Originally written for an overseas TV documentary crew, this article summarises the marine issues affecting New Zealand. It is the intention to revise this document but for the time being, it could serve everyone because it touches on all isues. At the end you'll find some excellent discussion points for use in the classroom. Remember that more recent discoveries have not been included here.
FROM HUNTER TO CARETAKER
By Dr J Floor Anthoni (1997)
SEAFRIENDS Marine Education Centre
Leigh, New Zealand
|As the twentieth century has drawn to a close, we are becoming painfully aware of the limits we have reached in exploiting our world's resources. Although the sea has always been man's seemingly inexhaustive provider, it has now also come under threat of diminishing fish stocks, polluted seas, and perhaps extinct species. Even in a country like New Zealand with its small population, enormous coastline and vast territorial seas, these problems have manifested themselves, much to our shame and discredit. Whereas mankind has traditionally acted as pillager and predator of the seas as long as fish stocks lasted, we now need to act with much more care. As we are gradually becoming aware of the naked truth of the damage we have caused, we are fortunately also more prepared to learn further about our sea in order to find ways of managing it. From hunters we are gradually becoming caretakers, a challenging and rewarding process that should involve every one of us. This article looks at what is wrong with our seas, what caused it and what we can do to improve the situation.|
|The diminishing resource:
Stupidity or necessity?
Having arrived in New Zealand in October 1975, I can clearly remember how bountiful the fish catches (mainly snapper) were and how cheap fish was in the shops. With the disastrous overfishing of herring in the North Sea still fresh in my memory, I was astounded how little the NZ Ministry of Agriculture and Fisheries had learnt from the North Sea disaster. They proudly published steeply climbing graphs of catch rates and fishing vessels taking part but no alarm bell was sounded.
On the contrary, more people were encouraged to take part. Investment in boats was subsidised. Yet as more and more fishing boats took part and the total catch volume rocketed sky high, the catch rate per boat quickly diminished and soon thereafter the total catch volume also plunged to a rock bottom low; the stock had been depleted through overfishing. We have seen this happen time and again: the Chatham Islands rocklobster bonanza, the toheroa wipeout, the orange roughy tragedy, the mussels of the Firth of Thames, the scallops of Nelson, the trevally from the Bay Of Plenty, the abalone and oysters from Bluff and very recently the grouper and hapuka demise at the Three Kings Islands. Is it so difficult to act and to manage before a disaster strikes? Do all our fisheries need to get into trouble before positive steps are taken? What about our squid, hoki, tarakihi, dogfish, school shark, tuna and kahawai?
Both amateur and professional fishermen can now kill more effectively thanks to the miracles of modern technology. We have more free time, better boats to roam further afield with, videos that teach us how to fish as experts, electronic fish finders that pinpoint fish with frightening precision, spotting planes to locate shoals of fish, while navigating by satellite, being able to trawl the sea bed deadly accurately. In other words, advancing technology enables us to catch fish ever more efficiently.
Before the age of technology and trade, man caught a fish when
he was hungry. As soon as he had eaten the fish, he had no need to catch
any more. It was a stable cycle. But greed and technology changed
all that. Now people catch fish for money. The more fish, the more
money can be made. Technology and trade create the capability to preserve
the catch and to distribute it to a vast market. The cycle has become unstable.
So the future for fish looks grim indeed. But what about all those other
creatures that inhabit the sea, the ones we usually don't eat? Are they
affected by our actions, do they affect us at all and in what manner are
they affected by exploitation of other species? Would a reduction of snapper
cause a reduction of snapper larvae which in turn would change the balance
and nature of the plankton ecosystems? We don't know. The interlocking
cycles in nature are just too complicated. But Marine Reserves could perhaps
|The reserve as a solution for
conservation: a historical perspective
In the early seventies, during the Snapper Bonanza, a new concept was born, that of marine reserves and in May 1977 the first New Zealand marine reserve was opened at Leigh (gazetted in 1975), about an hour's driving North from Auckland. Because I live very close to this reserve and spend many hours diving it, I have observed how fish life changed, how people's attitudes changed and how this in turn affected under water life. But let's first see how reserves were allocated beforehand. The concept of wildlife reserves is not new at all. We have several of them and indeed vast areas of nature parks. However, the reasons for creating reserves have changed over time, mainly because the reasons for conserving have changed and are still changing.
The first reason for creating reserves (about a century ago) was that there were certain useless tracts of land that were simply unsuitable for logging, farming or for mining. One couldn't live there, build there or even get there. Because all bits of land had to be given some sort of designation, these areas were set aside as 'reserves'. Most of these reserves now protect our mountain wilderness. Also the Maoris have donated vast tracts of land to the Crown for preservation, sometimes because they feared that other Maori tribes would sell that land, or do the same. In those days it wasn't at all clear who owned what land. When we come to the sea, the situation is entirely different because nobody owns it whereas anybody uses it and everywhere can it be fished. Just imagine what would happen with one's music collection if anybody uses it but nobody were responsible for it. It would rapidly become a mess. Well, that is exactly what happened to our seas. So, creating a marine reserve is an extraordinarily new concept, meeting unbelievable opposition.
