Concepts and issues in marine ecosystem management
Tóm tắt
Ecosystem management means different things to different people, but the underlying concept is similar to that of the long-standing ethic of conservation. Current interest in marine ecosystem management stems from concerns about overexploitation of world fisheries and the perceived need for broader perspectives in fisheries management. A central scientific question is whether the effects of harvesting (top down) or changes in the physical environment (bottom up) are responsible for major changes in abundance. Historically, ecology, fisheries biology, oceanography, fisheries management and the fishing industry have gone somewhat separate ways. Since the 1980s, increasing attention has been given to multispecies aspects of fisheries, the linkages between oceanography and fish abundance and more holistic approaches to fisheries management. Sorting out the causes and effects of fluctuations in fish abundance is complicated by the lack of reliability of fisheries statistics. Discards, dishonesty and the inherent logistic difficulties of collecting statistics all combine to confuse interpretation. The overcapacity of fishing fleets and their unrestricted use are widely recognized as a contributing cause to overfishing and declines in fish stocks in many parts of the world. Ecosystem management, as shorthand for more holistic approaches to resource management, is, from a fisheries management perspective, centred on multispecies interactions in the context of a variable physical and chemical environment. Broader perspectives include social, economic and political elements which are best considered pragmatically as a part of the context of fisheries management. Objectives in marine ecosystem management are varied. From a biological perspective, an underlying principle of management is commonly assumed to be a sustained yield of products for human consumption. Whether that should be taken to mean that the yield should always be of the same products is less certain. Fishing commonly changes the relative abundance of species of fishes. Thus, a biological objective should specify the species mix that is desired. Concern for the maintenance of global diversity has generated a substantial literature on threatened and endangered species. In general, it has not been considered likely that marine fish species could be rendered extinct and greatest attention has been given to marine mammals, sea birds and sea turtles. The provision of marine parks and sanctuary areas are obvious first steps in providing a measure of protection, at least for the less widely ranging species. Related to the current concepts of ecosystem management are expressions such as ecosystem health and ecosystem integrity which are given a wide range of different meanings, none of which are readily translated into operational language for resource management. These and similar expressions are best assessed as rhetorical devices. The essential components of ecosystem management are sustainable yield, maintenance of biodiversity and protection from the effects of pollution and habitat degradation. Theory for marine ecosystem management has a long history in fisheries and ecological literature. Ecological models such as Lotka-Volterra equations, ECOPATH, trophic cascades and chaos theory do not give practical guidance for management. Fleet interaction and multispecies virtual population analysis models hold more promise for fisheries managers. Alaska provides particular opportunities for developing new concepts in fisheries management. Statistics of catch are good, stock assessments are at the state-of-the-art level and management has been prudent. Debate is active on the causes of substantial changes in abundance of many species including marine mammals, because substantial changes in the fisheries have been accompanied by major changes in oceanographic conditions. As elsewhere, the resultant changes may be a consequence of top-down and bottom-up effects. The bottom part is beyond human control, and ecosystem management is centred on managing the top-down or fisheries component in the context of special measures of protection for particular species. Whether that is a realistic goal depends in part on how much special protection is to be afforded to which species. Marine mammals, for example, are given high priority for special protection, but like fisheries they too may have significant roles in shaping the structure of marine ecosystems. Eventually, ecosystem management must come to grips with the question of how much protection of particular species is desirable in achieving optimal use of living marine resources.
Tài liệu tham khảo
ACMRR (1979) Interim Report of the ACMRR working party on the scientific basis for determining management measures. Rome 6–13 December, 1978. FAO Fish. Circ. No. 718. 112 pp.
Alexander, L.M. (1993) Regional approach to large marine ecosystems. In Sherman, K., Alexander, L.M. and Gold, B.D., eds. Large Marine Ecosystems V: Stress, Mitigation and Sustainability. Washington, DC: AAAs Press, pp. 225–6.
