross-sections of a rocky
shore. The leftmost is a healthy environment in clear water. There are
four distinct habitat zones: the bladderkelp zone in the wave-washed surface
waters, the barren urchin-grazed zone underneath, followed by a closed-canopy
kelp forest. Beyond where the kelp can no longer grow through lack of sunlight,
extends the deep reef habitat, represented by filter-feeding organisms
As the water clarity decreases,
all zones move up, and their total extent decreases. This is accompanied
by the loss of many species, particularly those sensitive to poor water
quality (like filter-feeders), but also many species of fish and plant.
The kelp canopy opens up. Biodiversity and biomass decrease.
As the water becomes filthier
still, the environment contracts further and different plants take the
place of the kelp. The deep reef community disappears. Beneath all this
extends a barren zone, covered in silt. The marine environment can barely
can be formed in the sea where large amounts of mud and nutrients flow
into the sea, such as at the mouth of a river with a large modified catchment
area. The water contains mud and nutrients from agriculture and human wastes.
As the mud disperses, it releases more nutrients, while clouding the water.
Dense plankton blooms follow, clouding the water further. Dead plankton
organisms sink down as detritus, and they are recycled by bacteria breaking
them down to nutrients again. This requires much oxygen. The darkness of
the water prevents the phytoplankton from producing the required oxygen.
As the situation worsens, more and more oxygen is used up until all organisms
die, and a dead-zone is formed. As human populations increase and the land
degrades, requiring more and more fertiliser, dead-zones will become more
commonplace. At he mouth of the Mississippi River (west of it) now every
year large dead zones form of 22,000 km2. these areas are totally devoid
of fish and other life except for anoxic bacteria. Farming using excessive
nitrogen fertilisers in the river's catchment area is blamed for this and
a plan has been formulated to reduce dead zones by 30% by the year 2015.
Now that we have
established that serious threats exist to our seas, let's look at the conservation
tools available. They aim to make the resource last, hopefully forever.
Most regulations are enshrined in law so that they apply to everyone, ensuring
that all stakeholders are treated (disadvantaged) equally.
methods: regulating and designing methods
aimed at causing less harm to the fish caught, those that escape, while
also causing less collateral damage to non-target species like sea birds.
By regulating mesh sizes, it is hoped that small fish can escape in order
to take part in reproduction before being caught. Every method of fishing
has its specific problems and regulations, discussed in the planned chapter
sizes: it is believed that a fishery can be
improved by size restrictions. Traditionally, the small fish are returned
to the sea, and only the big ones are taken. The small fish will then be
able to partake in spawning before being eligible to be caught. However,
large fish have large spawning masses and are effective spawners. They
have learnt how to do it and produce a disproportionately large amount
of fertilised eggs. The small fish produce a large spawning mass, but relatively
few fertilised eggs. So perhaps we should leave the big ones and take the
seasons: by closing the fishery during certain
seasons, fish can be allowed to spawn in peace. In other cases, shellfish
in poor state can be prevented from appearing on the markets. Trawled habitats
are allowed to recover.
areas: by closing certain areas, it is hoped
that fish can recover. Such areas can be reopened at a later date. A marine
reserve is in fact a permanently closed area. Certain areas can be allocated
to certain stakeholders, to foster responsibility over their management.
quotas: conditions can be set for joining
the fishery, to prevent a wholesale bonanza. By allocating quotas for each
species, the fishery can be limited, while at the same time giving fishermen
the freedom to decide where and when to fish.
marine reserves: permanently closed areas
of the sea are thought to give numerous advantages, discussed further in
this chapter. The word Marine Protected Area (MPA) is identical to marine
reserve, but often meaning that some form of extraction is allowed.
habitat restoration: for completeness, this
point is mentioned here, although it is not a practical solution for the
sea. However, artificial reefs have been created experimentally in many
places, and ships are dumped for their value as underwater wrecks, expecting
that they will be covered with sea life, while attracting fish schools
as well. Where sea walls and groynes are placed, an artificial rocky shore
is created. Any hard structure surrounded by a sandy bottom, will act as
an oasis for reef organisms.
captive breeding: captive breeding of sea
creatures is tempting because very large numbers can be raised, as opposed
to threatened mammals or reptiles. The juveniles can be reared to a size
sufficiently large to find their food outside the plankton, where they
would fall prey easily. However, in practice, no successes have been recorded
from re-releases into the wild.
education: a large part of our use of the
sea is not regulated well. It concerns the amateur fishermen who take small
amounts for private use, but because of their numbers, they can have a
profound depeletionary effect. Education aims to foster responsibility
by understanding the consequences of one's actions. This could lead to
As one can see, our conservation tools are not able
to stop mud and nutrients from flowing into the sea, which has become our
main problem along our coasts. In the remainder of this chapter, we'll
concentrate on marine reserves and their benefits and limitations. Fishery
and its implications will be treated in a separate chapter. Perhaps it
is the right place here to make an important distinction between conservation
and management. Fishermen talk about management, and conservationists about
conservation. What do they mean?
Management = the threats remain, but
managed at a magnitude to cause no permanent harm.
Conservation = taking all (human-caused) threats
like terrestrial wildlife reserves, can come in a variety of forms, depending
on the amount of extraction allowed. In this respect it pays to review
the following possible scenarios, arranged in order of the amount of extraction
a free commons: without any restrictions,
people can take what they want and where. If you don't take it, someone
else will. This leads to pillage and plunder for individual benefit. Read
about the tragedy of the commons.
regulation: by regulating the extraction process,
with the management/conservation tools outlined above, the rate of extraction
can be controlled to keep up with natural replenishment. It can still lead
to a collapse of the stock. By focusing on a single species, the environment
becomes unbalanced, the consequences of which are poorly understood.
balanced extraction: instead of regulating
a single species, whole habitat zones or areas are regulated and fished
to maintain a balance in numbers of each species. However, the old animals
still disappear, which creates another kind of imbalance.
protect but take some: an area is protected
but a limited amount of extraction is allowed. This amount is kept well
below the commercial targets involved in the kind of management above.
In this manner the fish stock is not threatened, and imbalances in populations
are not critical.
no-take protection: this is the present marine
reserves concept. Within the protected area, no form of extraction is allowed.
Any use causing damage to organisms is outlawed too. It is a cost-effective
way to allow areas to recover. However, design shortcomings can render
marine reserves ineffective, and neither do they protect against the main
scourge, runoff from the land.
pristine wilderness: a concerted effort is
made to create pristine wilderness areas, free from all problems and large
enough to work, forever. It involves restoration of the land in the catchment
area and around. A certain degree of education may be required before access
is granted to visitors.
Which of the above scenarios will deliver the most
benefit is not easy to say. Extraction gives measurable benefits to people,
but is usually detrimental to the environment. However, all natural populations
benefit from a limited amount of extraction, although some areas are too
sensitive to sustain exploitation. Thus complete protection may not deliver
the largest net benefit, but it has merits of its own. It must also be
remembered that by relieving the pressure on one area, one therefore increases
the pressure on other areas.
The terminology for
marine reserves is rather confusing and differs in different countries.
The Americans use the following terms:
Protected Area: recognises the uniqueness of a habitat, and protects
biodiversity while allowing other uses (multiple uses) such as camping,
tramping and even hunting.
Marine Protected Area: the same, but no restrictions on use. (food,
Marine Reserves or Biological Preserves: very restricted on their
use (no take)
Australia has different names for zones of varying intensities of
protection and restricted activities
general use zone:
habitat protection zone:
conservation park zone:
national park zone:
New Zealand also has a number of protected marine
marine park: a no-take marine reserve created and managed outside
the Marine Reserves Act, by local counties or the Minister of Fisheries
under the Fisheries Act 1996.
marine reserve: a no-take marine reserve, managed by the Department
of Conservation under the Marine reserves Act.
taiapure reserve: an area set aside to be managed by the
local Maori for traditional fishing. This usually but not exclusively,
involves fishing for official gatherings (hui), which in the Maori
tradition, serve meals with seafood (kai moana). The white man (pakeha)
have, in theory, similar access to the fish resource, but require consent
from the local (Maori) management committee (tikanga). The
committee may decide whether commercial fishing is allowed, and how. The
area is managed under the Fisheries Act.
mataitai reserve: an area of considerable traditional importance
to Maori (tangata whenua). The fishing resource is managed locally
for amateur catches only (by both Maori and non-Maori), but on a sustainable
basis. Commercial catches are excluded. This type of reserve is enforced
by the Fisheries Act.
Perceived benefits of protection
In New Zealand marine conservation started from the
need of marine scientists to do undisturbed measurements in the sea. They
needed a place where their experiments would not be eaten. But gradually
the concept grew, and other benefits were perceived. Eventually a long
and exhaustive list of benefits became the conservationist's argument for
having more marine reserves. But first the simple list of expectations:
scientific research: an area where untoward influences and disturbances
such as extraction, are kept out. this has proved to be quite beneficial
for studying commercial species. However, the thousands of non-commercial
(non-fished) species, can be studied equally well outside a marine reserve.
Furthermore, many marine reserves do not represent the habitats frequented
by commercial fish species, so they are of little relevance to scientific
research about them.
baseline: the area would eventually stabilise at near-constant and
maximum stocking levels, with a balance between populations. Other areas
can be compared with this 'baseline'. An area excluded from exploitation,
also enables scientists to study the (side-) effect of exploitation, by
comparing the situation inside the reserve with that of locations outside.