We now have a marine reserve that sets aside a 'useless' area of sea because it is too far away for efficient exploitation: the Kermadec Islands and a large area of sea around it. But this happened only after divers discovered the huge groupers living around Raoul island. Such big groupers must once have lived along the North Island too but they have all been taken a long time ago, perhaps even before the white man arrived here. A grouper is very easy to catch on a normal fishing line. It is an inquisitive fish that is aware of boats arriving and will come to investigate. It is also a lazy fish, happy with its role in cleaning up dead and dying fish and it has a vast territory which it patrols frequenlty. So it takes the bait as a matter of daily routine. Because these fish are thought to live for over a hundred years, it may take a very long time for the Poor Knights groupers to grow as big as those around the Kermadec Islands. (See Kermadecs section)
Tragically enough, because these early land wilderness reserves were originally not intended to protect species or habitats, we therefore have preciously few samples left of the types of forest that grew on economically important and therefore desirable land, or that in themselves were important sources of timber. The kahikatea swamp forest, for instance, is now extinct and only in the nick of time have we been able to save small pockets of stately kauri forest and a small rimu forest.
It was much later that the concept of conservation was applied to retain unique land habitats. Our outlying islands with their clear waters are sufficiently unique to be protected. It makes good sense to protect them now before they get plundered. These islands have escaped the inevitable damage of pollution because they are located just far enough away, but introduced goats, cats and rats have done their harm. Even so, we have been too late to protect the Mokohinau Islands, now severely damaged by spearfishers and crayfishermen and the Three Kings, damaged by unrestrained catching of grouper, hapuka, bass and bluenose. The Aldermen Islands, Mercuries, Mayor Island and White Island have already lost their values.
It wasn't until very much later that we became aware of whole species disappearing because their habitats had disappeared and that they were being killed off by exotic predators like cats, stoats and rats. We now started to wield the weapon of the reserve for preserving animals. In this field some remarkable work has been done, particularly for native birds: the Chatham Islands black robin, the crested penguin, the kakapo, the kiwi, the bell bird, the saddleback and so on. It is telling for mankind's influence that the only way to save these species is by putting them into areas where people are kept out. One could therefore argue that the best way to preserve nature is to put humans in reserves! An example of a marine reserve to protect one species is the new reserve around the Auckland Islands (February 1992), designed to protect the Hooker sealion. It appears that people can be moved into action when there's a fire but not when there's smoke. Conservation has for a long time focused on firefighting, that is doing something when it is already too late. It shouldn't surprise then that the most common conservation efforts relate to the salvation of an endangered species like the Chatham Islands black robin. To save one endangered species like the Hector's dolphin, one needs to know a lot about it: how many are there? where does it live? does it migrate? how does it reproduce? when does it mature? how many offspring can it get? does the population decrease? by how much? how is it threatened? by fishing, as by-catch, as young, by habitat destruction or by loss of its food supply? The list of questions to be answered is almost endless. It would be very impractical to do this for all the thousands of species that somehow need protecting too. But a reserve gives protection to untold many species without us needing to know much detail. It is such a simple and precautionary solution!
As we became more sensitive to the needs of nature and more understanding
of how this conflicted with the needs of mankind, we created new reserves
such as wetlands which, although not protecting a single species, are such
links in the survival of many species but which at the same time are
such desirable areas for town development. We'd like to have marine reserves
also that protect certain habitats and species but here the situation appears
slightly different. First of all we know too little about sea life to
know which species are threatened and finally, for those commercial
fish species in danger of extinction, we merely need to regulate the ways
in which they are being caught. Remember that these species didn't
disappear by themselves through habitat destruction but were fished to
commercial extinction. By stopping or regulating the fishing, it was concluded,
the species should return to sustainable levels. Although this was for
instance true for the fur seal, the whales have never returned and the
toheroa shellfish is also reluctant to make a comeback. And although snapper
and trevally appear to recover, the situation for orange roughy (and possibly
also hapuka and grouper) appears more delicate.
|Regulating the fishing industry
So do we need marine reserves at all when we have other conservational tools at hand? By the way, what are these tools? To understand these, consider the sea as a gigantic farm run by nature while we are culling the flock. It then stands to reason that we must leave some seed stock to grow next season's crop. A farmer would keep about half his flock, as leaving half for next season would be all that is needed. But why half? Because cattle and sheep reach maturity in two years and a mother produces one young each year. What is the situation in the sea then? Snapper needs close to ten years to mature and orange roughy perhaps forty! So in fact we need to leave a higher ratio, perhaps 80 percent or so and catch a lower portion, perhaps 20 percent. Fortunately, however, most fish reproduce prolifically, enabling them to recruit vast numbers in a favourable year but hardly any in unfavourable years. So the mathematics of it all becomes rather unpredictable.
But if we can agree on catching a ratio of an ideal stocking level, then what is an ideal stocking level? The present level or the one before the overfishing started? Well, really we don't know. If we keep levels low then there would be more food for each and the fish would grow faster but recruitment of juveniles would be slower. What all this means is that we should learn more about the sea, be prudent in our catch rates, monitor fish stocks constantly and be flexible in the way we regulate.