Alverson, D.L. and Larkin, P.A. (1993) Fisheries: fisheries science and management: century 21. In Vorgtlander, C.W., ed. Proc. World Fisheries Congress, Athens, Greece, May 3–8, 1992. New Delhi: Oxford & I.B.H., pp. 150–67.
Alverson, D.L., Freeberg, M.H., Murawski, S.A. and Pope, J.G. (1994) A global assessment of fisheries bycatch and discards. FAO Fish. tech. Pap. No. 339. 233 pp.
Andersen, K.P. and Ursin, E. (1977) A multispecies extension to the Beverton and Holt theory of fishing, with accounts of phosphorus circulation and primary production. Meddr Kommn Danm. Fisk.-og Havunders. (N.S.) 7, 319–435.
Apollonio, S. (1994) The use of ecosystem characteristics in fisheries management. Rev. Fish. Sci. 2, 157–80.
Austen, D.J., Bayley, P.B. and Menzel, B.W. (1994) Importance of the guild concept to fisheries research and management. Fisheries 19(6), 12–19.
Bakuzis, E.V. (1969) Forestry viewed in an ecosystem perspective. In Van Dyne, G.M., ed. The Ecosystem Concept in Natural Resource Management. New York: Academic Press, pp. 189–258.
Bax, N.J. (1991) A comparison of the fish biomass flow to fish, fisheries and mammals in six marine ecosystems. ICES mar. Sci. Symp. 193, 217–24.
Beamish, R.J. (1993) Climate and exceptional fish production off the West coast of North America. Can. J. Fish. aquat. Sci. 50, 2270–91.
Beamish, R.J. and Bouillon, D.R. (1993) Pacific salmon trends in relation to climate. Can. J. Fish. aquat. Sci. 50, 1002–16.
Belsky, M.H. (1993) Legal requirements for management of large marine ecosystems and their component resources. In Sherman, K., Alexander, L.M. and Gold, B.D., eds. Large Marine Ecosystems V: Stress, Mitigation and Sustainability. Washington, DC: AAAs Press, pp. 227–36.
Beverton, R.J.H. and Holt, S.J. (1957) On the Dynamics of Exploited Fish Populations (Min. Ag. Fish. Food, Fishery Investigations, Series II, Vol. XIX). London: HM Stationery Office. 533 pp.
Bocking, S. (1994) Visions of nature and society, a history of the ecosystem concept. Alternatives 20(3), 12–16.
Bohnsack, J.A. (1994) Marine reserves: they enhance fisheries, reduce conflicts, and protect resources. NAGA, the ICLARM Quarterly (July), 4–7.
Boyle, R.N., Sinclair, A.F. and Hurley, P.C.F. (1991) A bioeconomic model of an age-structured groundfish resource exploited by a multi-gear fishing fleet. ICES mar. Sci. Symp. 193, 264–74.
Brugge, W.J. and Holden, M.J. (1991) Multispecies management: a manager's point of view. ICES mar. Sci. Symp. 193, 353–8.
Caddy, J.F. (1993) The age structure of fishing fleets and its relevance for reconstructing past fishery trends and forecasting. In Kruse, G., Eggers, D.M., Marasco, R.J., Pautzke, C. and Quinn, T.J. II eds. Management Strategies for Exploited Fish Populations. Fairbanks: University of Alaska, Alaska Sea Grant College Program Report 93–02, pp. 475–92.
Callicott, J.B. (1995) A review of some problems with the concept of ecosystem health. Ecosystem Health 1(2), 101–12.
Carpenter, S.R. and Kitchell, J.F. (1993) The Trophic Cascade in Lakes. Cambridge: Cambridge Univ. Press. 385 pp.
Carpenter, S.R., Kitchell, J.F. and Hodgson, J.R. (1985) Cascading trophic interactions and lake productivity. Bioscience 35, 634–9.
Christensen, V. and Pauly, D. (1992) ECOPATH II — A system for balancing steady-state ecosystem models and calculating network characteristics. Ecol. Modelling 61, 169–85.