However, reserves need to be large in order to achieve this benefit. Also
all threats need to be excluded, which includes runoff from the land. In
practice, many reserves are degrading because of this. 'Baselines' are
useless if they are not monitored and quantified, which is often omitted
for lack of funds.
hatchery: the creatures inside the reserve will grow old and reproduce
profusely, it is thought. Their offspring will spread to areas outside
the reserve. Because the reserve is fully stocked, fish will spill over
to adjacent areas where they can be caught. However, the reserve area is
very small compared with the area outside, and their stocking levels are
no more than 3 times better.
insurance policy: fisheries management has shown to be flawed, for
reasons insufficiently known. Marine reserves could then act as an insurance
against human mistakes. However, the fishing outside has a negative influence
on stock levels inside a reserve, unless reserves are larger than a few
hundred square kilometres.
easy strategy: the no-take strategy is very easy to implement, police
and to manage. No prior knowledge is needed; no sophisticated management
techniques either. However, marine reserves can easily be hampered by poor
design. When very successful, they need to be policed constantly, because
poaching pays well.
enjoyment: while serving its purpose, the marine reserve can still
be enjoyed by others for fish watching, snorkelling, SCUBA diving and underwater
photography. By separating the takers from the lookers, an area is created
where fish can be enjoyed time and again. However, the sheer presence of
thousands of visitors leaves a mark on fish behaviour and sometimes on
the environment as well.
education: because the marine reserve is more natural and has more
to offer, schools will use it for education. Universities will use it to
train students and for qualification studies. It will put pressure on those
reserves which are easiest to access.
The simple list of benefits above has expanded
over time, with the addition of more and more detail. Just hang in there
and read this list carefully, because it contains some fallacies, myths
fishery: benefits of interest to fisheries
management and fishermen.
protect spawning fish stocks: reserves can be placed over spawning
grounds, thereby effectively protecting fish during the entire mating season.
However, we should know such places exactly and they should not move around
in time as fish choose to spawn somewhere else. Each fish species has a
different way of replicating, most species not sharing the same spawning
grounds. Marine reserves allow fish to grow old, thereby becoming effective
spawners but they need to go outside to spawn.
increase spawning stock biomass: fish numbers and size increase
within a reserve, thus their compound biomass too. However, the most important
contributors to fertilised eggs are the old and experienced fish. Reserves
need to be large to accommodate these. Most of our commercial fish species
move around freely, and are not confined to marine reserves.
increase spawning density: an increased number of fish taking part
in spawning, could increase the spawning density, leading to more fertilised
eggs. However, little is known or measured about this.
provides greater population fecundity/ reproductive capacity: is
the same as mentioned above.
provides undisturbed spawning conditions/habitats/sites: same as
allow producing more egges/larvae: same as above.
provides export of eggs/larvae: same as above.
enhances recruitment: if more fertile eggs are produced, then more
larvae and a higher recruitment may result. However, recruitment is dependent
on a large number of factors, and varies enormously, whether the larvae
come from marine reserves or not. Nearly all larvae spend a considerable
time (days to weeks) in the plankton, during which time they are subject
to considerable predation.
provides spillover of adults: It is claimed that a marine reserve
improves fishing outside because of spillover. However, repeated measurements
on tropical marine reserves have shown that this amounts to less than 35%
of the lost fishery. What happens to small reserves, is that the spawning
stock spills out, which is not what was intended.
provides spillover of juveniles: It is claimed that marine reserves
attract more juveniles to recruit there. However, recruits do not know
the difference and settle by chance equally inside as outside. Because
the reserve is thought to be fully stocked, the juveniles recruited there
find no room, and have to spill out. However, recruits are less likely
to survive inside a marine reserve, because there are more and larger predators
juveniles settle and adults migrate out: initially the abundance
inside a marine reserve is caused by juveniles settling and growing to
adults. It is claimed that this process continues and that adults migrate
out. See the two points above.
fishing improves near the reserve: as adults spill out, fishing
is indeed better near the reserve's boundary. However, this amounts to
less than half of the lost fishery. Furthermore, because people fish the
reserve's boundary intensively, the stocks there are very depleted, which
invites more fish to migrate out of the reserve, thus depleting the stock
up to 2-3km inside. It can render a small reserve ineffective.
reduces chances of recruitment overfishing: because fishing is disallowed
inside the reserve, the recruits there cannot be fished accidentally as
by-catch. However, if this is a problem, it should be fixed by fishing
in a less damaging way, for the numbers of recruits fished accidentally
outside the reserve, is many times higher. The numbers exempted by the
reserve are negligible compared to the whole. Furthermore, all fishing
methods aim to exclude juveniles, thus for the young fish, the presence
or absence of marine reserves does not matter. For old fish it does.
reduces overfishing of vulnerable species: same as above.
genetic diversity increases within the large, old members of the population:
marine reserves are very beneficial to old fish which stay inside. After
a long period, more of these are expected, thereby increasing their biodiversity.
However, their numbers remain very small compared to the numerous young
fish inside and outside. An old fish does not have more genes than a young
one. Thus biodiversity is mainly made up of young individuals, on which
the reserve has very little influence.
protects diversity of fishing opportunities: ?nonsense?
reduces adverse impacts on fish genetics: same as above
improves ability to recover from management
failure: the reserve is not managed by fisheries, and is therefore
insensitive to mistakes made this way. It acts like an insurance. Should
fish have been wiped out outside the reserve, the reserve can provide new
larvae and recruits to colonise the outside. However, reserves should be
very large if they are to play such a role, and if they are not to be affected
by disasters outside. Most disasters, natural or man-made, affect reserves
just as much.
reduces inadvertent fishing mortalities: same as above.
reduces by-catch in the region: same as above. However, by exempting
a certain area, one also increases fishing pressure on the other areas,
resulting in the same by-catch of the combined area.
simplifies enforcement & compliance: marine reserves fall outside
fisheries enforcement, but need their own enforcement and compliance. The
whole becomes more complicated, because fishermen have to be kept out of
certain areas, which was not the case before a reserve was established.
Poachers have to be caught and punished using different laws.
helps reduce conflicts between users: it only helps to reduce the
conflict between those who wish to observe, and those who wish to take,
and it does this well. It does nothing to reduce conflict between trawlers
and longliners for example.
maintains sport trophy fisheries: because fish grow larger inside
a reserve, they may become good fishing trophies after dozens of years.
However, a reserve which leaks old fish out, is not a good one. The number
of trophy fish produced by a reserve is very low. One would not like trophy
fish to leak out.
provides better management with less data: the idea is that marine
reserves can make good anything that goes wrong outside. The extreme of
this is to have the main part of the sea as reserve (say 70%), and a smaller
part outside for fishing (say 30%). Then no management would be required
at all. However, this is not an optimally productive situation. Besides,
reserves do not work well for migrating stocks, which comprise by far the
largest part of commercial fisheries.
facilitates user involvement in management:
?nonsense? the idea is perhaps that not just a clique of commercial fishermen
have their say. Who are the users?
provides baseline informatin for stock assessment & fisheries control:
in present-day fisheries, the assessment of today's stock is crucial to
the decision as to how much to catch next year. But stock assessment is
difficult and prone to large errors, and the knowledge is often delayed
by several years. Since fishing has gone on for centuries before any management
began, the sizes of the original (pristine) stocks are not known. Is today's
stock 5% or 60% of what once was? In reserves that are large enough, stocks
may be able to recover to their pristine levels, which would be of great
benefit to fisheries management of the areas outside. However, fish stocks
are rather 'patchy' while also moving around. Thus marine reserves need
to be very large in order to gain this benefit, and they should also be
located amongst the traditional fishing grounds. To establish fishing densities
inside marine reserves using traditional scientific trawls, is often not
acceptable. Thus we may never know whether a 'baseline' is reached.
stock reaches unexploited levels: it is hoped that the density of
the fish stocks inside a marine reserve will level out as that for pristine
stocks. We may be able to see what the sea looked like before the advent
of fishing. However, marine reserves are still coupled to the outside,
and influenced by what happens there. Some of the detrimental environmental
changes have been global (exhaust gases, water cycle) or too large to control
to our knowledge base or to scientific research.
controls: a reserve can be used for long-term monitoring, without
human interference. The data obtained this way, can give insight in the
more natural state of the environment, like that of interactions between
balanced communities. The situation inside can be compared with that outside,
and the effects or consequences of our actions better assessed. However,
long term monitoring must also be done outside, which will be the main
effort due to its sheer size. Reserves are of course of limited importance
to migrating stocks.
natural baselines & processes: same as above.
protection of work, focus for studies: same as above. Because experiments
are not interfered with, they are preferably done inside a reserve. However,
by far most marine species (say 99%) are not caught commercially, and are
therefore not interfered with. Besides, natural events such as large storms,
wreak the same havoc inside a reserve as they do outside.
continuity of knowledge in undisturbed sites: ?nonsense?
restores natural behaviour: see above.
educational benefits for marine studies and other.
schools: where marine studies are part of the school curriculum,
schools will find a visit to a reserve of benefit because there is more
to see. The rocky shore for instance, is not harvested. However, the increased
damage of many feet, the overturning of boulders and general habitat disturbance,
become very noticeable half-way through the season. It kills the longer
living organisms, and changes the habitats.
general public: the general public is allowed access, and many start
to explore the water with masks and fins. However, the sheer numbers of
people do leave their mark, particularly when the environment is sensitive
(coral reefs for instance).
general awareness: a marine reserve draws attention and raises initial
interest, which can be followed up by education. Initially, most visitors
are entirely ignorant of what lives in the sea and how it lives there.
They think that fish are stupid, cold-blooded animals and good only for
food. After a visit, they become interested in feeding the fishes and giving
them a good chase. But gradually they become fascinated by other aspects.
They read a brochure, or the information displayed in a kiosk. They warm
up to the concept of marine conservation. Without general awareness, such
a process would probably not happen.
indirect awareness: people can become interested in the sea by watching
slides, videos, drawings, and by reading articles. Many are too frail to
swim in the sea, but a glass-bottom boat could give them a hands-on experience.
However, there exists a relentless competition for people's indirect awareness
by a million of other things. The sea comes in at low priority, because
we don't live there. Then again, a marine reserve would enable photographers
and writers to obtain the resource material to promote indirect awareness.
water sports: it is obvious that a marine reserve attracts SCUBA
divers and their trainers. Snorkelling is favourite because of its simplicity
and low cost. Marine reserves are also used for swimming, sun bathing,
surfing, boogie-boarding, kayaking and outdoor education. With a bit of
luck this too may spark awareness.
a collection of other benefits.
recreation: separates takers from watchers. This is what a marine
reserve does with excellence. It creates areas where people are sure that
the fish will be there next time.
health: the idea is that reserves could act like marine green belts,
like parks do on land. However, the green bits (plankton and seaweed) in
the sea are not exploited, and a marine reserve does not have more of it
spiritual: it is indeed an awesome experience to have your boat
anchored in a place of beauty; finding yourself surrounded by deep blue
water and the cries of birds; seething waters, stirred by schools of surface-feeding
fish; observing an incredibly diverse marine environment, studded with
colourful fish who do not seem to fear; at night a cacophony of cries of
homing seabirds and blue penguins squawking while drying their feathers.