The way we regulate our fisheries is quite ingenious and practical. We outlaw methods that leave fish mortally wounded while not caught, such as dynamiting and hooking crayfish but we allow 'by-catches' of fish that died in the trawl net and that are thrown back into the sea or sold for fishmeal. We design mesh sizes to catch only the mature fish and let the juveniles (a high percentage of the stock?) through, although it would be better for nature to catch the medium sizes and leave the big ones alive to reproduce. For the old fish uses its food mainly for reproduction of which it is experienced and therefore very successful. Perhaps one day computer technology may come to the rescue. We also regulate the season for catching so that the fish can devote themselves to the reproductive call of nature while undisturbed by people. Very often fish concentrate during the spawning season and it would be all too easy to catch them then and to wipe them out. So why then did we allow fishermen to catch orange roughy while the fish were schooling for spawning? One reason was that we really didn't know (The Japanese know perhaps more about our seas than we do!) but the other is that all too often we give in to commercial pressure. It is simply the economics of fishing that demands it: rather than spending many days at sea and catching a little each time, it is much more efficient to go out when the fish congregate and to catch many in a few attempts. That makes sense too.
So how do we regulate for that? We do that by allocating quotas. Once
we know the size of the fish stock then we can allocate a quota, a certain
portion of the stock. However, the mistake we made with the orange
roughy stock is that we didn't know how old the fish were on average, a
blunder of the highest order. Now that we know that Orange Roughy grows
very old (80-120 years) and reproduces slowly and unpredictably, we can
see that the past quotas have been damaging indeed.
|The marine reserve to regulate
The main problem with the traditional controls on fishing as explained here, is that we are targeting a specific species in a specific area. It is a very complicated method that requires constant monitoring and adjusting. In our zeal to maximise catches, we are running the stocks at such low levels that no margin is left for errors in our methods, natural disasters and other unpredictable events. In addition, the quota system with its focus on a small number of species, may unbalance our marine ecosystems, which could be detrimental to a vast range of species and ultimately to mankind as well. Marine reserves, which protect all species, would act llike an insurance policy, should the sea elsewhere have been severely damaged by customary fishing practices.
An even better way would be to rotate large no-fishing areas and allow
balanced fishing in the remaining sea. It is much better to catch all species
(including predators such as some dolphins!) across the board rather than
to catch selectively. So when dredging scallops, one should also destroy
the predating starfish caught rather than throwing these back.
|Consequently we shouldn't have marine reserves just to protect an interesting area for diving or to protect a species, we should have marine reserves right across the entire spectrum of habitats, from rocky shores, shallow estuaries and sandy beaches to 'uninteresting' seabeds and the deep sea. Because sealife changes from north to south, reserves must be duplicated in all our marine climate areas. And for it to work, there need to be many of them, and they need to be big, covering vast areas of the sea according to the ratio we wish to set aside for precaution.||
Ironically, because we know so little about the under water environment and where the sensitive hot spots are for which species, it would almost be better to assign marine reserves at random, by throwing the dice, so to say.
Once we have set aside a sufficiently big area for marine reserves, we can relax traditional restrictions on fishing such as mesh sizes, minimum sizes, seasons and so on. Alternatively we might decide to set aside smaller areas for marine reserves but retain stringent fishing regulations.
At the moment the official marine reserve policy is for at least
ten percent of all habitats in all areas, but this requirement must
be weighed against the effectiveness of fisheries regulation, and the effectiveness
of having many small protected areas.
|Sewage, the harmful fertiliser
The thought of locking people up in a reserve and letting nature roam freely outside, has its merits. Of course we are far too late to do so now (although Antarctica is still a point in case) but let's face it, almost everything we do is damaging to the environment, particularly in places of dense population: We have to leave our sewage somewhere and because it flows, it eventually flows into the sea. With it we are losing a valuable resource of nutrients and minerals that could have been used on the land. We have ill-designed our sewage systems, allowing the effluent to be diluted by 'grey' washing water, rich toilet flushes, and often also storm water.
So by the time it reaches the treatment ponds, it is too diluted to be of commercial value. We have no other option than to release it into the sea. Here it could be a threat to our own health, prohibiting us to swim or it could infect our shellfish with human diseases. Although too diluted for us, the 'treated' sewage is often too rich for the environment, causing putrid areas devoid of life and upsetting the balance of nature. Particularly in the cold season when biological activity is lowest, will it cause most damage. The treated sewage effluent is such an effective fertiliser that it causes dense plankton blooms of weird and often poisonous plankton species.
