Ecologically based fisheries management:
assessment benchmarks.
Jon Nevill 5 July 2008.
The place of ecologically based fisheries management (the ‘ecosystem approach’) within the development of fishery industry paradigms has been discussed in an earlier chapter. The purpose of the present discussion is to provide a brief overview of ecologically based fisheries management (EBFM)[1], to identify the essential elements of the approach applicable to practical fishery management from a literature review, and to use these elements to formulate testable EBFM benchmarks by which an agency program can be judged.
Fundamental concepts:
The ecosystem approach grew from the disciples of ecology and conservation biology, combined with a little management theory. The word ecology is derived from the Greek oikos, meaning ‘house’ or ‘place to live’, and logos ‘knowledge’. Literally, ecology is the study of organisms ‘at home’. A Webster’s Dictionary definition is “the study of the totality or pattern of relations between organisms and their environment”. The term (oekologie) was first used by the German biologist Ernst Haeckel in 1866; however the first significant textbook on the subject, and the first university course, was written by the Danish botanist Eugenius Warming in 1909 (Wikipedia 22/6/08). While Warming is often identified as the founder of ecology, the science owes much to important figures in the mid-twentieth century, such as Eugene Odum. Odum’s major textbook ‘Fundamentals of Ecology’ is still in use today (Odum 1971). Odum defined an ecosystem as:
a unit that includes all of the organisms (ie: the "community") in a given area interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (ie: exchange of materials between living and nonliving parts) within the system.
This definition of an ecosystem raises an immediate issue which is important in all attempts at ecosystem management: where does an ecosystem start and end? Even in situations which seem to provide distinct natural boundaries, such as a catchment, lake or estuary, there are clearly flows of organisms and materials which cross these boundaries. Within extended coastal waters, bioregions may be defined containing repeating patterns of similar ecossytems (Commonwealth of Australia 2005). Ken Sherman has been instrumental in promoting the concept of ‘large marine ecosystems’ spatially defined by ocean basin topography, currents, upwellings and fronts (Sherman & Alexander 1986). Despite the shortcomings of the ‘ecosystem’ concept, it has proved of great use to scientists and managers, and provides the foundation for ecosystem based fisheries management.
Ecosystem based management:
Ecosystem based management, although in use in one form or another for the best part of a century, remains an evolving concept. Grumbine’s seminal essay (Grumbine 1994) provides important historical perspective. The Ecological Society of America actively promoted important elements of the ecosystem approach from the early 1930s. People such as Aldo Leopold were influential in promoting and popularising the concept in the 1940s. “By the late 1980s an ecosystem approach to land management was being supported by many scientists, managers and others” (Grumbine 1994:28).
Importantly, the concept appeared for the first time in a major international agreement – and related to marine management – in 1980. The Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR) Article II(3) defined three “principles of conservation”, of which the second and third principles identify the need for harvesting management to (a) protect entire ecosystems, and (b) take a cautious approach to ecological risk, particularly with regard to irreversible effects. The boundaries of the Convention were – appropriately – defined by the approximate location of the Antarctic Polar Front (otherwise known as the Antarctic Convergence, at about 500 south) which provides a rough natural boundary for the Antarctic large marine ecosystem.
Grumbine’s 1994 paper is important for a number of reasons, not least of which is his thoughtful discussion of the social and governance implications of the ecosystem approach. He suggested a definition:
Ecosystem management integrates scientific knowledge of ecological relationships within a complex socio-political and values framework toward the general goal of protecting native ecosystem integrity over the long term (Grumbine 1994:31).
Grumbine identified five ‘ecosystem management goals’ which, he pointed out, “provide a striking contrast to the goals of traditional resource management” (Grumbine 1994:31). These are to:
· maintain viable populations of all native species in situ;
· represent, within protected areas, all native ecosystem types across their natural range of variation;
· maintain evolutionary and ecological processes;
· manage over periods of time long enough to maintain the evolutionary potential of species and ecosystems; and
· accommodate human use and occupancy with these constraints.