How do we set aside such places for our children and theirs in perpetuity?
It is worth a lot to me.
monitoring: see above.
human effects outside: see above.
planning: by observing how reserves work (or don't work), how they
are used, how life returns or fades, how communities interact, how natural
cycles progress, valuable insight can be gained for designing future reserves
and for managing these. However, very little is done in this area.
benefits for the management of our resources. These are the same as the
benefits for fishing and fishery management, discussed above.
easier measurement of management effects: by providing controls.
rapid effects of technology/ market forces on extraction: the effect
of technology on the efficiency of fishing is very difficult to assess.
Since fishing models use catch-per-unit-effort (CPUE), often taking a fishing
day at sea as Unit Effort, they can make large errors when the technology
allows a fisherman to catch ten times more each day than he used to. Was
the increased catch due to technological improvement, or because there
is more fish? Therefore CPUE is poorly related to stock levels, causing
stock assessments to err on the high (wrong) side. Marine reserves do not
provide help here either because it would be madness to have them fished
for reference. The best way to assess stocks, is to do standard test trawls,
ignoring new technology.
lack of enforcement: see above.
reducing the effects of incidental damage: see above.
benefits to the marine ecosystem.
ecosystem functioning and integrity: in case a marine reserve returns
to a more natural state, with balanced communities, it will also function
more naturally, and therefore more optimally too. Sea urchins are found
grazing seaweeds and this provides food for their predators like snapper
and crayfish. Sea otters rebound in a similar fashion, feeding on sea urchins
that feed on the macrocystis seaweed in the USA.
ecosystem services: the world's ecosystems provide many services
to mankind, like regulating the temperature of the planet, recycling our
wastes (sewage, water, CO2) and so on. The idea is that marine reserves
in their more natural state, help. However, by far the majority of ecosystem
services are provided by lower organisms like bacteria and plankton. These
work equally well inside as they do outside marine reserves.
high density effects: some species need densities for their survival.
Some need it when mating or spawning, to get excited and to achieve better
success. Scallops need to be close together for their male and female gametes
to meet. Marine reserves could provide such densities, but only for those
hunted outside (scallop, mussel, some fish). They must be placed where
such organisms like to live. A rocky shore reserve cannot be expected to
protect a scallop bed.
physical structure of habitat: when a scallop bed gets trawled,
the sea soil is more or less ploughed, which changes its structure and
may prevent larvae from settling, or cause likewise effects (little is
known!). A marine reserve suffers no such damage, and can develop the proper
physical structures needed by its organisms. True. However, many shellfish
beds have shown to thrive under moderate extraction, becoming more productive
than without it.
composition, presence & abundance of species:
biodiversity at all levels: as food species become more numerous,
so do the ones dependent on them, at all levels from the deep to the shallows,
and from simple to complex organisms. However, since most species are not
hunted (except in the tropics), little effect can be expected.
keystone species: the species on which others depend, such as for
food, cleaning. They must occur in large numbers to be of importance. Marine
reserves are indeed beneficial to these.
vulnerable species: those which are easily disturbed or damaged
threshold effects: if a species is all but fished out, its function
may be taken by some other species, causing the ecosystem to 'flip', possibly
so that the hunted species is no longer able to re-establish itself. It
is thought that the presence of a small 'normal' situation among a vast
'abnormal' extent, is able to drive the 'abnormal' situation out and back
to normality. However, this is not in accordance with ecological laws.
second order effects: as above.
trophic structure: fisheries collapses cause fishermen to fish for
less desirable, often smaller fish. Eventually they fish for those species
that once were food (prey) for the large fish. These smaller fish occupy
a lower trophic (food) level. Fishing thus lowers the average trophic level
of the fish stock. A marine reserve may be able to revert this. However,
the main recruitment into a marine reserve still comes from outside, thus
at the lower trophic average established there. Relatively more prey fish
will recruit than predators.
system resilience: biodiversity, overcapacity
and replication are nature's weapons for resilience against adversity (see
management/resilience). As discussed above, these factors are stronger
inside than outside, but perhaps not more than twice as much. Main events
happening outside, will influence the marine reserve like falling domino
stones do, because the two are still strongly coupled. Clever marine reserve
design will attempt to minimise such couplings.
high quality feeding areas: because there is more fish and variety,
predator fish, birds and sea mammals can find their food more easily. Even
with small shifts in population densities, this may amount to a large shift
in availability of food for them (see resource
management/economies of exploitation). However, a marine reserve needs
to be large to achieve this. In order to sustain a pod of dolphins, a reserve
may well need to exceed 200km2 in area. The Kermadecs Marine Reserve of
over 7000km2 supports but one pod of dolphins. It would be easier to achieve
commercial fishing at higher stocking levels. This would make commercial
fishing easier as well, while making marine reserves less needed.
benefits to our efforts of conserving the living world.
genetic: see above.
species: see above.
habitat: see above.
ecosystem: see above.
ethical/spiritual: benefits to our values and
beliefs, which are impossible to measure. See above.
intergenerational rights: saving for our children. This is perhaps
one of the most important qualities of marine reserves.
social: a place to meet and do things, swimming, boating, snorkelling,
SCUBA. However, such activities have an influence on the environment. Swimming
and boating are not dependent on the presence of a marine reserve.
aesthetic: enjoyment of existence. A natural, pristine place with
heritage: preserving past significance.
economic: economic benefits.
efficacy/efficiency: because reserves do not cost much to establish,
and because of their large perceived benefits, they may well be solutions
providing 'most bangs for the bucks', or most result for least cost. However,
no scientific proof exists, and the sheer amount of management and policing
a large number of small reserves, may become unaffordable. Reserves, when
properly used, do need a lot of money, see box below.
employment: it creates sustainable jobs in interpretation, management,
policing, monitoring, science, education. However, for most of these a
yearly budget of public money is needed, which is often overlooked when
establishing a marine reserve. It is a hidden cost. When they are not managed
locally, many of the proclaimed jobs and contracts, go to people living
elsewhere, and the local area does not benefit.
Reserves Called Best Hope for Ocean Species
Population densities were on
average 91 percent higher than those outside reserves. Biomass was 192
percent higher; average organism size was 31 percent higher; species diversity
was 23 percent higher. http://www.ens-news.com/ens/feb2001/2001L-02-22-06.html.
& Fallacies (5).
get their act together
In 1991 the Potter Commission
(commissioned by NOAA) suggested $30M/year as adequate funding. Actual
amount was $4M. In 2000 actual funding became $26M/yr. A sanctuary must
have: own boat, manager, outreach + science coordinator, interpretation
centre, facilities. Congress decided that no new sanctuaries should be
created until the existing ones establish active programs of education,
research, monitoring and onshore facilities from the limited budget. But
should sanctuaries be held up for lack of funding? The recource may be
lost by waiting.
As one can see, the
perceived benefits of marine reserves may not substantiate at all, either
because such benefits have been constructed in our minds, lacking a sense
of reality, or they may not eventuate due to poor reserve design, such
as making the areas too small, or with their boundaries in the wrong place.
This will be discussed in a further chapter. One should be skeptical about
claims like those discussed above, also because some benefits will be achieved
only in some situations. Coral reefs, for example, are fished in their
entirety: reef fish for food, clams for food, shells and starfish for collectors,
corals for aquariums, small reef fish for aquariums, seahorses for doubtful
medicines, turtles and much more. It is understandable then that closure
of an area then leads to spectacular recovery. However, in temperate seas
where such elaborate extraction is unusual, and commercial fish species
are mainly migratory, bottom dwelling or pelagic, the closure of an area
gives a much less spectacular recovery or benefit.
It is furthermore helpful to remember that marine
reserves do not protect against the following threats:
disasters: these can be natural or human-induced.
storms: large storms do not occur frequently,
but they can cause severe damage, from which an area recovers only slowly.
Such damage may be much larger than humans could cause. However, usually
ecosystems have evolved so that they can recover their functionality readily.
rain storms: when hurricanes die out, they
release a vast quantity of very heavy rain. In 1983, cyclone Bola rained
out over New Zealand, causing massive erosion to the land and dense clouds
of silt in the sea. Inside the Goat Island marine reserve it deposited
a layer of 10cm thick clay, destroying deep shellfish beds (Atrina)
and more. It took over 7 years for this damage to be cleaned up by successive
oil spills: marine reserves are just as likely
to suffer oil spills as the areas outside. If marine life is more prolific
inside, then oil slicks do more damage to marine reserves than they do
poisonous plankton blooms: these have become
more frequent and severe in recent years, able to kill a large variety
of species and in large numbers. Marine reserves are in no way exempt to
gradual degradation: all along the coasts
of all continents, the seas are degrading due to human activity and habitation.
Marine reserves are not protected against this, neither do they have more
resilience. The main indicator is the water's visibility or clarity. Coastal
water should do better than 10m, but it has degraded to 5m and less over
natural fluctuations: natural fluctuations
are part of any ecosystem, although healthy ecosystems have less of these
and not so severe. Many fluctuations are caused by temperature changes
and world-wide climate events like El Niño.
ecosystem shifts: ecosystem shifts can happen
because of extracting single species. The stress caused by the outside,
is often too large to be negated by a marine reserve. Invasive introduced
species can also cause ecosystem shifts. The marine reserve is too much
a part of the outside to be exempted.
caused by human habitation and industry. Marine reserves do not protect
against pollution reaching the sea.
erosion sediments: the natural forests have
been changed into agricultural land everywhere in the world, and at an
increasing rate, complete with ploughing the soil. Because of this and
other earth works, the amount of sediment reaching the sea is over ten
times what was naturally. It suffocates water-breathing creatures, reduces
visibility, kills plants, fertilises the sea, and has a profound adverse
effect on the marine environment. Marine reserves are neither exempt, nor
sewage: particularly where humans congregate
in their cities, the outflows of sewage are more than the environment can
handle, although this is not immediately evident. The marine environment
degrades, but only when the seas become nasty and poisonous, becomes the
link between sewage and degradation visible for all. However, then it is
too late to fix it. Sewage (treated or not) contains a very potent mix
of fertilisers, to which plankton reacts instantaneously. Society must
do more towards sewage recycling, or depositing it very far out in the
ocean, beyond the continental shelf.
industrial chemicals: many industrial chemicals
are poisonous and/or degrade slowly in the environment.
agricultural chemicals: these are used over
vast tracts of land, and in large doses. So their quantities are to be
reckoned with. Most of these chemicals aim at extinguishing life (biocides),
ranging from fungi and bacteria to higher forms (worms, insects). Related
life forms are also found in the sea, and they are similarly affected by
fertilisers: in Man's efforts to gain the
most from the least land, he uses fertilisers past the amount, safe to
prevent leaching from the soil. The fertility locked up in the sediment
from erosion, also fertilises the sea, resulting in reduced visibility
and poisonous plankton blooms.
anti-fouling: a special class of biocides
is aimed at combating the colonisation of ship's hulls by marine organisms.