It is important to make a few observations about pollution in general and how it affects New Zealand. Pollution is simply a concentration of resources that is too diluted or too mixed up (like in household waste) to be reusable. Of course the economical dollar equation is the one that says so. In this equation some important imponderables such as quality of life and long-term sustainability are glaringly absent. A vast tract of nature is needed to clean up the mess. Whether this is done in a dump, a treatment pond or the sea is irrelevant to the world at large. For New Zealand it could often be better to pipe untreated effluent far out to sea and let nature do its work there, rather than trying to treat it and then releasing it close to the shore. A better solution would be to ship it out in tankers (treated or untreated) and to spread the effluent over parts of our seas where more nutrients are needed. New Zealand is fortunate that it has few inhabitants and a vast ocean around it with many places where currents lead the effluent away into an enormous ocean basin. We also have a huge open sky and weather that consistently blows our smoke away into that part of the immense Pacific Ocean where absolutely nobody lives. If the world ever decided on the ideal place to burn and recycle its wastes, then surely New Zealand would be high on the list. What I want to say here is that in finding solutions to our problems, we must recognise the unique situation we are in and that therefore our solutions must be different from elsewhere in the world. For us it is better to pipe coalfire smoke directly into the atmosphere than to scrub the chemicals out of it and ending up with yet another disposal problem near our coastal seas. We are in the unique position that we can make money out of the rest of the world's rubbish by burning and recycling it here. Rather than overloading the Northern hemisphere further, it makes more sense to off-load some carbon dioxide into the Southern hemisphere where resources such as our forests and marine phytoplankton can do a better job. Our weather patterns and ocean currents furthermore make it possible to do it in such a way that it wouldn't need to affect us.
A case in point is Wellington's sewage treatment. I have always been
amazed that a city like Wellington can find hundreds of millions of dollars
to build arts centres and museums, yet has no funds to clean up its sewage
mess. That is a bit like driving a Rolls Royce with dirty nappies on. At
Moa Point, where Wellington's shore is beautiful and reflects an almost
Mediterranean character, each day millions of litres of untreated sewage
are piped straight into a basin with hardly any current (the very strong
Cook Strait currents are further out to sea). Adjacent to this spot lies
Island Bay, a beautiful fishing port with desirable beaches stretching
in between the rocky outcrops. This beautiful shore is only a few minutes
drive from the heart of the city and offers the only ocean beaches around
Wellington. Visitors fly low over it when either departing from or arriving
at Wellington Airport. On a stormy day one can see surfriders playing in
what is extensively advertised as a no-swimming area because it is so infested
by bacteria. When taking the ferry, one can see long rafts of yellow poo
floating the Cook Strait. Ironically, because the seafood is dangerous
to eat, the outer areas have become a defacto reserve, a mecca for those
divers who defy the chance of getting infected by human disease. To make
matters worse, the City Council held a referendum with the rate payers
on what solution to take for this sewage outfall. Almost unanimously the
uninformed public decided to first treat the sewage fully before releasing
it, whereas the most practical solution would have been to pump it into
disused oil tankers and to spread it far afield to let nature do its thing
|Soil erosion and farming
Even such a harmless activity as farming, though well away from the sea, has its harmful side effects. In order to keep the land productive, we need to plough it and we depend heavily on the use of fertilisers. Although we don't use a lot of nitrogenous fertiliser which causes severe environmental problems in Europe, the clover plants with their nitrogen-fixing bacteria, produce the same product naturally. We still use lime, superphosphate and potassium.For our soils these supplements give tremendous benefits, even when used in small quantities. But some of these nutrients are in short supply in the sea, reason why they can cause problems there.
Eventually the nutrients end up in the sea where it causes the plant plankton to bloom. In other words we are also fertilising the sea. In very low concentrations this is beneficial because it provides more food for the sea creatures but at higher concentrations it causes dense plankton blooms obscuring the sunlight, resulting in loss of plant life in deeper water. Also unusual plankton species may prosper, causing poisoning and death to fish and shellfish and humans.
Worse than fertiliser are the clay and topsoil that erode from our
farms. We still believe that the steep hills can be farmed but we fail
to see how these hills deteriorate; how the hard rock comes through and
how nothing else will eventually grow but the confounded gorse, the yellow
prickly lupin. After having cleared the land with so much effort, we have
failed to see that the land needs trees to hold it together, particularly
in the gullies where the water gains strength to rip away the future of
our children. It is a problem typical of young countries like New Zealand
where the land was denuded about a century ago. It is also accelerated
by poverty that forces farmers to overstock, paying too litle attention
to what the soil needs.
|But why does all this happen? Simply because it is difficult to
notice deterioration when it happens so slowly. And it costs money
and effort to reforest the new wastelands, to plant trees and to maintain
these amidst the grazing herds. And it takes time to change attitudes.
Roading and land development also leave large areas of soil exposed to
the weather but nowadays these are soon grassed over, which has reduced
the problem somewhat.
In recent years, due to relaxed immigration policies, the population of NZ has been rising rapidly. Combined with increasing wealth it has caused a very rapid increase in waste water, refuse, roading and urban development. Big urban development projects are now required to provide sedimentation ponds to trap the clay particles in their stormwater run-off, but these measures appear insufficient.
Now our children's heritage, the fertility of the land, lies in a thick
layer of volatile clay and mud, deposited in the basins of our gulfs and
continental plateaus, ready to be stirred with every heavy sea, clouding
the water and smothering the encrusting lifeforms on our rocky shores.
We have no idea how much damage has been caused, we don't even know what
our seas used to look like. The old folk's tales of bounties of fish life
close inshore, of clear waters in Auckland harbour seem too unbelievable
to be true.
|Invasions from abroad
Although we are our own country's worst enemy, some of the dangers have come and are still arriving from abroad. We all know the disasters caused by the importation and successful release of apparently harmless animal species: the rabbits that now plague the South Island; the possum that is now intent on destroying the fine kauri forests and coastal pohutukawa trees; the rats and wild cats that decimated bird species and so the list goes on and on. But the sea has had its share of imported problems too.