Christensen, V. and Pauly, D. (eds) (1993a). Trophic Models of Aquatic Ecosystems (ICLARM Conf. Proc. 26). Manila: ICLARM.
Christensen, V. and Pauly, D. (1993b) Flow characteristics of aquatic ecosystems. In Christensen, V. and Pauly, D. eds. Trophic Models of Aquatic Ecosystems (ICLARM Conf. Proc. 26). Manila: ICLARM, pp. 338–52.
Christensen, V. and Pauly, D. (1993c). On steady-state modelling of ecosystems. In Christensen, V. and Pauly, D. eds. Trophic Models of Aquatic Ecosystems (ICLARM Conf. Proc. 26). Manila: ICLARM, pp. 14–28.
Christy, F. and Scott, A.D. (1965) The Commonwealth in Ocean Fisheries: Some Problems of Growth and Economic Allocation. Baltimore, MD: Johns Hopkins University Press. 281 pp.
Clark, C.W. (1974) Mathematical Bioeconomics: The Optimal Management of Marine Resources. New York: John Wiley and Sons. 352 pp.
Collie, J.S. and Spencer, P.D. (1993) Management strategies for fish populations subject to long-term environmental variability and depensatory predation. In Kruse, G., Eggers, D.M., Marasco, R.J., Pautzke, C. and Quinn, T.J. II, eds. Management Strategies for Exploited Fish Populations. Fairbanks: University of Alaska, Alaska Sea Grant College Program Report 93–02, pp. 629–50.
Conn, W.D. and Rich. R.C. (1992) Communicating about ecosystem risks. Adv. mod. env. Toxicol. 20, 1–8.
Copland, J.W. and Lucas, J.S. (1988) Giant Clams in Asia and the Pacific (ACIAR Monograph No. 9). Burwood, Australia: Crafterman. 274 pp.
Costanza, R., Norton, B.G. and Haskell, B.D. (eds) (1992) Ecosystem Health: New Goals for Environmental Management. Island Press.
Cushing, D.H. and Walsh J.J. (1976) The Ecology of the Seas. London: Blackwell. 467 pp.
Doi, T. (1962) [On the predatory and competitive relationships among fishes caught in the waters adjacent to Japan]. Bull. Tokai Regional Fish. Res. Lab. 32, 49–118 [Transl. Fish. Res. Bd. Canada No. 461].
Doubleday, W.G. (1976) Environmental fluctuations and fisheries management. Int. Comm. Northw. Atlant. Fish. Sel. Pap. 1, 141–50.
Fasham, M.J.R. (1984) Flows of Energy and Materials in Marine Ecosystems. London: Plenum.
Gee, H. (1995) American ecology at the crossroads. Nature 375, 461.
Glowka, L., Buchenne-Guilmin, F. and Synge, H., in collaboration with McNeely, J.A. and Gündling, L. (1994) A Guide to the Convention on Biological Diversity. (Environmental Policy and Law Paper No. 30) IUCN. 192 pp.
Grumbine, R.E. (1994) What is ecosystem management? Conserv. Biol. 8, 27–38.
Gulland, J.A. (1974) The Management of Marine Fisheries. Seattle: University of Washington Press. 198 pp.
Harden Jones, F.R. (1994) Fisheries Ecologically Sustainable Development: Terms and Concepts. Hobart, Tasmania: IASOS, University of Tasmania. 205 pp.
Hoffman, J.K. (1994) Ecosystem Charter a vision for the future. Great Lakes Commission Semi-Annual Meeting Highlights, p. 2.
Holling, C.S. (ed.) (1978) Adaptive Environmental Assessment and Management. New York: John Wiley & Sons. 363 pp.
Huntsman, G.R. (1994) Endangered marine finfish: neglected resources or beasts of fiction? Fisheries 19(7), 8–15.