They too are long-lasting, have a widely ranging biocidal spectrum and
are effective in small doses. Such persistent biocides are released slowly
by the paints on these hulls, affecting the environment where many ships
are berthed. They can also be accumulated inside marine life.
nuclear: radioactivity has long-term components,
which may spread through the entire ocean. A radioactive dump in the Atlantic
may affect marine life in Hawaii. However, such threat has not yet eventuated,
and it can be prevented at source.
introduced species: some accidentally introduced
marine species have become invasive, causing measurable effects on the
marine environment or even ecosystem shifts. Marine reserves are not excepted.
gene pool too small: if marine reserves were
to exist on their own, their combined gene pool (of extracted species)
would be much smaller than that of a properly managed fishery.
disease: introduced diseases or other diseases
would spread well inside a marine reserve due to its higher densities.
old individuals: the way we fish is particularly
disastrous for old and large fish, simply because during their lifetime
they are exposed more frequently to the chance of being caught, and once
caught, the natural investment of many years is lost instantaneously. Many
old fish form lasting male-female pairbonds, which enhances their spawning
success considerably. By catching one, the pairbond is destroyed and may
not ever be repaired. Old fish need large territories and they habitually
swim large distances for feeding and spawning. Marine reserves appear to
be inadequate, also because a small reserve can have only few 'awesome'
marine reserves cannot protect against global changes or against their
effects on the environment.
global warming: won't prevent global warming
or rising seas, and the warmer (or colder) seas will affect marine reserves
as much as they do the rest of the sea.
increased CO2, NOx and SO2 emissions: emissions
from burning fossil fuel, contain fertiliser components that fertilise
the sea (and the land, and then the sea), causing the plankton to bloom
more intensively. These reach marine reserves as much as they reach the
increased ultraviolet radiation: ultraviolet
light, unlike infrared light, penetrates the sea for several metres. In
this zone it could cause death and mutations. Marine plankton organisms
do not have ultraviolet-fending opaque skins, but are completely transparent,
thus sensitive to exposure of this kind. However, the threat of UV radiation
has existed for many millions of years.
marine reserves can help fisheries as outlined above, but not for:
fisheries collapses: marine reserves cannot
stop fisheries from collapsing outside. But they may be able to help them
recover more quickly. However, due to the variability in spawning success
(one fish being capable of producing a million offspring), a reserve's
beneficial influence may be negligible or unmeasurable.
migratory species: fish that move around,
do not benefit from marine reserves. Migratory fish such as salmon and
tuna are good examples. But most of our commercial fish species are not
locked in to a specific area either. They are so numerous because their
habitat is large and contiguous (the vast sea bottom, or the open ocean),
and this invites them to move around like migratory fish do.
bycatches: obviously, marine reserves do not
protect against these.
wrong habitat: no marine reserve can help
managing any fishery. Its main habitat must correspond to that of the fishery.
For instance, a rocky shore marine reserve has no value for flounder fishery
or deepwater or pelagic fishery.
most of all marine research is not done inside marine reserves, but inside
laboratories and outside marine reserves, for the simple reason that the
number of exploited species is very small compared to the rest of marine
organisms. But there are areas of interest which can be investigated only
inside the protection of a marine reserve.
monitoring: certainly all marine reserves
should be monitored, but this does not lessen the need for monitoring the
outside, a much bigger job. For assessing oil slick damage and insurance
claims, such monitoring would pay for itself in the long run. As it stands,
however, too little is done.
From the above, it becomes evident, that the
best ways to conserve the marine environment, is for fisheries to get their
act together, and for us all to reduce sediment and sewage flows into the
sea. To fish in an environmentally friendly way does not cost more or yield
less than what we are doing now. Fixing sediment and sewage, however, is
a very much more difficult matter.
If we agree that conservation means taking all threats away permanently,
then marine reserves have only little influence on the quality of the environment
where other threats remain.
Having learnt what marine reserves can't do, what is it that marine
reserves do particularly well?
protect age composition: the fate of slow growing fish is that they
usually get caught before maturity. Often these fish are born female, only
to change into males at a later age (protogynous). Where fishing
is intensive, such males become rare. Fully protected marine reserves have
shown to produce not only more fish, but over time, also older fish. For
some species this means a decisive difference in the amount of spawn produced.
But reserves must be large to achieve sustainable populations that do not
protect a unique spot: some places in the sea are hot spots of biodiversity,
a treasure to enjoy. Many of these are unique and irreplaceable. A marine
reserve is able to protect such treasures for future generations, provided
that there are no other threats, like pollution. Remote islands and sea
mounts, which do not suffer from pollution, are such places where reserves
will work. They furthermore support sensitive environments in need of protection.
protect scientific experiments: many scientific experiments require
simple structures on rocks, attached to buoys, and so on, protected from
people with vandalistic instincts. Fish and other organisms are laboriously
tagged and observed. The marine reserve protects them from being eaten,
but not from their natural predators.
separate the takers from the lookers: it is amazing how much damage
one taker can do, hence marine reserves which allow some extraction, are
not worth having for the people who come for looking.
attract people when access is easy: the idea of visiting a paradise
with friendly fishes, is catching on, even though only 20 years ago, this
was unheard of. Consequently, people wishing to do so, already outnumber
those who wish to fish. Many fishermen are doing both. For a marine reserve
to be of benefit, it has to be easily accessible.
help marine education: where else would you like to take your child
or the school class to become acquainted with the sea? Let their first
experience also be their best! Perhaps the most important quality of reserves
is that they have been set aside for our children.
help underwater photography: where spearfishermen have worked, the
fish have become very shy of people in the water. It takes a long time
before they collectively trust humans again. Inside an established marine
reserve, fish indeed gradually lose their fear, but due to ignorant human
behaviour, some are frightened away.
Marine conservation did not happen overnight. It
is a reactionary process, in which we react to problems as they occur,
finding solutions as they are needed. But perhaps we need to think it through
logically, from the ground up. What is expected of a protected area, is
the subject of next chapter.
Objectives of marine conservation
Rather than imagining what reserves could do, this chapter deals with what
the policies are behind marine conservation and how these developed. The
objectives as expressed by various countries follows here.
National Wildlife Refuge System (NWRFS): predominantly terrestrially
preserve, restore and enhance
in their natural ecosystems (when practicable) all species of animals and
plants that are endangered or threatened with becoming endangered.
perpetuate migratory bird resources.
preserve biological diversity.
provide the public with an understanding
and appreciation of fish and wildlife ecology and the human role in the
However: it does not look at
biological diversity overall, but only at endangered species and commercially
or recreationally important species.
National Marine Sanctuaries Program (NMS, 1972)
to identify areas of the marine
environment of special national significance due to their resource or human-use
to provide authority for comprehensive
and coordinated conservation and management of these marine areas that
will complement existing regulatory authorities.
to support, promote and coordinate
scientific research on, and monitoring of the resource of these marine
to enhance public awareness,
understanding, appreciation, and wise use of the marine environment.
to facilitate, to the extent
compatible with the primary objective of resource protection, all public
and private uses of the resources of these marine areas not prohibited
pursuant to other authorities.
Close observers mention that
it suffers from the following problems: indadequate funding; no management;
no research; no education efforts. It is interested only in values with
respect to resource use and human use. It does not mention biodiversity,
or a no-take policy. It is poorly defined in terms of conservational values.
WASHINGTON, DC, August 27,
2001 (ENS) - America's large system of nature preserves fails to encompass
the full range of the nation's biodiversity, a new report shows. The study
by U.S. Geological Survey biologists shows that the United States has selectively
protected lands that lack commercial, agricultural or other human values,
leaving entire ecosystems unrepresented. http://ens-news.com/ens/aug2001/2001L-08-27-07.html
Canada wishes to have a
system of marine protected areas in place by the year 2010. It wishes
to go along the following lines:
working with people & communities
respecting the treaty process
ecosystem based management
learning by doing, flexibility
managing for sustainability
It has established a working
group to guide the process, with a mandate to:
provide policy, advice, interpretation
oversee public communications
manage a joint central system
for tracking and monitoring the MPA.
ensure a consistent approach
The working group identifies,
assesses and recommends priorities regarding:
key marine areas identified
by government agencies, First Nations, marine stakeholders, community groups,
academic institution, individuals
assessment according to MPA
recommendation based on consistency
with the objective of MPA strategy, & complementary to other marine
uses & activities, as already planned regionally
decision making: recommendation
reviewed by government. Additional studies may be needed. Management authority
management plan: the agency
supporting the MPA is responsible for making a management plan: purpose,
goals, objectives, how to be reached, permissible uses, where, what, when.
Management plans are subject to periodic review.
Management Act New Zealand (1993): Managing the use, development and
protection of natural and physical resources in a way, or at a rate, which
enables people and communities to provide for their social, economic, and
cultural wellbeing and for their health and safety, while:
sustaining the potential of
natural and physical resources (excluding minerals) to meet the reasonably
foreseeable needs for future generations;
safeguarding the life-supporting
capacity of air, water, soil, and ecosystems
avoiding, remedying, or mitigating
any adverse effects of activities on the environment;
maintaining or enhancing the
quality of the environment;
exploiting at ecologically sustainable
protecting Maori taonga.