As the waters of the oceans are more connected with each other than the continents and islands, one would think that sea creatures could move freely from one continent to another. But this is not so.
The vast tracts of deep ocean are impenetrable barriers to most coastal species. Cold water species can't pass the warm equator to go to the other hemisphere. Most of our marine invaders we can expect from temperate seas in the northern hemisphere and they, in return, can expect invasions from us, such as indeed caused by our modest barnacle.
But sea traffic has changed all that. Many species from mainly the northern hemisphere have found their way into New Zealand waters, hiking the hulls of all kinds of boat or hiding in ballast water of commercial freighters and oil tankers or having been brought in on purpose.
In the port of Whangarei near the Marsden Point wharf, one can usually find new arrivals such as crocus-like seasquirts, exotic nudibranchs and massive snails. Fortunately most of these fail to reproduce here or just fade away in the winter cold. Some have taken an unimportant place in our underwater fauna such as the mud mussel and the burrowing lobster, now widely dispersed through the Hauraki Gulf and further North. But the pacific oyster, although bigger and more desirable commercially, is gradually pushing the native rock oyster out of existence.
Our seas have always had the occasional influx of stragglers from Norfolk
and the Kermadec Islands, which makes diving here just that little more
interesting. Although we can identify some of the new arrivals, we have
absolutely no idea of what other pests and diseases have also found their
way to New Zealand. Clearly, we must spend more time and effort monitoring
our seas. But even so, what can we do once an invader has taken hold
on our shores? We can't use chemical means, because that would threaten
so many more species, and we cannot achieve anything with human effort.
We might as well forget about fixing marine invasion problems, and concentrate
on prevention instead. However, the nature of prevention is that it reduces
the chance of accidents, but it does not eliminate the chance altogether.
So, rather than eliminating that it will happen, we are merely postponing
when it will happen.
|Benefits of marine reserves
As is often the case with a new idea, its full benefits come to light only much later. I can still remember the senseless opposition that once existed and was voiced loudly in meetings and hearings about the impending Goat Island marine reserve. But now invariably, everybody has turned in favour of it. The fishermen have seen that they can fish very well along the boundary of the reserve whereas other areas around Leigh have been depleted badly. In the 5 km of reserve, the stock of crayfish has been estimated at half a million animals. The number of crayfish boats, after a sharp decline, has increased again. Every weekend people come from far afield to snorkel or dive in the reserve and to hand-feed the tame fish. The scientists at the Marine Laboratory enjoy the protection of their experiments although they find it difficult not being able to take live samples from the reserve. All these benefits were foreseen when the reserve was created and have worked as expected.
But unforeseen benefits emerged as well. I have been so fortunate to have been involved from the very beginning, diving here in my 'backyard' as I call it. As recently as the late sixties, dive clubs organised bus trips full of spearfishermen to raid the area that is now the marine reserve. These trips ceased when all the valuable fish species had been taken (particularly red moki, snapper and kingfish), so that when I arived in 1976, I found the fish very skittish and wary. The very common parore (mainly speared for target practice) could only be observed as a fast fleeing shadow, swimming at such an angle as to expose only its dark, narrow back. As time went by, the parore allowed me closer and closer until I discovered that it is really a very sociable fish. On a quiet day they would socialise above a bright sandy patch and let themselves be cleaned by a smaller fish, at that time too far away to be identified. Still later I could get so close as to be able to put their social pampering on film and identify the little cleaner as a young trevally.
This little cleaner is more or less a status symbol because only the bigger parore have one and they draw it along with them in an eddy alongside their ventral fin, as they swim. They also take it to bed because at night I would find some, still fussing over their little cleaner mates. The little trevally in return benefits from the protection the big fish offers. By now the parore became so used to people that they were no longer worried at all and with great delight I could observe their every move, how they tore the luscious algae growing on the tough fronds of the long lived carpophyllum seaweeds, how they cavorted in fast schools and how they courted. I saw how they spent a good deal of the day resting and sleeping and they showed me how much confidence they had in my presence, by falling asleep within an arm's length away from me. A little triplefin would come and pick irregularities off their skins and they would change from silver with stripes to black with white blotches along the dorsal fin. What a blessing it can be to dive in a marine reserve!
The reserve allowed me as it undoubtedly did the scientists, to study the normal cycles in nature. It was hard for me to accept that certain species come and go, because I thought of nature as a balanced community that exists in a more or less stable state. But some things changed apparently without reason. The splendid warty brown and blue nudibranch with white fringes (Dendrodoris gemmacea) went and stayed away for a couple of years, then returned. Certain colonial seasquirt disappeared but others took their place. From other places the ecklonia kelp disappeared and the flexweed (Carpophyllum flexuosum) that belongs more to harbours and estuaries, took its place. The seahorses disappeared and this year also the pipefish. The brown mussel beds became depleted too and disappeared. Even for scientists it is difficult to distinguish what is normal and what is abnormal, amongst the various cycles.