Il'inskii, E.N. (1991) Long-term changes in the composition of bottom fish catches on the continental slope in the western part of the Bering Sea, along the Pacific seaboard of Kamchatka and the Kurils. Voprosy ikhtiologii 31(1), 73–81.
Jones, R. (1982) Ecosystems, food chains and fish yields. In Pauly, D. and Murphy, G.I., eds. Theory and Management of Tropical Fisheries (ICLARM Conf. Proc. 9). Manila: ICLARM and Cronulla: Fisheries Division, CSIRO, pp. 195–237.
Kay, J.J. and Schneider, E. (1994) Embracing complexity. The challenge of the ecosystem approach. Alternatives 20, 32–9.
Kerfoot, W.C. (1987) Cascading effects and indirect pathways. In Kerfoot, K.C. and Sih, A., eds. Predation: Direct and Indirect Impacts on Aquatic Communities. Hanover and London: University Press of New England, pp. 57–70.
Kimmins, J.P. (Hamish) (1991a$) The future of the forested landscapes of Canada. Forestry Chron. 67, 14–18.
Kimmins, J.P. (Hamish) (1991b$) Sustainable forestry: can we use and sustain our forests. Edmonton: University of Alberta, Forest Industry Lecture Series 27. 16 pp.
Kimmins, J.P. (Hamish) (1993) Ecology, environmentalism and green religion. Forestry Chron. 69, 285–9.
Knecht, R.W. and Cicin-Sain, R. (1993) Ocean management and the large marine ecosystem concept: taking the next step. In Sherman, K., Alexander, L.M. and Gold, B.D., eds. Large Marine Ecosystems V: Stress, Mitigation and Sustainability. Washington, DC: AAAs Press, pp. 237–41.
Knox, G.A. (1994) The Biology of the Southern Ocean. Cambridge: Cambridge University Press. 444 pp.
Laevestu, T. and Hayes, M.L. (1981) Fisheries Oceanography and Ecology. Farnham, Surrey: Fishing News Books.
Larkin, P.A. (1963) Interspecific competition and exploitation. J. Fish. Res. Bd Can. 20, 647–78.
Larkin, P.A. (1966) Exploitation in a type of predator-prey relationship. J. Fish. Res. Bd Can. 23, 349–56.
Larkin, P.A. (1977) An epitaph for the concept of maximum sustained yield. Detroit 1976. Trans. Am. Fish. Soc. 106, 1–11.
Larkin, P.A. (1982) Directions for future research in tropical multispecies fisheries. In Pauly, D. and Murphy, G.I., eds. Theory and Management of Tropical Fisheries (ICLARM Conf. Proc. 9). Manila: ICLARM and Cronulla: Fisheries Division, CSIRO, pp. 309–28.
Laurec, A., Biseau, A. and Charuau, A. (1991) Modelling technical interactions. ICES mar. Symp. 193, 225–36.
Livingston, P.A., Low, L.L. and Marasco, R.J. (1994) Eastern Bering Sea ecosystem trends. Seattle: NMFS, Alaska Fisheries Science Center. 14 pp. + 19 figs.
McGlade, J.M. (1989) Integrated fisheries management models: understanding the limits to marine resource exploitation. In Edwards, E.F. and Megrey, B.A., eds. Mathematical Analysis of Fish Stock Dynamics. Bethesda, MD: Am. Fish. Soc., pp. 139–65.
Magnuson, J.J. (1991) Fish and fisheries ecology. Ecol. Appl. 1(1), 13–26.
Mann, K.H. and Lazier, J.R.N. (1991) Dynamics of Marine Ecosystems. Biological-physical Interactions in the Oceans. Oxford: Blackwell. 466 pp.
May, R.M. (1984) Exploitation of Marine Communities (Life Sciences Res Rep 32, Dahlem Konferenzen). Berlin: Springer-Verlag. 367 pp.
May, R.M., Beddington, J.R., Horwood, J.W. and Shepherd, J.G. (1978) Exploiting natural populations in an uncertain world. Mathl Biosci. 42, 219–52.
