8152

• UCREFRP Catalog Number: 8152
• Author: Olver, C. H., B. J. Shuter and C. K. Minns.
• Title: Toward a Definition of Conservation Principles for Fisheries Management.
• USFW Year: 1995.
• USFW - Doc Type: \
• Copyright Material: YES

Perspective

Toward a conservation ethic and a
definition

Neither the Romantic Preservation Ethic nor the Resource
Conservation Ethic provides a viable foundation for a mod-
ern definition of conservation because both represent pre-
ecological views of the environment. The first rejects sci-
entific argument entirely, demanding specific, quasireligious
commitments that are incompatible with the secular and
multifaith societies of today. The second is rooted in a
19th century scientific paradigm that has been superseded
by a deeper understanding of environmental realities
(Callicott 1991). With its evolutionary and ecological basis,
Callicott (1991) argues that Leopold's land ethic "ought
to supplant its 19th century antecedents": it is less con-
strained by the cultural biases that taint the earlier views and
it generates management policies that should be accept-
able to moderates from both sides of the conservation
movement. This ethical position leads to a definition of
conservation that recognizes roles for both wise use and
preservation but adopts neither as its central premise.
This definition can be developed within the context of
current ecological knowledge. Odum (1959) saw conser-
vation in the broadest sense as "probably the most impor-
tant application of ecology" and he considered the prin-
ciple of the ecosystem as "the basic and most important
principle underlying conservation." Current science views
the ecosystem as an integrated collection of abiotic and
biotic entities that interact through exchanges of matter
and energy (Allen and Hoekstra 1992; Pickett et aL 1992).
A major theme is the continuity of ecosystem processes
in the face of significant temporal variation in its abiotic
components (Pickett et aL 1992). This ability to maintain
functional continuity is essential to ecosystem sustain-
ability and has been equated with such desirable qualities
as ecosystem integrity and ecosystem health. Another major
theme is the role of biodiversity in determining the degree
of integration among system components and in supply-
ing the functional redundancy necessary to ensure long-
term system sustainability (Allen et aL 1993). In a con-
servation context, it is important to recognize the distinction
between ecosystem function and ecosystem biodiversity.
As Allen et al. (1993) pointed out, these two qualities
should be treated separately because preservation of ecosys-
tem function is a necessary, but not sufficient, condition
to ensure preservation of biodiversity.
From this ecosystem perspective, conservation should
mandate the safeguarding of healthy life-support systems
that "are the ecological processes that keep the planet fit for
life. They shape climate, cleanse air and water, regulate
water flow, recycle essential elements, create and regenerate
soil, and enable ecosystems to renew themselves" (World
Conservation Union, United Nations Environment Pro-
gramme, and World Wide Fund for Nature 1991). In addi-
tion, conservation should mandate the control of major
stresses (e.g., habitat alteration, exploitation, species intro-
ductions) to mitigate negative effects on ecosystem func-
tion and biodiversity. The goal of conservation should be
healthy ecosystems. This goal is consistent with the land
ethic. It can be achieved by ensuring that native biota are
sustained in harmony with their natural environments.

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A conservation ethic based on ecological values requires that
humans derive social, economic, recreational, and cultural
benefits in a sustainable manner. A definition of conser-
vation consistent with this position follows:

the protection, maintenance, and rehabilitation of
native biota, their habitats, and life-support systems
to ensure ecosystem sustainability and biodiversity.

This definition of conservation does not contain the
terms use or sustainable use. Conservation can no longer
imply just use or advocate use as its central tenet. Con-
servation must clearly warrant the limitation of use to
ensure ecosystem sustainability. In some situations, effec-
tive conservation will demand complete prohibition of use.
This definition is sufficiently broadly based to include
preservation through protection and use through mainte-
nance (e.g., as in maintaining a vehicle that is being used
by periodic servicing). We use the term rehabilitation to
mean "to return a degraded ecosystem or population to an
undegraded condition, which may be different from its
original condition" (World Conservation Union, United
Nations Environment Programme, and World Wide Fund for
Nature 1991).
The definition does not include the terms restoration
("to return a degraded ecosystem or population to its orig-
inal condition") or enhancement ("increasing the capacity
of an ecosystem or population to fulfil a particular function
or yield a specified product") (World Conservation Union,
United Nations Environment Programme, and World Wide
Fund for Nature 1991) because (i) restoration may be dif-
ficult, if not impossible, to achieve in most cases (Francis
et al. 1979; Meffe 1995) and (ii) attempts at rapid alteration
of natural carrying capacities through enhancement activ-
ities such as the stocking of desirable exotic species weak-
ens existing ecosystem structure and function ( Evans et aL
1987). ComIT\Jlnity transformations via species invasions
and deliberate stocking of exotics (vis a vis enhancement)
also make recolonization attempts with native species more
difficult (Evans and Olver 1995). Loftus (1976) recom-
mended that rehabilitation should be the approach used in
Canadian fisheries science; he rejected enhancement, argu-
ing that it was quite a different approach and perhaps even
antagonistic to rehabilitation.
This definition does not preclude the introduction of
exotic species, nor does it require blanket acceptance of
the consequences of unplanned invasions. However, expe-
rience has shown that exotic introductions often have unex-
pected, negative consequences for native ecosystems that
are very difficult to reverse. Thus, we believe such intro-
ductions should be carefully evaluated to ensure protec-
tion of existing native biodiversity.

Conservation principles for fisheries
management

Having offered a definition of conservation, and a ratio-
nale to justify it, we now consider how these ideas can be
applied in a fisheries management context. Our objective
is to develop a set of practical principles that will guide
fisheries managers in their role of maintaining the viability