The El Niño decadal weather pattern gives a ten year cycle of warm seas with abundance of fish species and cold seas with heavy plankton blooms and destruction. Marine reserves can't protect or level out such variations but they do protect against over-exploitation. The divers also inflicted changes to the reserve. First they fed the fish with sacrificial sea urchins, which upset the balance of nature. It left flat rocks ungrazed with the result of more seaweeds colonising these places. Especially the featherweed (Carpophyllum plumosum) cashed in on this. So the underwater landscape changed, particularly around the most accessible places. Not surprisingly the crayfish were poached from these areas.
As the fish became used to being fed, they started to expect it and became a real nuisance. They were always in the way of my camera and interfered with what I was studying. The marauding gangs of snappers and blue cod would scare the living daylight out of a wary octopus or a shy moray eel. To make matters worse, they would bite and nip me, prodding me to be fed. Often I had to swim a long detour over the deep sand before they would let me go.
I discovered that only the opportunistic feeders such as snapper, spotty, blue cod, kelpfish, leatherjacket became corrupted but not the plant eaters such as parore and neither were the pelagics such as trevally, kahawai and blue maomao interested. But time changed all that as people changed the type of food and the fishes adapted. Now one can see the public waist-deep, bending over to feed the little beggars and the diet contains cereals, frozen peas, dog sausages, bread, salted chips and other junk food.
This activity delights the occasional visitor and is perhaps necessary for being introduced to the magic of a marine reserve. As long as they spoil only the fish near the beach, the serious diver can still find an unspoilt area further afield. Every year a new species joins the list of friendly fishes. One year I was able to film the social butterfish, then the almost impossible marblefish (young ones only though!) and finally last year the fast swimming and utterly shy silver drummer. At the outside of Goat Island we can now pride ourselves in a big school of blue maomao which one day may count many thousands of individuals. I also suspect that the school of massive kingfish (15 Kg each!) is resident to the eastern area and may stay to a ripe old age.
Although the Leigh Marine Reserve is by no means an exceptionally beautiful area such as the Poor Knights or the Three Kings, it delightfully shows what is normal, in abundance and in peace. Even the scientists have changed. Whereas they previously saw the reserve as their scientific laboratory in which they were allowed to do what they liked, they are now keeping to the rules too. They have removed abandoned experiments that littered the area, cables to and from deep water experiments and they respect that from the reserve no fish is taken. The reserve is gradually becoming a 'baseline' area allowing scientists to make comparisons with areas outside.
The real magic of the reserve, however, is that it is totally imaginary. In the water nothing has been changed, neither has anything above. The reserve exists purely in our minds. Once we have set ourselves an invisible rule for how to behave, the rest follows. The fish respond by being tamer and are in fact studying us. Their numbers increase and they feel safer. Big snapper (I've seen one exceeding one metre in length!) migrate into the reserve and feel safe, so they decide to stay.
Likewise people influence each other. They talk about it, the word gets around. Instead of doing and taking things, they come to relax and to observe. They learn to see the underwater world in a different light. They turn a snail to help it right itself again. They touch a fish and are surprised that it touches back. They play with a stingray. They suddenly see that the sunrays play with the kelp fronds. It's been there all along but now they see it. The marine reserve has been most helpful in educating people about marine reserves.
The diver's attitude is changing too. No longer is the success of a dive measured only by the weight of the catchbag but 'just looking' is gaining respect and so is sharing what one has seen. As people become more interested, they want to know more, which in turn increases the pleasure of a dive.
Amateur fishermen are becoming more careful too. More and more they
are fishing for the sheer pleasure of it. It is the game that counts, rather
than the marbles. They tag fish and return it to the sea; they are more
cautious in setting nets and take more care not to lose them; they kill
the fish to put it out of its misery quickly and they have improved their
fishing skills not to lose tackle unnecessarily. But we shouldn't be complacent.
There are still too many things wrong with our present-day reserves.
|Are our marine reserves working?
When one observes the many people visiting the Goat Island marine reserve, swimming in the water amongst the numerous friendly fishes or hand-feeding them, one could easily believe that our marine reserves are unqualified success stories. But let's have a closer look at what has really happened.
Those friendly fishes are not so friendly at all. They form marauding gangs that follow the divers, nipping their fingers and constantly begging for food. The powerful snapper team up with the brainy blue cod to harrass other life: crayfish, octopus, conger eel, moray eel are no longer safe. These have by and large disappeared from around the channel.
It has almost become impossible to find a spot inside the reserve where fish do not behave this way. In other words, to observe fishes in their natural behaviour, one needs to go outside the reserve! The situation is worse than in a zoo where one is not permitted to feed the animals.
On a good summer weekend people feed perhaps as much as a tonne of perishable food, too much to be consumed. It decays along the beach and coves and covers the bottom in a layer of decaying matter, mixed in with the sand. All year long, this layer is easily stirred up by waves and hundreds of little flippers, turning the water murky.
There are so many fishes, sea birds and ducks in the area that their excrement contributes to the muck. People often complain about the murky water, being little aware of their own contribution. Scientists have measured a decrease in the snapper and crayfish population. But this doesn't come as a surprise since longliners and craypotters operate all along the boundary of the reserve which is only 800 metres away.
All the big reef snapper I have known, have disappeared. The really big crayfish are almost impossible to find. So it appears as if the reserve has had a detrimental effect on the life within. How is that possible?