Grumbine’s extensive literature survey included few marine examples of either advocacy or implementation of the ecosystem approach. His finding that the perspectives of the US Forest Service (on the subject of the ecosystem approach) were narrow and production-oriented may perhaps come as no surprise. A similar finding might be expected in comparing the perspectives of fisheries management agencies with those of academic ecologists – or indeed the public at large. Grumbine found: “… in the academic and popular literature there is general agreement that maintaining ecosystem integrity should take precedence over any other management goal” (1994:32). This concept has been echoed in policy formulation down the years. Pikitch et al. (2004:346) echo this idea with respect to fisheries when they advocate exploitation “without compromising the ecosystem.” Australia’s Oceans Policy (1998:19) states: “…priority should be given to maintaining ecosystem health and integrity”. The reality of fisheries management, however, often runs directly counter to such clear statements of policy intent.
Grumbine explored the long-term implications of the ecosystem approach in the context of changing social values and institutions. He argued (1994:34) that the comprehensive application of the ecosystem approach will “not only help reduce our negative impact on the biosphere, but will also give us the opportunity to reinterpret our place on the planet as one species amongst many. Protecting ecological integrity becomes the ultimate test of whether people will learn to fit in with nature. Thus, ecosystem management gains importance far beyond finding new ways to manage parks and forests” – and, I would add, oceans. This observation of the ethical importance of the ecosystem approach should not be lost sight of, and, I believe, is as critical for ocean ecosystems as it is for those of terrestrial and freshwater environments. Ethical issues are addressed in more detail in an early chapter of this thesis.
Ecosystem based fisheries management:
Grumbine provided a historical overview and a status report of the concept of ecosystem based management as it had evolved to 1994. Since then (and especially since 2000) a number of publications have appeared dealing specifically with the application of the concept to fisheries management. Moreover, growing public awareness of the biodiversity crisis, and the likely negative impacts of climate change on what remains of the natural world, has prompted the endorsement of the ecosystem approach in important international and national policy statements. A brief summary follows (for details see the earlier chapter on international agreements).
At the international level, the Convention on Biological Diversity 1992 (CBD), through the related Jakarta Mandate[2], explicitly promotes the application of the ecosystem approach to the marine environment. The FAO Code of Conduct for Responsible Fisheries 1995, although not mentioning the ecosystem approach by name, does require complying nations to adopt several key elements of the approach[3] (see Table 1 below – note that implementation of the Code’s provisions is voluntary for endorsing nations). The Implementation Plan of the World Summit on Sustainable Development 2002 requested endorsing nations to implement the ecosystem approach to fisheries management by 2010. Each year the United Nations General Assembly (UNGA) meets to consider pressing global issues. For the last several years, the twin UNGA resolutions dealing with fisheries, and with the Law of the Sea, have endorsed the ecosystem approach, and urged its rapid implementation. Australia has ratified the CBD, supports the FAO Code of Conduct, the WSSD Implementation Plan, and has supported all recent UNGA fisheries resolutions.
International endorsement of the ecosystem approach is reflected in core Australian national policy. The National Strategy for the Conservation of Australia’s Biological Diversity (Commonwealth of Australian 1996) requires the implementation of the ecosystem approach, including within fisheries management. All Australian jurisdictions endorsed this Strategy. Australia’s Oceans Policy 1998 (Commonwealth of Australia 1998) did not receive the same wide jurisdictional endorsement; nevertheless it too requires the implementation of the ecosystem approach to oceans management. The concept of ecosystem management lies behind the regional planning approach promoted by the Oceans Policy, where the planning boundaries coincide, as far as practical, with the boundaries of identified (provisional) Australian marine bioregions.
Within these documents, and within academic papers which seek to clarify, elaborate and define ecosystem based fisheries management, key themes emerge. Overall, these themes are not unlike the themes Grumbine identified in 1994 – as you might expect. They do, however, add detail important in defining the way the approach may be applied to the marine environment. These themes are listed in Table 1 below, tabulated with the references of my literature review. Note that reference codes in bold refer to documents which deal specifically with EBFM or EBM.
As with EBM, choosing a definition for EBFM from amongst the many available is a matter of personal preference. A simple statement of purpose is useful: the overall objective of ecosystem based fishery management is to maintain and restore healthy ecosystems, and the fisheries they support (after Pikitch et al. 2004:346).
Literature review: what defines EBFM?
Major reviews of EBFM have been published over the last few years. The two theme sections in Marine Ecology Progress Series (Browman et al. 2004, 2005) contain the views of over 40 senior marine scientists. An important paper published in Science by Pikitch et al. (2004) contains the views of 17 senior marine scientists. Major organizations have published reviews, such as the FAO EBFM guidelines (Garcia et al. 2003), the review by the Secretariat to the Convention on Biological Diversity (CBD-ES 2000), as well as the review by the Ecosystem Approach Task Force (EATF 2003). The United Nations General Assembly has also considered the ecosystem approach in a number of its recent reviews (see especially UNGA 2006 A/61/105,156). The American Association for the Advancement of Science has published a major consensus statement (AAAS 2005). Several important papers on the subject have appeared in the scientific literature, as well as reviews sponsored by NGOs (eg: Cripps et al. 2001) and by governments (eg Ward & Hegerl 2003).