Zealand Biodiversity Strategy, March 2000.
maintain and restore a full
range of New Zealand's habitats and ecosystems
maintain the genetic resources
of our important introduced species, which provide much of the foundation
for our economy.
enhance community guardianship
of our indigenous species and where they live, and promote co-ordinated
community action to bring species extinction to a halt
Zealand's Marine Reserves Act 1971: the purpose of marine reserves
for conducting marine research
total protection of all species
Additions and amendments have
been proposed to the act, for it to protect biodiversity, to apply to the
entire EEZ (370km rather than 23); to be more specific about its application
and consultation process; to allow for a wider range of purposes rather
than just for scientific research; to include references to the Treaty
of Waitangi. Maori are opposed to no-take reserves because they want to
exercise their traditional fishing rights.
Zealand Department of Conservation's strategic business plan for 1998/2002 In New Zealand, the Department
of Conservation is in charge of no-take marine reserves. Its strategic
business plan for 1998/2002 sets the following goals for achieving marine
heritage protection, based on recommendations by the Australian and New
Zealand Environment and Conservation Council (ANZECC 1998):
establishing a representative
network of protected marine areas.
effectively managing all marine
providing the greatest practicable
protection to migratory cetacean species.
reducing fisheries bycatch of
seabirds and marine mammals.
Johannesburg WSSD World
Summit for Sustainable Development, 2002 (Oceans and fisheries)
Encourage the application by
2010 of the ecosystem approach for the sustainable development of the oceans.
On an urgent basis and where
possible by 2015, maintain or restore depleted fish stocks to levels that
can produce the maximum sustainable yield.
Put into effect the FAO international
plans of action by the agreed dates: for the management of fishing capacity
by 2005; and to prevent, deter and eliminate illegal, unreported and unregulated
fishing by 2004.
Develop and facilitate the use
of diverse approaches and tools, including the ecosystem approach, the
elimination of destructive fishing practices, the establishment of
marine protected areas consistent with international law and based on scientific
information, including representative networks by 2012 .
Establish by 2004 a regular
process under the United Nations for global reporting and assessment of
the state of the marine environment.
Eliminate subsidies that contribute
to illegal, unreported and unregulated fishing and to over-capacity.
Representative networks From the above, it can be seen that marine conservation is still in
its infancy. However, Dr Bill (W J) Ballantine from Leigh, came up with
a proposal that enshrines the essence of a marine reserves system:
representation: marine reserves representing all habitats in all
climate zones. A bit of everything everywhere (diversity).
replication: to have a few duplicates of each type, by way of insurance.
bit extra (overcapacity & replication).
networks: marine reserves to be located 'within reach' of each other,
so that they may reinforce one another. Not few and far between (connectivity).
sustainability: the network and each node to be large enough to
be sustainable on its own, regardless of the condition of the area outside.
must be able to seee it on a map of the country (overcapacity).
f212116: Dr Bill Ballantine
It is not surprising that these principles correspond roughly to nature's
way of achieving resilience, as discussed in Resource
resilience = diversity + overcapacity
+ replication + connectivity + adaptability. It suggests that adaptability
should be added to Bill Ballantine's list; adaptability to changing circumstances
and flexible management.
The amount of the sea proposed to be set aside, ranges from 10 to 50%,
depending on the arguments brought forward. Those clamouring for 10% see
it as an insurance policy. Those tending towards 50% see it as an alternative
to failed fisheries management. Using New Zealand as an example, we'll
have a look at what is involved to implement Bill Ballantine's proposition.
All climate zones, and replication
Countries with a west coast and an east coast, which are also stretched
north to south, surrounded by isolated islands, have a large range of marine
climate zones or biogeographical regions. The map shows those for New Zealand.
Currents on the west coast are cold currents; those on the east coast warm
ones. Just south of NZ the water temperature changes suddenly, south of
the subtropical convergence, waters becoming subantarctic. The Kermadecs
are a specialised case of subtropics, north of the Tasman Front.
In all, there are eight marine climate zones, distinguishable by the organisms
found along these coasts. We thus need at least 8 reserves, and when including
some duplication, at least 16.
habitats The coastal benthic (bottom) habitat zones continue past the littoral
(intertidal), down the sublittoral, which includes various habitats, from
rock to sand and muddy bottom. Before it descends into the trench, four
other habitat zones can be distinguished, all present around New Zealand.
The deep pelagic habitat (oceanic), has an equal number of zones, as shown
in the diagram. These zones are again represented by seamounts, rising
from the ocean bottom to a few hundred metres depth, and within reach of
fishing gear. Such sea mounts have been discovered to house a most varied
community of fragile and long-lived deep water species, now targeted for
protection. Note at this point, that deeper than 200m, the water temperature
is about the same everywhere, so that tropical sea mounts have much the
same habitats as subantarctic ones.
Where the coast is protected by outlying barrier islands, the coast
is subjected to a varying degree of wave exposure, with its accompanying
variety in marine environments. Several marine reserves are then needed
to cover this kind of variety, which is not found on land.
Closer inshore, are found inlets and estuaries, each with their own
water flow characteristics. At times, and by careful design, a single marine
reserve can cover several habitat zones such as an inlet, a beach, a sandy
and a muddy bottom, an exposed and a sheltered reef. Benthic reserves can
cover both mud and sand flats and rock flats in a single area.
In all, our figure of 16 must now be multiplied by 2 or 3 for carefully
chosen large reserves and 4-5 for small, randomly placed reserves. Thus
the total number for New Zealand must be at least 30-70, according to this
Sustainable networks If it is true that fish larvae do not travel further than 100km, then
marine reserves should be located no further than 100km apart. New Zealand's
coastline is about 15,000km, which demands 150 marine reserves, spread
evenly around. In order for a marine reserve to be sustainable, it should
be sufficiently large. Experience has shown that 5-10 km2 is insufficient
by far, and 50-100km2 is to be preferred, which surmounts to squares of
10km on edge. By this reasoning, a marine reserve should extend for about
10km, spaced by 90km of open access, amounting to 10% of the coastline
in 150 reserves, or 150 x 100 = 15,000km2. New Zealand's entire land area
is 270,500km2. Our coastal reserves would thus amount to just over 5% of
the land area.
The folly does not stop here, because more and more scientists are now
saying that marine reserves should not be separated by more than 20-30km
and that 20% of the coast shoule be protected. For New Zealand this would
add up to 900 coastal marine reserves!
Larger reserves can be created in the open ocean within the Exclusive
Economic Zone (EEZ), which in itself measures 14 times our land area, or
around 1.2 million square nautical miles (= 4,100,000 km2). The Kermadec
Islands marine reserve consists of 4 circles extending to the territorial
limit (12 nautical miles= 22.2km), or almost 7,500km2. To cover our EEZ
with 10% in reserves, would amount to 550 additional reserves of this size.
These figures, and the amount of management and policing it requires,
look rather silly. Proponents for 20% in marine reserves, make these figures
look worse still. But the main question is, whether the public will lend
support for such extravagance, and pay for its maintenance. After establishing
the first marine reserve in Leigh in 1975, some 15 followed in the pursuing
25 years. Politicians now want to set aside 10% of the sea by the year
2005! Others will argue that we cannot afford not to. Common sense, however,
says that the benefits do not outweigh the costs.
Rotational reserves What about closing areas of the sea temporarily for a few years and
then reopening them again while rotating such areas? What benefits and
costs would be involved?
The main advantage is that areas of the sea are not permanently locked
up from fishing and that their recovery is returned to fishermen in
its entirety, whereas permanently closed areas return only a small
However, the slow growing species will be unable to reach spawning age
(groupers and sessile filterfeeders like corals). Habitat recovery may
take longer than fish recovery, however sandy/muddy habitat recovers quickly..
Rotating marine reserves thus will not be able to reach their full potential.
Rotation areas need to be very large in order to be effective, which
may be socially unacceptable to subsistence fishermen having to
travel much further out.
People have to be informed of rotational changes and they have to
comply, which may take some time. They have to learn to know where it is.
For managing very large areas with few fishermen such as the Grand Banks
in the Atlantic, rotational closed areas may provide a solution, but for
coastal situations where many small fishermen are found, they are too invasive.
an historical perspective
map shows the North and South Islands of New Zealand side by side, and
all terrestrial and marine reserves, to scale. It also shows in black the
areas which consist solely of bare rock or ice. Click on the map for a
version. The marine reserves hugging the coastline, have been drawn
in red, but arrows are needed to show where they are. In all, there are
an impressive number of 19 marine reserves, but when school children (9-11
years old) are shown this map, in order to give a report card for our conservation
effort in 25 years, they give it their thumbs-down. When asked whether
these marine reserves would have an influence on the environment, they
unanimously say no. If we had ten times more, would that make a difference?
After some hesitation they again don't believe so.
The land reserves or national parks as we
call them, symbolise our first efforts in conservation, and today we are
proud to have them, as witnessed by the many overseas tourists who come
here for tramping, camping and canooing. But these parks have a number
of things in common:
inaccessible: they consist of steep terrain, difficult to penetrate
by foot and impossible by mechanised means.
unlivable: one could not make a living there.
unproductive: they are located over barren soils with too cold,
too wet or too dry a climate. Much is covered in ice and snow.
unmillable: although trees were there, they were often inferior,
and they could not be pulled out.
unfarmable: the soils are too steep and unproductive for farming.
So these national parks are in essence useless
tracts of land that we could do nothing with. We could not even give parts
away to returning servicemen after the war. But they could be 'fenced off'
and set aside. Conservation was thus an accident meeting no opposition.
It is a fact that most productive land has now been deforested and milled.
The very prime of productive land has even been paved over by cities and
roads. We have no sizable parks of the woodlands that once stood where
productive farms extend today. The extensive forests of kahikatea
swamp cypress have been cut up entirely to make butter boxes. A few forests
of the giant
kauri tree have been preserved by private initiative.
