Ecological management: Concept

ECOLOGICAL MANAGEMENT

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 “ecological management” or “large-scale conservation” has become the mantra of many conservation organizations, both public and private. In broad outline the objectives of ecological 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 (1994) suggests that ecological 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., ecological management is intended to result in both a sustainable system and a set of sustainable management activities.

Groom et al. (2005) suggest a slightly different definition, one that explicitly recognizes the role of social, economic, and institutional factors in ecological management projects:

An approach to maintaining or restoring the composition, structure, and function of natural and modified ecologicals 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 (Figure 5.2).

Before discussing concerns that have been raised about ecological management, let’s outline the steps in the process that might be followed in developing an ecological management plan. According to Harwell (1997), the development of the ecological management plan falls naturally into four distinct phases:

1.    Determining the current status and threats,

2.    Identifying the biologically achievable management goals,

3.    Characterizing societal factors that influence the choice of management goals, and

4.    Establishing management goals.

CURRENT STATUS AND THREATS

Before you can manage a system you have to know what its characteristics are. In the case of an ecosystem that means knowing its current status and the threats it may be facing. That means doing at least two things:

1.    Determining the boundaries of the ecosystem to be managed and the types of habitat within it that are to be managed and

2.    Developing a conceptual model of human influences on the ecosystem.

The threats are manifold, and nearly all are related to human pressures.

BIOLOGICALLY ACHIEVABLE MANAGEMENT GOALS

Once you’ve figured out what the system is that you’re trying to protect and you’ve identified the threats to the system, you have to figure out what endpoints are biologically achievable. To identify what things are possible it is necessary to select appropriate measures for the “health” of various ecological components.

An implicit part of defining biological achievable management goals is that the goals are sustainable for the indefinite future.

SOCIETAL FACTORS

Human and societal influences except to the extent, pose a direct threat to the species. Conservation initiatives may sometimes be needed at a very broad scale, and at that very broad scale humans are almost always part of the system. That means if the system is to be managed sustainably, attention must be given not only to the needs of non-human organisms in the system but to those of humans as well.

There are three different ways in which it is necessary to assess societal factors.

1.    The human activities that lead to substantial influences on or domination of ecosystems must be identified and understood.

2.    The legal, economic, institutional, political, and other societal factors that affect the frequency and scale of those activities must identified and understood.

3.    The values and preferences of relevant interest groups with an influence on the ecosystem must be characterized.

The last of these items may be the most difficult for many environmentalists to accept. The list of biologically achievable management goals is likely to include a range of options from those where large portions of the ecosystem are substantially free of human influence to those where large portions of the ecosystem are human-dominated or human-influenced.

ESTABLISHING MANAGEMENT GOALS

With all of that in place, all that is necessary is to “establish ecological sustainability goals in terms of ecological endpoints and human values.”

If you are a biologist participating in such a process, your expertise will be particularly important in defining what endpoints are achievable. While biological expertise is needed to define the range of the possible, choosing among possible endpoints is a question of values.

Biologists have no special competence on this choosing among competing values. We can describe the consequences of different choices, but we don’t necessarily have any special standing to choose one set of consequences over another. In a discussion about choosing among endpoints, what biologists can do is to make sure that everyone discusses only scenarios that can be achieved and that everyone understands the tradeoffs among them.

As Harwell et al. (1999) point out, decisions about design and implementation of an ecological management program lie along a continuum:

1.    Societal values will have a dominant role in determining the outcome of those that are predominantly concerned with defining the management goals.

2.    Scientific expertise will have a dominant role in determining the outcome of those that are predominantly concerned with measuring how the system responds.

3.     Societal values and scientific expertise will have equal roles in determining the system endpoints that will be measured to determine whether management goals are being achieved.

ADAPTIVE MANAGEMENT

Adaptive management is simply the idea that management actions are like experiments. They are tests of hypotheses about how the system works. So if we monitor the results of those tests, we can confirm or reject our hypotheses and improve our understanding of the system while we manage it. We do not have to wait until all of the answers are in. We can gather some of them while we proceed.

A CRITIQUE OF ECOLOGICAL MANAGEMENT

Goldstein (1999) argues that the ecological management not only often fails to honor those principles, but also that it is largely an attempt to bypass the requirement for life history information on all species of concern. He goes on to argue that this attempt is doomed to failure for three reasons:

1.    Measures of local species richness can diminish the contribution of threatened species to priority setting.

2.    Good “indicator taxa” don’t exist, i.e., it’s not possible accurately to predict community properties from the presence or absence of certain taxa.

3.    Concepts like ecological integrity, ecosystem function, ecosystem resilience, ecosystem health, and naturalness don’t provide concrete guidelines for management.

His objection boils down to this:

For management strategies and techniques to be successful at preserving anything other than perceived structures, functions, and processes of landscapes, they must be evaluated against the performance of populations and metapopulations in those managed landscapes, including but not limited to the most sensitive and threatened species . . . ecological management will be successful only if ecosystem is used in a sense that can be guaged with precision and if the criteria used actually reflect the needs of natural entitites we wish to protect rather than abstracted emergent properties, functions, and processes of groups of organisms.