In the time since 1977, fishing has continued outside the reserve to such an extent that only perhaps a few percent of the original crayfish population remains out there. Fishermen fish the boundaries of the reserve so intensively that any crayfish or snapper straying outside the reserve, will be caught. Both snapper and crayfish forage the sandy seabottom outside the reserve for their daily feed, passing the barrage of longlines and craypots.
The reserve is just too small. When this reserve was created, scientists were interested in their experiments on the rocky shore only, little realising at the time that a vast area of sandy and muddy bottom is of economical importance to many a shore animal (feeding grounds). We had never thought that the boundaries would be fished so intensively, all the more reason for a bigger safety margin.
The little blue penguin or fairy penguin breeds in the caves along the reserve and it daily swims 2 - 6 km out to sea to feed. Should its range be protected? The kahawai shoals swim 1-2 km out from the shore, patrolling stretches of 4-10 km. Should they be protected? What about the blue maomao schools that live around Cape Rodney? And so the list goes on, in each instance pointing to the reserve's inadequate size. We know now that it should have been 80 square kilometre rather than four. But to change it now would be very difficult.
We have sold the public a number of benefits arising from marine
reserves: "They serve as seed stock for the rest of the seas".
in all these years we haven't been able to substantiate such. Present
day marine reserves are just too small to have any effect on the
outlying areas. Not only are they too small but they are also ribbon-shaped,
long and narrow, which exacerbates the effect of unexpectedly intensive
fishing on their boundaries. "They serve as a baseline for studying
the sea". The idea is that reserves would eventually revert to pristine
conditions with optimal levels of sea life. Practice is different, however.
reserves are still deteriorating. "We could learn from how reserves
revert to their pristine conditions". But there hasn't been any study
of the progression inside a marine reserve, or the 'baseline' from
which we were supposed to learn. "There will be a network of marine reserves
so that the public has many alternatives". But around the big cities, reserves
with clear water where snorkeling can be enjoyed, are a rarity. In fact,
the seas around a big city like Auckland, are in such a bad state that
it would be doubtful that a reserve there would do any good at all. It
is furthermore impossible to find a second Goat Island, for instance. Some
reserves are bound to attract vast numbers of visitors, whereas others
|Mud, the new scourge
In the past 10-15 years, a new threat has presented itself, increasing alarmingly with every decade. It is the already mentioned threat of run-off from the land. The soil consists of four main components, which differ in their presence for each soil type: humus, sand, silt and clay. When soil erodes, its components are separated and washed into the sea, where the smallest particles (silt and clay) remain suspended longest. The fertility of the soil (nutrients) clings mainly to the humus and soil components, being extracted once it reaches the sea. The nutrients (over) fertilise the plankton, causing often poisonous nuisance blooms. The mud (silt + clay) is suffocating, and darkens the water to the extent that plants can no longer grow where once they could.
My own observations have indicated the following reasons for this sudden problem:
|Whenever we look at the reserves created in the past few years, we can see that the same mistakes have been made over and over again. The time has come to stop and think. Is there a better way? It makes no sense to carry on along the same path, creating one failing reserve after another inside yet another degrading environment. But this is precisely what we are going to do.|
|Towards a better marine conservation
We can treat the sea in various ways, ranging from uncontrolled exploitation to conservation. If we do nothing at all to protect the sea, the past has shown that this results in no less than rape and pillage of the 'commons'. We have become convinced that some sort of regulation is necessary, and that is the level at which our fisheries have arrived. But it can move further, towards a more balanced form of exploitation and towards more caution.
Likewise, our present marine reserves policy has as its ultimate goal a no-take policy that costs us nothing. But it too should go further towards creating some pristine wilderness areas without the defects of present-day marine reserves, areas where the detrimental effects of civilisation will be turned back. These reserves will cost us dearly but they will also be the ones that we will be most proud of, and the ones that will work.
|We think that passive conservation ,'it cost nothing', is the last
word. But we should go further. The Long Bay marine reserve lies in an
area where the water quality deteriorates year by year. It stands to reason
then that ten years from now it will have fewer species and less life than
today. So what's the use of that reserve then?
The proposed Mahurangi reserve suffers a similar fate. Its threat is the deteriorating water quality of the Mahurangi estuary and to a much lesser extent overfishing. Obviously the era of passive conservation has ended. The time has arrived to be pro-active and to say that marine reserves do cost a lot of money and effort. We need to stop the soil washing into the sea. We need to change our farming methods.
We need to plant forests on eroding hillsides and fence these
off. We need to plant forests in the gullies and fence these off. We need
to improve our topsoils and treat these as our main assets, rather
than the sheep and cattle who graze on top. We need to be more proactive
about our sewage treatment and disposal. We need to be more cautious
in our urban developments and in the logging of forests.
|We should not wield the marine reserve concept as a blunt weapon to
solve all our problems because it can't. We could end up with a solution
that will not work and that could antagonise people. We have to be up-front
with what we want to achieve and first of all we must ask ourselves
what the problem is that we want to solve. Then we should look into
our conservation 'toolkit' and use the tools that are most appropriate
for the situation. Often education is all that is needed.
