Introduction

The enormous scale of the extinction crisis we are now facing poses daunting challenges. The number of species threatened with extinction is so vast that it is virtually impossible to imagine that more than a few of the most important individual species will receive detailed study. It would seem that our most realistic hope for preventing extinction on a massive scale is to manage entire systems to conserve their biodiversity. The idea is that we should manage an ecosystem and its processes in a way that will protect its structure. Our hope is that by doing so we will also protect the populations of most or all species that are part of that ecosystem.

In the last ten or fifteen years ``ecosystem management'' or ``large-scale conservation'' has become the mantra of many conservation organizations, both public and private. In broad outline the objectives of ecosystem management seem clear and unobjectionable:

To maintain hierarchical patterns of biological diversity as well as the processes and functions supporting the phenomena that spawned them.

Grumbine [3] suggests that ecosystem management is based on three observations:

1. To protect biological diversity the processes that produced it must be protected as well.

2. Species richness alone is not a good measure of management success.

3. Management must be planned for the long-term, possibly even for the indefinite future, i.e., ecosystem management is intended to result in both a sustainable system and a set of sustainable management activities.

Groom et al. [2, p. 468] suggest a slightly different definition, one that explicitly recognizes the role of social, economic, and institutional factors in ecosystem management projects:

An approach to maintaining or restoring the composition, structure, and function of natural and modified ecosystems for the goal of long-term ecological and human sustainability. It is based on a collaboratively developed vision of desired future conditions that integrates ecological, socioeconomic, and institutional perspectives, applied within a geographic framework defined primarily by natural ecological boundaries (see Figure 1).

Figure 1: One way of envisioning the conceptual basis of ecosystem management (from [2]).

Before discussing concerns that have been raised about ecosystem management, let's outline the steps in the process that might be followed in developing an ecosystem management plan by looking at a particularly well-developed example: the ecosystem management schemes developed for south Florida [4].