Then the Department of Conservation almost allowed this precious heritage
to be destroyed by the introduced possum from Australia. In the
mountains various species of deer roam around, destroying the native forests
and mountain vegetation. Everywhere introduced predators like feral cats,
stoats, rats and even dogs, threaten the native birds who have not evolved
to cope with predation. So the essence is, that everywhere on land, the
threats remain, also inside national parks. Conservation there is thus
f022119: people visiting a marine reserve with a dive mask
on, will see the environment underwater. Expecting to be fed a little,
many fish surround them, creating the impression that the reserve is a
pristine place full of friendly fishes.
f022914: for those unable to go under water, a glass-bottom
boat may provide first-hand experience.
f960810: Seafriends runs educational programmes for school
children. Here they are shown the wonders of the intertidal zone. In order
to minimise damage, we now ask students to go bare foot.
f214320: in high spirits and full of expectation, school
children descend to the beach, dressed in full protective wetsuits.
f214323: before going into the water, they get instructed
about how to use the gear, what to do and not to do, and what our safety
rules are. For most it becomes an unforgettable experience.
f980424: the adventure begins. For many it is their first
time in the sea. In a short time they learn to rely on the flotation of
the wet suit, and how to use mask and flippers. All the time, fish are
swimming around their legs.
In contrast to terrestrial conservation, marine
conservation was an entirely new idea, meeting fierce opposition, because
accessibility: the sea is a flat surface, of which every part is
accessible by boat. Where it meets the land, it is accessible from two
productivity: the sea is productive everywhere. There are no places
too cold, too dry or too wet.
harvestability: what is produced can easily be caught and transported.
ownership: the sea is owned by nobody but used by many. It cannot
be fenced or parcelled and handed out to people living on it. It acts as
a commons, fished to extreme, because if you don't someone else
But as seen before, the sea is worthy of protecting, because:
nobody is living there
habitats have not been changed for farming, roading and dwelling
most species are not harvested
some species are overharvested, needing protection
no introduced species like possums, cats, dogs, stoats and rats are found
In the early 1970s, the idea of marine
conservation was born, first for the purpose of scientific research, but
the idea widened to include the environment as benefactor, and indeed people
too. Today, the concept is marketed to the public on the premise of overstated
direct benefits to themselves, and immediately. The concept is very attractive,
it protects all species: no exception is made.
it doesn't cost much: only some paperwork, some signage and a law
change is needed.
rules are simple: no-take!
we all win: there are immediate benefits for fishermen (not
true), scientists and the public. There are long-term benefits for
our children and theirs.
That marine reserves have
found general acceptance today, is borne out by the 1300 MPAs established
worldwide by1998. The dates for some of the better known ones are: 1935
Florida Keys, 1936 Gt Barrier Reef, 1941 Phillipines, 1958 Bahamas, 1960
Mexico, all in mostly tropical seas.
Back in the seventies, the failure of fisheries
management was overly demonstrated by the collapses of one fishery after
another: mussel, crayfish, scallop, oyster, orange roughy, snapper and
so on (in NZ). Marine reserves would take this threat away, and the
concept was powerfully simple. But after the mid-eighties, the situation
had changed considerably. The Labour Lange Government under new-right policies
of laissez-faire, had abolished the subsidy on fertiliser 'to
remove price distortions' and 'to level the playing field'.
Aerial topdressing stopped almost completely, and a few years later the
hill country began bleeding into the sea. At around the same time our climate
changed, and rains began to pour down in a tropical way, theirrain drops
causing considerably more impact damage than usual on the bare soils, which
were starved of fertiliser. At the same time, other subsidies for pest
control were phased out and possums took reign. It resulted in accelerated
coastal erosion. Encouraged by new markets, farming moved from sheep to
dairy (milk cows), and fertilisers were applied generously to meet demand.
These leached into waterways and into the sea. The new economic policies
required immigration of wealthy asian millionaires with their numerous
families, leading to a population increase, and with it a disproportional
increase in waste and human sewage. While developing the land for shops
and buildings, it became customary to landscape the soil on a grand
scale, using an ever increasing number of earth moving machines. To sum
it up, the land suddenly, in the course of only ten years, became the sea's
number one enemy, and it is still getting worse rapidly. In November 1998,
85% of the crayfish in the Goat Island marine reserve demonstratively walked
out due to filthy waters, only to be caught outside in no time at all.
reserve has proved successful because the fish spilled over" said the
local fishermen and the matter was laid to rest. (See also Conservation/Lessons
f004414: view of Goat Island in the marine reserve near Leigh,
New Zealand. It is an idyllic spot with exceptional qualities like clear
water, shelter, many habitats, rich biodiversity, and safe swimming. Here
divers are seen doing their final sea tests before the Christmas holidays.
The coastal Pohutukawa trees are in bloom.
f013205: since about 1990, mud started to enter the marine
reserve, which had not been seen before 1980. This mud kills those marine
creatures that are unable to swim to safer waters. The environment degraded.
Filthy seas are not an entirely new phenomenon.
In the early 1900s, farming in the South Island has seen its share of dust
storms and swollen muddy rivers, rabbit plagues and degrading tussock
(a kind of rough grass) lands. When all is said about it, one cannot escape
the impression of a massive ecological disaster unfolding over New Zealand.
A new threat (heavy rain) over degrading soils, becomes a two-fold disaster:
we are not only losing our precious soils, belonging to our children and
theirs, but we are also losing our coastal seas, belonging to them too.
Is this stupidity or fate? For this reason a large chapter on this web
site has been devoted to soil and
The bottom line is that a new threat, and a bigger one than extraction
(as proved by the crayfish walk-out), and less controllable, is wreaking
havoc to our coasts, including our marine reserves, which cannot protect
against it. A recent survey of our marine reserves by myself, has shown
that most are degraded and degrading, and not worth having. See marine
reserves index. It has become clear that we must change our focus in
order to effectively save the seas, but above all we need to be honest.
by saving the land, can we save our seas. Floor Anthoni, 1990
Cheaper by the dozen
In New Zealand the marine reserves
issue has become a political hot potato, with protagonists clamouring for
the moral high ground. We have major political parties talking about 20%
of our seas in marine reserves, within a time span of less than ten years.
We now have departments with budgets, whose sole task it is to create new
marine reserves. In business-speak, the Government 'purchases' marine reserves
from them. We now create marine reserves at any cost. It has become a numbers-game.
In the meantime, the bureaucracy and some marine scientists have been dishonest
to the public. The benefits they promised have not materialised and it
is clear that they cannot ever be produced. We have over half our marine
reserves located in the bad-lands of the sea, deteriorating year by year,
without any hope of ever improving. We have deceived the public, and how
long can this go on before they find out and withdraw all their support?
We have become obsessed with quantity rather than quality.
is marketed overseas as a 'green and clean' country, with hundreds of millions
of dollars spent on promotion, marketing and advertising. In the end, even
our own people have started to believe this myth. To say the opposite and
to raise a voice of caution is now akin to blasphemy or high
treason. It threatens people's jobs and incomes and the economy of
"The picture of conservation
that I found in New Zealand, Australia and Malaya was distressingly familiar.
Small bands of dedicated, underpaid and overworked individuals are fighting
a battle against public apathy and political and big business chicanery.
By and large people are only apathetic because they do not realise what
is going on, but the most dangerous part of the problem is political apathy,
because it is only at the top level that you can get things done."
Gerald Durrell in Two in the bush, Collins 1966.
The majority of nature reserves is far too
small to support viable populations. Gilpin and Soule, 1986: Minimum viable populations.
So many land reserves,
but so few in the sea
A main argument brandished in
favour of marine reserves, is that we have so many land reserves (over
1000 in NZ, covering about 10% of the land area, some say 30%), but so
few in the sea. Thus it is reasonable to have as many sea reserves. So
our 25 years of effort, resulting in no more than 19, is only a poor beginning,
and we should have many more. The whole idea of land reserves, is to take
them out of private ownership, so that they cannot be logged, burnt or
built on, which would alter their environment irreversibly. The State will
then look after them in perpetuity. Likewise, a sea reserve is taken out
of the commons (no ownership), into public ownership for protection. However,
since the sea is not under threat of deforestation, burning, logging or
development, which results in a major change (destruction?) of the environment,
the argument has little value for sea reserves. Also remember that the
sea does not harm land reserves, but the land harms sea reserves. Sewage
does not flow up-hill to soil montane parks. Our national parks are essential
useless tracts of land that are inaccessible and unproductive, but our
seas are valuable, accessible and productive everywhere. So there exists
an important difference between the two, and the argument has no foundation.
Since land reserves have
been created for many reasons (lookouts, unused bits of road, scenic, parks,
farm parks, beaches, mountains, glaciers and even mining and logging),
the reasons for having reserves in the sea should be equally flexible,
it is argued. But the number of different uses we make of the sea, is much
more limited: taking, farming and looking.
Saving marine biodiversity
A consensus appears slowly among scientists, about how to achieve marine
conservation, although it is not clear which actions are least costly while
regulating land-based and maritime sources of pollution: by setting
standards for water, sediment and air quality, it is hoped that these threats
can be controlled. A distinction must be made between point-sources (factories,
milk sheds, ships, refineries, sewage, dredging, dumping, spills, etc.)
and non-point-sources (storm water, exhaust gases, farm chemicals, fertilisers,
mud, acid rain, etc.). The first is best done by regulation, but for improving
the second, we must all play our role, and education appears more suitable.
It is claimed that this kind of pollution control is effective and broad
ranging but does not protect specific marine species and ecosystems. It
is not obvious whether dense cities are worst offenders, or the sparsely
populated agricultural land, which is much larger.
integrated coastal zone management: rather than managing the sea
(and reserves) separate from the land, one should integrate the two, in
order to minimise the impacts of an exploding human population and its
accompanying development. This recognises the interrelated functions of
the coastal zone and has been successful in cleaning up the Thames, Rhine
and other. For instance, when creating no-take marine reserves, the nearby
catchment areas must also be considered.
direct regulation of marine resources: the classical approach of
fisheries management, but perhaps extended by allowing more areas to be
managed locally, such as a cockle bank inside an estuary.
regulation of harmful fishing technologies:
nearly all fishing methods have harmful side effects. Trawl nets scrape
the bottom and catch dolphins, seals and turtles. Longlines catch sea birds.
Driftnets catch dolphins and billfish. With more inventiveness and some
regulation, all methods of fishing can be made more environmentally friendly.