It is equally important to involve the local people because their support is needed most and often they know best how to manage something they are already familiar with.
Once the required conservation measures have been put in place, we must monitor and evaluate the results regularly against the objectives that we wanted to achieve.
We must also recognise that marine reserves do not come in one model only. We can have reserves for a cultural or spiritual purpose, for science, for education, for protecting a threatened species, for protecting a unique spot, for protecting a threatened habitat. Some reserves will indeed allow for limited extraction, much the same as some reserves will be managed exclusively by the local community (kaitiaki).
But we have coasts that do not suffer much from the runoff from the
land. Let's have a look at one of our most fascinating remote reserves.
|The Poor Knights marine
Those who have dived the Knights will have been impressed by the diversity and abundance of life that it supports. It is almost like going overseas. Located at the outer edge of the NZ coastal sea, only about 8 nautical miles from the mainland, it is surrounded by waters that do not or rarely get affected by the runoff from the mainland. The waters are usually clear, except for a spell of plankton bloom in early spring.
Respecting the special nature of these islands, divers have voluntarily declared it a marine reserve, far ahead of the day that it became one officially. This was remarkably effective. But an unwritten rule allowed for the spearing of 'pelagics' and the taking of crayfish. Also the big game fishermen freely caught their 'baitfish' from the many dense schools of trevally and kahawai and insisted on their right to catch big game fish in the area.
So when the reserve became law, these exceptions stayed and made it a half-hearted reserve, because it doesn't give the environment the full protection it deserves (These islands are really very very special). Till 1998 one could fish for pink maomao (even spearfish them), trevally and snapper although a small area had been declared off-limits for all forms of fishing.
I can still remember the day a purse-seiner came in and cleaned up all trevally schools. It took over ten years to recover and I still haven't seen the blunt-nosed oldies back again. With the present rules these exceptional schools that delight many a snorkel diver, are still not protected. The rule to fish with stray (unweighted) lines only, makes sure that the bait cannot sink to the bottom and thus catch reef fishes. But the straying snapper and schooling fish are the ones that get taken. Although crayfish can no longer be taken from the Poor Knights, they may never have been very numerous anyway. It would be interesting to see whether they will return at all because it is quite possible that the level of crayfish recruitment is so low that it may take a very long time indeed.
Apart from these anomalies, the Knights reserve forbids divers to take things such as the rare and coveted Poor Knights cowry (Pacific deer cowry), living well camouflaged in shallow cracks. Also protected from collectors is the spindle cowry, growing in deep water, almost invisibly camouflaged on the soft-pink primnoides gorgoneans (bead corals). More common species such as corals, gorgoneans and other shells now also escape the clutches of collectors.
However, certain spots at the Poor Knights are so popular that the sheer number of divers is causing damage. The delicate growth of sponges and bryozoa on the walls and bottom of Blue Maomao Arch in South Harbour has almost disappeared because of divers scraping along the walls or leaning against them or landing heavily on the bottom rocks. In other archways the vast amount of compressed dive air has caused organisms to fall dry to the air or get damaged by the rushing bubbles. This is perhaps the damage that results unavoidably and inadvertently in the course of enjoying the reserve. Again the places where this has happened are very small compared to the total area that can be visited.
Whereas the Poor Knights were previously visited by very keen New Zealand divers, crowding uncomfortable charter boats, the scene has changed immensely because of the tourist dollar. More and more luxurious charter boats ply foreign tourists to a few popular diving spots that visibly bear all the brunt, and this activity is still growing.
As mentioned, even today one may find spearfishermen operating in certain areas. The reason that I object strongly to this is that they portray man as an ordinary predator rather than a caretaker. They instill fear not only into the individual fish but this fear is then passed on to the school and because schools intermix occasionally, this fear is passed on and on, much like the way land birds are still very shy even though we won't harm them any longer.
So I take great exception to a very few people spoiling the environment for so many, so thoroughly. I have learnt that reserves should be created not half-heartedly but for a hundred percent so that what the fishes encounter under water is mankind as a caretaker. Only then will we get full satisfaction from this new relationship.
(Note! The Poor Knights have now indeed been declared a no-take reserve
and will hopefully reward us in due time)
The way mankind behaves and the extent to which he changes his environment
to suit his own self-centred needs, have been detrimental not only to nature
but also to himself. Fortunately the news is not all that bad and there
are things he can do to positively change the situation for the better.
One of these is to create more and bigger marine reserves in order to preserve
the quality and quantity of marine life. From the marine reserves we now
have, we have learnt that they can work, even though many do not. These
reserves can enrich the seas around us while at the same time providing
a playground for people to enjoy, and a natural laboratory for scientists
to study. What's more, it doesn't cost money to have them. We merely need
to change our attitude and our behaviour. But now the time has come to
put effort and money where it really matters. Mor importantly, we need
to save the land first in order to save our seas. It will be a tremendous
challenge for the new century, but well worth the effort. After all, aren't
we the last green emerald in a turquoise sea?
|DISCUSSION POINTS FOR MARINE
This chapter contains valuable discussion points, suitable for the classroom. One can also retrace the bold printed sentences of this article and the blue boxes with summarised points.
What is conservation?
Who or what causes the threat?