I believe I have included all major papers dealing with EBFM published since 2000, however my literature review is not comprehensive, as several minor papers (eg Vierros et al. 2006) have been omitted due to time constraints.
Broadly, the papers selected fall into two groups: (a) those focussed on EBM or EBFM, and (b) more general papers containing substantive discussion of EBFM. There are 18 references in the first category and 10 in the second. Most were published in the period 2000 to 2008.
The papers were searched for themes stated by the authors as characteristic of EBFM. Forty themes were found, as set out in Table 1. The associated references are listed in Table 2.
Of these themes, 18 deal with ‘good governance’, ten with ‘ecological processes’, six with ecosystem structure, four with evolutionary processes, and two with ocean zoning. If these themes characterise EBFM, a definition drawn from them might read:
Ecological based fisheries management is management based on a variety of modern good governance principles and approaches (including ocean zoning), aimed at rebuilding and maintaining the health of ecosystems and their dependent fisheries, principally through safeguarding ecological and evolutionary processes, and ecosystem structure.
A glance at the ‘good governance’ themes (Table 2) shows that many of these themes are governance approaches which have evolved separately from ecosystem based management. Of the eighteen themes, ten are very broad, containing no reference to fisheries, oceans, or even ecosystems – they are simply drawn from modern governance approaches. In my view, the ‘larger’ of these themes, such as the precautionary and adaptive approaches, are in fact best discussed quite separately from EBFM, as they are complex and important approaches in their own right. While I do not agree with their inclusion in a characterization of EBFM, my view is clearly out of favour: the precautionary approach is one of the most commonly listed characteristics of EBFM, with adaptive management not far behind (Table 1).
Of the twenty-four themes which are strongly related to ecosystems (theme groups A, B and C, as well as D7, and D10-12 in Table 1) some are fairly general (eg: A9, protect from pollution). Such themes are probably of little use in developing EBFM benchmarks – all agencies or national governments apply pollution control in one form or another. However other themes are more specific. The themes of ‘protect habitat’ or ‘report ecosystem indicators’ seem potentially more useful in attempts to assess the extent to which a fishery agency is actually implementing EBFM.
The issue of developing indicators and reference points from explicit ecosystem objectives is discussed in a number of papers. Gislanson et al. (2000:471) suggest that ecosystem objectives should include:
· maintenance of ecosystem diversity;
· maintenance of species diversity;
· maintenance of genetic variability within species;
· maintenance of directly impacted species;
· maintenance of ecologically dependent species;
· maintenance of trophic level balance.
Once objectives have been chosen, indicators and reference points can be selected for the six potential ecosystem objectives. Gislanson et al. (2000:471) comment: “There is a need to reconstruct our image of historical conditions of marine ecosystems in a scientific manner, in order to define accurate reference points.” They suggest:
Table 3. Examples of ecosystem objectives, indicators and reference points for ocean zones
Objective / Indicator / Reference pointMaintenance of:
Ecosystem diversity
Species diversity / Areas of shelf disturbed by fishing.
Abundance of species at risk.
Area of distribution. / % of each habitat type undisturbed.
Maximum annual bycatch.
% of distribution area relative to period of moderate abundance.
Species genetic variability / Number of spawning populations.
Selection differentials. / % reduction in spawning areas.
Minimum selection differential.
Directly impacted species / Fishing mortality.
Spawning stock biomass.
Area of distribution. / F0.1
Minimum stock biomass for safeguarding recruitment and forage.
% of distribution area relative to period of moderate abundance.
Ecologically dependent
spp. / Abundance of predator.
Condition of predator.
% of prey species in predator diet. / Minimum predator abundance.
Minimum predator condition.
Minimum % in predator diet.
Trophic level balance / Slope of size spectrum.
Pauly’s FIB index (Pauly et al. 2000).
Aggregate annual removals for each trophic level. / Minimum slope.
Minimum Fishery Is Balanced index.
Maximum % removals.
Source: Gislanson et al. (2000:471)