The word biodiversity is difficult to grasp, because it covers a vast store of thought and knowledge. Should you wish to equip yourself with this knowledge, read Seafriends/conservation/biodiversity. A rough idea of biodiversity is all species, including plants, bacteria, viruses, pests, diseases and so on. Since the only thing a marine reserve does, is to stop fishing, a marine reserve makes a difference only to those species that are fished.

protecting a unique spot: some places in the sea, such as around offshore islands, are hot spots of biodiversity surrounded by a much poorer sea and sea bottom. Islands attract fish towards their shallows. They work like oases, attracting life from far around, including sea birds and sea mammals. protecting scientific experiments: scientists need to be assured that over time, the equipment and cages in the sea remain undisturbed, also the species and individuals that they are studying.

Yes, scientific research has shown in many experiments, that the fish stock inside a closed area recovers (only where these were fished before). Fish become more numerous and bigger. It benefits particularly the large predators. Most studies report an increase of about 2-3 times to what is found outside. However, this affects only the exploited species. The thousands of other species remain unaffected, except that they may be more likely to be eaten by the larger predators.

In 2004, scientists completed a study on the permanent de-facto marine reserve around the Cape Canaveral rocket launch site. They tagged fish inside and outside the reserve and followed their movements. To everyone's surprise, fish inside stayed inside but those outside migrated into the reserve, never to leave. Inside the reserve, the tagged fish were lost, presumably due to predation. The scientists concluded that the marine reserve acted as a sink (like a bottomless pit) to fish.

Protagonists of marine reserves, claim that marine reserves do help fisheries in many ways, but this is not so, or at least very much less than is claimed. It is a hotly debated issue that has been dissected in detail in Seafriends/conservation/marine, but some of the main reasons are easily understood: Our main commercial fisheries occur over the continental shelves where the main food source originates from plankton.

Protagonists claim that we need networks of marine reserves. What they don't say is that they want to establish a fisheries management regime which is not controlled by fishermen but by ideologically driven conservationists, often those who do not relate to the sea, and have no practical experience with it. The network idea sounds plausible and feels good, so let's check it out.

This seemingly simple question is surprisingly difficult to answer. In first instance, one would say that it neither harms nor benefits the environment or people. If there exists no threat, it means that few people are fishing it. But more importantly: what is the point? Are we willing to sacrifice freedom that easily? A father can suddenly no longer take his son fishing from the bridge or wharf. Marooned seamen cannot fish for life without trespassing the law.

Right in the middle of the busiest centres, one can find parks with flowers, and nobody picks them. These are a kind of voluntary reserves, appreciated and respected by all. Likewise, marine reserves right on many people's doorstep, would be appreciated by many and used intensively. However, they need to have clear water, and this is usually not the case near big cities. Wellington is an exception, being located along a coast with swift currents of clear water.

Protagonists for marine reserves have influenced the United Nations to accept a biodiversity strategy (to which New Zealand is signatory), which compels countries to implement marine reserve networks of representative areas, and the Labour Government has made it official policy to have 10% of our seas in marine reserves by 2010 (some say this includes MPAs, which include de-facto marine reserves and Mataitai).

One would expect that before rushing into more marine reserves, our existing marine reserves would have been evaluated first regarding their effectiveness in achieving the expectations we have. But this has not been done. The situation is in fact quite disappointing. In order to achieve political objectives (marine reserves work), DoC has funded research into counting migrant species like snapper, blue cod and crayfish with a questionable method (the baited camera).

A very important aspect often overlooked by protagonists, is that marine reserves do not fix the causes of the problems in the sea. They change neither our behaviour nor our methods. They act like plasters here and there covering small parts of a large wound.

Most of the marine reserves in the world have indeed failed. 69% do not achieve their objectives (Kelleher et al 1995). The Goat Island marine reserve is hailed internationally as the best success story, mentioned in one breath with the Galapagos Islands. This is only so because ambassadors for marine conservation have travelled the world with good-news propaganda, while hiding the real facts (see below and read Lessons from Leigh).

We should not have marine reserves for the sake of having them. It is not about quantity but about quality. Marine reserves are of no use at all, unless they work and achieve their objectives. Such objectives do not necessary need to be environmental. A marine laboratory needs an area to do research. Schools need undisturbed places to do rocky shore and soft shore studies. Migratory sea birds need relays to feed and regain strength.

Scientists claim that they do. A marine reserve protects their experiments. But they need permission from reserve managers in order to do such experiments, even when no harm is done. Scientists need to be able to harvest organisms to study them in the lab. Thes are killed while being dissected. So scientists are not completely at ease with no-take regulations. They complain about the time it takes to obtain permission. Sometimes a research must be done quickly in response to an external event.

Back in the 1960/70s, scientists were suspicious of the Ministry of Agriculture and Fisheries (MAF) because of the many failing fisheries at the time. What they wanted was the security of law for a protected area for scientific research. Thus the Marine Reserves Act 1971 was born. What they did not sufficiently consider, was its unnecessary complexity, due to duplication and linkage with other acts, and enforcement.

A vast amount of literature exists on how reserves should be managed. The following principles apply: If a local resource is involved, local management is to be preferred. This can work only when the management budget is managed locally as well. If a resource is not local (e.g. migrating fish stocks), or the resource is of national importance, central control is to be preferred. For all other resources, some form of co-management achieves best result and compliance.

Seafriends is the most committed group fighting to save our seas. The first Marine Conservation and Education Centre was established in Leigh in 1990, starting its work in 1992. We saw how the sea suffered and how rapidly this became worse, far earlier than anyone else. We then set out to find answers that nobody could give us. In the process, we created an environmental learning resource on the Web, second to none, and the fight continues.

There exists great confusion worldwide as to what biodiversity and habitats are, as these ideas live mainly in our minds rather than out there in nature. Biodiversity is the 'confusion' of life, created in response to external factors. Change the factors, and life's biodiversity adapts likewise. So biodiversity is not a constant thing. Where humans change habitats, wildlife adapts, and remember that in the sea very little habitat change has happened.

When one area is closed, it increases the fishing pressure on the remaining area because the same number of fishermen have to make do with a smaller area and fewer fish. The question is whether the overall pressure (on closed + remaining area) reduces. Protagonists claim this is so, because: Fish spill over from the reserve. So, fishing at the reserve's boundary (fishing the line) is going to make up for the lost area. However, international scientific research has not confirmed this.

By providing sample areas of pristine stock, fisheries managers can assess the level of the stock in relation to a full-baseline. Their target is to fish at Maximum Sustainable Yield (MSY), which is dangerously close to Unsustainable Yield. However, this implies very large reserves, designed with minimal connectivity, while they should also be allowed to be fished for stock sampling.