However, there would be fewer problems if more
fish was left in the sea: fishermen would spend fewer days at
sea, do fewer and shorter trawls. Wildlife could find its food more easily,
being less inclined to steal from a fishing operation, and being caught
in the process. It is a simple method with double-edged results.
establishment of marine protected areas: some marine protected areas
are needed for their obvious benefits.
use of economic incentives and disincentives: incentives can
be used to encourage exploitation while fines can be used to discourage
pollution. But a system of subsidies could be put in place to discourage
people from doing what they think is normal:
not building on coastal land: living near the sea has its dangers,
although these do not eventuate frequently enough for people to be aware
of (tsunamis, hurricanes, erosion). Subsidies could discourage people from
moving into sensitive areas.
subsidies to fishermen for not harvesting: it is a very good idea
to give the sea a rest now and then, particularly to rebuild stocks. Fishermen
could be persuaded to leave the fishery, which would reduce the pressure
on fishing. Something similar has happened in farming, where small farms
have been amalgamated into bigger ones, and farmers to retire, with the
help of Government.
subsidies to farmers for not cultivating certain lands: Farmers
respond well to subsidies, because their profit margins are low, particularly
on lands that are marginal. Exactly these lands need the most care. Land
is a precious commodity which must last in perpetuity. One could say that
it belongs to our children and that we only borrow it from them. So the
care of the land is of utmost importance, often underestimated. Subsidies
for fertiliser, applied to marginal lands, is an important step towards
conservation. (See soil/erosion)
education: nobody wants to pollute his own environment. It happens
because people are ignorant of the consequences of their actions. Education
is a powerful step towards winning people's support and changing their
attitudes. Best Available Techniques (BAT) and Best Environmental Practice
(BEP) are efforts to encourage industries to educate their members. Integrated
Pollution Prevention and Control (IPPC) is another initiative, all supported
by the United Nations.
monitoring its effects: the effects of our actions towards saving
the environment must be monitored and their cost-effectiveness assessed.
We need to be honest and have the courage to rescind (cancel) controls
which are not working. We must be measuring pollution levels, mapping point
sources and sensitive habitats,and monitor adherence to quality control
international co-operation: by working together on an international
scale, nations can learn from each other's experiences and knowledge. Environmental
laws and methods can be standardised across the world. International agreements
work across national boundaries.
For a more complete treatment on environmental action, visit GPA-
UNEP's Global Programme for Action. (Words are easier than effective and
timely action). Note that only 40 years ago, all the above-mentioned activity
would be of minor importance. Expecting the world population to double
in the coming 40 years, it is unimaginable how regulated living will become.
In every sea-bordering nation,
large tracts of sea have always been off-limits for fishing and anchoring.
In New Zealand, these are the de-facto marine reserves, created for international
shipping lanes, cable ways (1650km2), ammunition dumps (1344km2) and more.
In New Zealand, a total area of over 3000km2  has been prohibited this
way for trawling and anchoring. This is a huge area compared to the total
area in 16 coastal marine reserves of less than 150km2. One would have
expected scientific research to have been conducted in these areas, for
the benefit of knowing their importance to fishing and biodiversity, but
in the almost a whole century that these areas have been available for
such study, this has not eventuated. What's more, the fish stocks in these
areas have declined like they have done outside, making the whole concept
of marine reserves in our coastal seas, questionable.
 Setting Course for
a Sustainable Future. Report of the Parliamentary Commissioner for
the Environment, 1999 p37.
The main two stake holders in
fishing (and thus conservation) are the commercial and the amateur fishermen.
They blame each other for the demise of the fish stocks. Since one of the
things a marine reserve does well, is to separate stake holders (takers
and lookers e.g.), the idea arises to have reserves for amateur fishermen
only. Their task is now to manage these areas such that fishing there delivers
the most pleasure and yield. They will make the rules, without interference
from others. This will face them with the consequences of their actions,
while allowing scientists and fisheries managers to measure the effect
amateur fishermen have on the environment. In New Zealand, the Hen and
Chicken Island group off Whangarei would be an ideal testing ground, because
the Poor Knights (nearby) has been taken from them as a no-take reserve,
and fishermen like to anchor their boats in the shelter of islands and
the mainland's coast.
Likewise, an area could be
set aside for spearfishermen. It will give them the responsibility to devise
rules to keep fish while eating them too. The Aldermen Island group, out
from the Coromandel Peninsula, would be ideal since it has already suffered
major damage from spearfishing.
Much of our understanding of marine reserves comes from imagining a kind
of Garden of Eden (paradise) under water, a place with clear water,
bountiful fish and wise old fish as well. When we visit one of our coasts
today as a diver, we often experience something entirely different. Not
only does the sea seem deserted, it also looks like an untended, withering
garden, with dust covering the few bottom dwelling species that are left.
Those people who never visit the sea with mask and scuba gear, find it
hard to imagine what the seascape looks like. Yet even those who do so
frequently, find it hard to believe what the sea looked like long ago,
when told by veteran divers, now about to die out. Children snorkelling
in the shelter of Goat Island, are enraptured by their experience, being
able to meet friendly fishes so close by. But all these people have one
thing in common: they want to preserve the sea as they have known it. This
raises the question whether we want to roll the clock back 50 years, or
freeze the present situation. What would we need to do to achieve the one
objective or the other or both? No-take marine reserves have been toted
as the one and only tool for this purpose. But the assertion goes further.
Marine reserves can also provide fisheries benefits because fish spill
over from the area of plenty to the area of poverty outside. It all sounds
plausible, but how can we understand it in an objective way? We do so by
the theory of the economics of exploitation. (See Resource
management/economies of exploitation)
In order to stay with a familiar picture, we'll use the same diagram as
presented in the chapter on Resource Management. The basic assumption is
that a marine reserve can be thought of as a single population, although
in fact, it consist of a large number of interacting populations, each
grazing or predating on the other. When a place is almost entirely denuded,
then left to recover, most of the quantities measured, like number of species,
number of individuals and sizes, follows a logistics curve as shown in
diagram A. This shows the quantity measured from low to maximum (empty
to full) against a time scale in years. Recovery seems to proceed slowly
in the beginning (years 0,1,2, the exponential phase) but it is
in fact an explosive growth since recovery is not limited by restrictions
of space and food. In the middle of the curve, growth rate is at maximum
(maximal growth phase), after which it evens out because of lack
of space or food (). Note that this part of the curve is seldom reached
because all populations are kept in check by their natural exploiters.
A pristine environment thus never reaches the max level. Notice
the last (orange) step between year 4 and 5, which is about 25% of max.
This suggests that in order to fish sustainably, we should not fish the
stock down past 70-75% of its natural level. Even so, this would make life
difficult already for other predators like dolphins who do not possess
In diagram A the growth curves are shown for a fast growing population
(purple), medium growth (red) and slow growth (green). Think of them as
the silver fish, the reef fish and the large predators. Diagram B shows
growth horizontally, rather than time. As can be seen, growth is maximal
somewhere near the middle. Note that in an ecological sense, growth equals
a gain in stored energy. The blue line shows the effort (energy) required
to fish from the three populations. Where the line intersects, more energy
is gained from exploitation, than lost in the effort of exploitation. This
then leads to diagram C, depicting the amount of energy gained or lost.
Clearly, all species must gain more energy than they expend, or else they
would die. So they are able only to exploit the stock down partially, which
proves that natural populations are self stabilising. Note however, that
food is not always easily available all year, so many organisms have alternative
The diagrams now continue with the situation for shark (D) and dolphin
(E), not relevant now. But the last diagram (F) shows that human technologies
have given us the power to exploit the stock right to its zero level, also
because the rewards for our effort go up as the catch comes down and the
price goes up. Humans have thus gained the power to destroy the environment,
which no natural organism has. Fishermen often do not realise how effective
their fishing methods have become. For instance, which natural hunting
predator has a mouth hundreds of metres wide and half that tall? Trawling
nets and purse nets do. Which natural predator attracts its prey by odours
from food, from hundreds of metres away? Line fishers and pot fishers do.
Which natural ambushing predator has a mouth tens of thousands of metres
long and fifty metres deep? Gill nets do.
It is this awesome technology that allows us to exceed Maximum Sustainable
Yield (MSY), somewhere in the middle of the curve, without us even
noticing. Yet exceeding MSY means that the stock is being fished down,
unable to restore itself to a healthy state. Note in this respect that
nature has some invisible de-facto protection mechanisms like inclement
weather, high seas, remoteness and unproductivity which leave many stocks
relatively unfished. Having marine reserves in such areas makes little
sense. However, close to populated areas, the sea has often been fished
to extinction. The effect a closed area has, will thus be highly dependent
on where it is located. A closed area on a heavily fished coast with clear
water, will show spectacular recovery, whereas one located far away or
in dirty water, will not. Obviously, if a marine reserve is small, its
recovery will have but a small effect, due to fish leaking out.
We now come to the question of how much is
spilling out to please fishermen? To answer this question, we treat the
reserve as a single population, and leakage from the reserve as predation.
It can now readily be understood that leakage should not exceed 25-35%
of the stock if the reserve is to remain sustainable. This quantity is
in fact equal to that of a sustainable fishery. In practice, such spillout
is not possible, since natural predation inside a successful reserve is
higher than outside, and many resident species do not migrate easily. The
spill over from a no-take marine reserve can thus theoretically never equal
or exceed the lost fishery! This argument is often lost on protagonists
when they clamour for marine reserves as fisheries management tools. Note
that actual measurements of spillover are supporting this. But there is
In order to protect slow-growing species (green curve), marine reserves
must prevent spillout even further by creating disproportionately large
marine reserves with wide buffer zones. These will protect old groupers
and some itinerant (wandering) species, and provide for a healthier age
structure. The problem is, that such reserves spill proportionally less
fish out than those of minimal size. A good, sustainable marine reserve
thus should not return more than 5% of the lost fishery! Marine reserves
are obviously unsuitable as an alternative to fisheries management. But
there is another problem.
Driven by the ideology of fisheries management with marine reserves,
protagonists reason that networks of protected areas may be able to achieve
this. It is thought that if marine reserves are kept small to maximise
spill-out, then perhaps by having many of them within reach of their offspring
(spawn, larvae), will make it work like one larger protected area. However,
this does not alter the ecological reasoning set out above, and the total
leakage from such a network should also not exceed 5% of the lost fishery.
