W. J. Ballantine, Leigh Marine Laboratory, New Zealand
Marine reserves have been discussed for many years,
and there are now examples in many countries. We know that they are
practical and that, once established, they are generally popular and
successful. We have carried out enough trials and tests. It is
time to create full systems of marine reserves. To do this we need a
clear policy based on principles that everyone can understand.
1. There are many kinds of marine life (species diversity), these occur in many different habitats and communities, and they interact in many ways. Marine life existed before people became active in the sea, and it maintained itself.
2. This natural marine life is abundant, varied and complex. It occupies 70% of our world. It carries out many processes that are important to the planet. Marine life is far more than a set of things directly useful to people, but we are only dimly aware of how the whole system operates.
3. Despite increasing rates of study, we are still very ignorant about marine life. Less than half the species have been described, few regions have had their habitats mapped, and we only know some examples of the natural processes. We do not know how much of anything is necessary to sustain the whole in a healthy state, but it is clear that the natural processes are critical to all life on the planet.
4. Many human activities in the sea (fishing, dumping, dredging, etc.) can kill or degrade marine life and its habitats. The range and intensity of human-induced damage have increased over the years; have already caused multiple and widespread changes to marine life; and now threaten its sustainability.
5. Our existing ways of planning and managing human activities in the sea are useful and necessary, but they are not sufficient to prevent or adequately control this damage. Existing management mostly tries to solve problems, but the problems (e.g. damage) have to occur and be noticed before action is taken (reactive management).
6. More positive action is also needed. Setting aside areas of the sea (marine reserves) which are protected against all direct human interference will help maintain (or restore) the full natural biological diversity.
7. These marine reserves will have many additional benefits. They will make it easier for people to appreciate and understand natural marine life. They will help us recognise the changes our activities have caused, and distinguish these from natural variation. Marine reserves will help us measure these changes, and show how we could adjust our activities sensibly. Marine reserves are important to science, management, education, and recreation; as well as essential for conservation.
8. Marine reserves are a new, different and additional form of management. They do not aim to solve particular problems, simply to maintain the natural biodiversity. They do not depend on particular information (e.g. identifying damage), all potentially-disturbing activities are excluded on principle. Problem-based, data-dependent planning and management will continue in the rest of the sea.
9. Standard planning will steadily improve. The introduction of zoning is one such improvement. When zoning is adopted in a region, marine reserves will be included as the first and most important zone. Indeed reserves will help lead to this form of management.
10. All these points are universal. They apply everywhere, and are independent of climate, the marine life that occurs, what people are doing to it, or who is in charge. To maintain (or recover) the full natural marine life, marine reserves are needed in all regions. In each region the reserves must form a system which is sufficiently large and comprehensive to be self-sustaining despite human activities in the rest of the sea.
Each region requires a policy which includes the following principles:
The reserves are highly protected. All potentially damaging human
activities are banned on principle, as far as is practical and sensible.
These rules are efficiently enforced.
reserves support all standard marine management, but they are not a
panacea, nor an alternative. Detailed and general management must continue
outside the reserves, and steadily improve. Reserves cannot operate
successfully unless exploitive use outside is kept within reasonable
bounds. In particular, marine reserves do not protect marine life against
damage caused by things that float or flow into the reserves (e.g. water
borne silt or pollutants) or atmospheric changes (e.g. global warming),
but reserves are necessary to distinguish these effects from direct damage
and to measure both.
Dr Bill Ballantine is a marine biologist at the Leigh Marine Laboratory, University of Auckland, New Zealand. He has advocated the concept of no-take marine reserves since the 1960s and helped promote many of the existing reserves in New Zealand waters. This document is an updated version of the paper first published in the April 2003 edition of MPA News (4:9, Scientific Principles for Marine Reserve Systems); republished in MPA News 7:7 February 2006.