Having many small protected areas furthermore complicates their integrity,
management and policing. Obviously, even networks of no-take protected
areas are not an alternative to fisheries management.
Reader, please note that the above is not mainstream marine
science, but derived from economic laws. It is the first time that clear
evidence is presented of the quantity of the spillover effect, based on
ecological principles. Please contact the
author for comments or improvements.
Marine reserves are thought to benefit areas outside by their larger contribution
to the offspring of fished species. Indeed measurements show that there
are more and larger fish inside than outside. Their combined spawn mass
has been calculated to be three times larger or more. As larvae are dispersed
by ocean currents, tidal currents, eddies and wind-driven currents, they
will mostly leave their origin, to settle somewhere outside. If more larvae
are produced, then more will settle outside, where fewer predators are
found. Thus the benefit of a closed area may reach far out.
Scientists are working all around the world to get a grip on this, and
to prove where larvae originated from. They use sophisticated techniques
such as DNA analysis, otolith marking and more. However, results are still
elusive, and the theory remains unproven so far. Because there is a problem.
Planktonic ecosystems are the least understood environments of all,
because their communities move fast with ocean currents; their organisms
are minute, fast growing and short-lived. Some organisms are simultaneously
plant, animal and bacterium. The green soup contains guilds (functional
groups) of all kind: plants, grazers, predators, viruses, larvae of nearly
all marine species, decomposing bacteria, nitrifying and denitrifying microbes
and much more. Furthermore, the plankton ecosystems over the continental
shelves live in close interaction with the sea soil and myriad organisms
contributing their spawn. In this natural orchestra, timing is important
as barnacles deliver their spawn right when larval food has become plentifully
available, and so on. The fish larvae of fished species are but a tiny
section of this orchestra. But there is another problem.
On land, animals produce limited offspring because to do otherwise would
be wasteful and excessive. Mammals give birth to one or a few babies, insects
to hundreds and plants to thousands of seeds. Some of these produce fruits
to help dispersal. But in the sea, both animals and plants reproduce profligately
(wastefully) to the extent that for most species less than 0.01% of their
spawn will ever produce a replacement (recruit). Such waste is needed
to convert the sunlight into ever larger food particles, in stages, which
we call the food chain. Whereas on land two or three stages from
grass to sheep to wolf are common, in the sea this consists of many, from
phytoplankton to zooplankton, to larvae, to small fish, to bigger fish,
to predators, to apex (top) predators. Even the zooplankton has many stages
as many larvae grow over ten million times before they leave it, to settle
out where they belong (recruiting). So, the path from spawn to recruit
to adult is one of extreme waste and extreme uncertainty. It can be said
therefore, that marine creatures spawn mainly to make food (over 99.99%)
rather than offspring (less than 0.01%). Note that small fishes such
as triplefins cannot afford this kind of waste, and they have resorted
to various means of nest care. Note also that predation (exploitation)
is very natural in the sea, reason why many fisheries have survived human
onslaught. But where does that leave the additional spawn mass from marine
The whole planktonic ecosystem, although oscillating wildly, is on the
whole looped back (effects influencing their causes) in many mysterious
and unknown ways. For instance, as the predators in a marine reserve increase,
and with it their spawning mass, the spawn of the creatures they feed on
decreases, and thus the food for the predators' larvae. For instance, snappers
eating sea urchins will reduce the urchin's spawn, which causes a major
decrease in the total spawn from the reserve. Urchins are closer to the
base of the food chain, grazing on fast growing algae. Because they do
not spend much energy in moving, they produce disproportionately more spawn.
Because predators move around, while wasting energy also in other ways,
they must eat many urchins in order to gain the energy to produce the spawn
equivalent of one urchin. As a result, the larger fish decrease the total
amount of spawn from the reserve, which also reduces the food for their
own larvae. In all, the whole issue of larval production and dispersal
remains academic and of little value to fisheries.
Thistles are invasive weeds, quick growing, fast seeding plants which propagate
over vast distances by the shape of their seeds. These bulk up by a network
of fine hairs, so that they can be carried by the wind. It is amazing to
find them crossing the sea for 40km, to arrive at a remote island. The
fluffy seeds are called thistledown.
Marine organisms have a
similar advantage, because their eggs and larvae are carried in the water,
while sea currents transport them far away. Fish larvae can travel 50-100km,
and 'stragglers' may arrive from warm waters, 1000km away. The thistledown
effect is claimed to give marine reserves a disproportionately large advantage
as a source of tiny colonisers, acting like an insurance. It is
reasoned that even a small reserve can produce a lot of larvae, an acceptable
assumption because fish there are about twice as numerous and larger than
outside, producing three times or more eggs. Large fish can produce over
a million eggs each, by far enough to restock the entire outside, one may
However, this is not how
nature works in the sea. A vast overkill in larvae (from all species and
phyla) is needed to convert the energy of the sun into parcels of energy
(little fish) that are large enough for sizeable fish to eat. This happens
in stages, which we call the food chain or food web. Thus a predator fish
in the end, lives from food produced by its own eggs. It illustrates nature's
intricate system of harmony between its many players, and it explains why
so many sea creatures are broadcast spawners, wasting almost all
their eggs in reproduction. It is a survival strategy that, although wasteful
for each, is beneficial for all. Fisheries scientists, accounting only
for some fish species, while believing that a low stock is able to produce
enough offspring, apparently are ignorant of the intricacy of such food
chains. This is one of the main reasons that fisheries worldwide collapsed.
If we wish to save commercial fisheries, we must manage them with larger
and more balanced stocks. Marine reserves would simply not help. The thistledown
effect is a myth, with neither scientific proof nor foundation.
How marine reserves can fail
It is not entirely certain, how failure can be defined. Some people argue
that if a reserve saves only one fish, it is worth having. They do not
seem concerned that an important freedom of the seas, to be able to go
wherever one wants, to take whatever one can get, is taken away from people
making a living or enjoying the sport and thrill of it. People on little
income often depend on the sea for sustenance. Minimising costs by going
out in small boats, these people fish wherever shelter can be found from
waves and wind.
Man has always lived with the sea in close harmony, taking what he needs
from its seemingly inexhaustible larder. The whole marine ecosystem is
a fish-eat-fish world, where predation is common fare on many levels of
the foodweb. Predation by people is just another facet. For time immemorial,
people have lived with the sea this way and this has become the natural
situation. But now there are just too many people demanding their share.
Instead of taking, we have entered the more difficult era of sharing. Now
it is no longer reasonable what one can get, but what one can leave for
Marine reserves aim to save some unspoilt areas for present and future
generations in a state that will not worsen over time. They are like time
capsules, where time stands still. However, many marine reserves have failed.
Why? Here are some important causes, arranged by their severity:
environmental degradation: threats by human activities on the land.
Some 40 percent of the USA's waterways are unsuitable for fishing. Commercial
overfishing, habitat loss, and pollution threaten fish populations nationwide.
mud: due to poor land management, urban development and roading,
the land erodes much faster than under natural conditions. In New Zealand
for instance, much of it disappears about 30 times faster than the soil
can regenerate and some 50 times faster than what was once natural. Mud
in the sea suffocates marine organisms. It changes the structure of the
sea bottom. It also releases nutrients from the fine clay particles, causing
virulent plankton blooms. Such thick soup can become poisonous to many
species from all phyla (main groups). No marine reserve can guard against
this threat. This has become a serious problem in New Zealand and elsewhere,
reason why marine reserves will fail in most of our coastal waters.
agricultural run-off: the runoff from agricultural land contains
next to mud, also excess fertilisers, agricultural biocides and at times
hormones used for meat enhancement. These cause similar problems as described
sewage: particularly where human concentrations are high, the damage
done by sewage can outharm those mentioned above. Even when treated, human
sewage still contains all the necessary nutrients for life, and in powerful
concentrations. It causes severe plankton blooms.
overfishing: An area such as a scallop bed may have been overfished
to the extent that recovery has become impossible. The sea bottom's structure
may have changed such that larvae won't settle there any more. The organisms
may occur in such sparse concentrations that their spawn can no longer
meet for fertilisation (Allee effect). If the area outside has been fished
very severely, the spill out of the reserve may become unsustainable.
poor reserve design: most reserves end up as a compromise to human
needs. Hardly anyone knows the sea well enough to understand what marine
organisms need in order to form sustainable communities. As a result, most
marine reserves have serious shortcomings such as small size, poorly chosen
locations, boundaries, and so on.
poor policing: whenever a reserve becomes successful, fishing inside
will become quite rewarding. If policing is inadequate, poachers can very
quickly cause such damage that the reserve appears to have failed. In poor
countries where policing officers can be bribed, marine reserves are doomed
resentment by the local communities: compliance cannot be legislated
for to be successful. It must primarily enjoy the support from those who
gave up their rights to fish. Consultation, co-operation, retraining, local
management, self-policing and taking part in fish counting are important
ingredients for success. Where marine reserves are managed centrally, they
are doomed to fail.
loss of information: stored information is an important ingredient
of resilience. It is found in the genetic code to grow new organisms, the
age structure and composition of ecosystems and their soils, and it is
found in collective knowledge (fish schools, flocks of birds, herds of
grazers). It embodies day to day knowledge about where to shelter, to feed,
what to feed on, what not to feed on, how to catch and seasonal knowledge
how to migrate. It also teaches how to spawn, where to congregate and much
more. This information can be lost easily, resulting in a species' inability
to recover (Allee effect). It is thus important to protect before an
environment has declined too far.
One thing is certain: if a reserve gets worse over time, it
is not sustainable.
With all the discussion and research on marine reserves, there is still
no method for assessing the health of an area, and whether it is getting
better or worse. Worse still, many researchers are so single-mindedly focused
or so inexperienced, that they are unable to see degradation. This is not
entirely surprising, since one has to learn to see what is no longer
there. Degradation does not readily show in species lists, fish counts
and fish catches. Other methods are needed. As a result, conservation managers
are often unaware that their marine reserves are or have become unsustainable.
For more information, read the section on observing
degradation (planned) and marine reserve design
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