May, R.M., Beddington, J.R., Clark, C.W., Holt, S.J. and Laws, R.M. (1979) Management of multispecies fisheries. Science 205, 267–77.
Mount, D.I. (1992) What evidence of ecosystem risk is necessary to influence regulatory and industrial decisions. Adv. mod. env. Toxicol. 20, 31–7.
Muck, P. (1989) Major trends in the pelagic ecosystem off Peru and their implications for management. In Pauly, D., Muck, P., Mendo, J. and Tsukayama, I., eds. The Peruvian Up-welling Ecosystem: Dynamics and Interactions (ICLARM Conf. Proc. 18). Manila, Philippines: ICLARM, pp. 386–403.
Murawski, S.A. (1984) Mixed species yield-per-recruitment analysis accounting for technological interactions. Can. J. Fish. aquat. Sci. 41, 897–916.
Murawski, S.A., Lange, A.M. and Idoine, J.S. (1991) An analysis of technological interactions among Gulf of Maine mixed species fisheries. ICES mar. Sci. Symp. 193, 237–52.
Murdoch, W.W. and Bence, J. (1987) General predators and unstable prey populations. In Kerfoot, W.C. and Sih, A., eds. Predation: Direct and Indirect Impacts on Aquatic Communities. Hanover and London: University Press of New England, pp. 17–30.
Myers, R.A., Barrowman, N.J., Hutchings, J.A. and Rosenberg, A.A. (1995) Population dynamics of exploited fish stocks at low population levels. Science 269, 1106–8.
Neher, P.A., Arnason, R. and Mollett, N. (1989) Rights Based Fishing: Proceedings of the NATO Advanced Research Workshop on Scientific Foundations for Rights Based Fishing. Reykjavik, Iceland, June 27–July 1, 1988. 541 pp.
Nihoul, J.C. (ed.) (1975) Modelling of Marine Systems. (Elsevier Oceanography Series, 10). Amsterdam: Elsevier. 272 pp.
Nikitina, E.N. and Pearse, P.H. (1992) Conservation of marine resources in the former Soviet Union: an environmental perspective. Ocean Development and Intern. Law 23, 369–81.
North Pacific Fisheries Management Council (1994) Ecosystem Considerations 1995: The Plan Teams for the Groundfish Fisheries of the Bering Sea, Aleutian Islands, and the Gulf of Alaska. Seattle: NPFMC. 88 pp.
Olivieri, R.A., Cohen, A. and Chavez, F.P. (1993) An ecosystem model of Monterey Bay, California. In Christensen, V. and Pauly, D. eds. (1993) Trophic Models of Aquatic Ecosystems (ICLARM Conf. Proc. 26). Manila: ICLARM, pp. 315–22.
Overholtz, W.J., Murawski, S.A. and Foster, K.L. (1991) Impact of predatory fish, marine mammals, and seabirds on the pelagic fish ecosystem of the northeastern USA. ICES mar. Sci. Symp. 193, 198–208.
Overholtz, W.J., Edwards, S.F. and Brodziak, J.K.T. (1993) Strategies for rebuilding and harvesting New England groundfish resources. In Kruse, G., Eggers, D.M., Marasco, R.J., Pautzke, C. and Quinn, T.J. II, eds. Management Strategies for Exploited Fish Populations. Fairbanks: University of Alaska, Alaska Sea Grant College Program Report 93–02, pp. 507–27.
Paine, R.T. (1980) Food webs: linkage interaction strength, and community infrastructure. J. Anim. Ecol. 49, 667–85.
Parrish, B.B. (1979) Extracts of a letter from B.B. Parrish, Director, Marine Laboratory, Aberdeen to B.J. Rothschild. In Interim Report of the ACMRR working party on the scientific basis for determining management measures. FAO. Fish. Circ. No. 718, pp. 111–12.
Pauly, D., Muck, P., Mendo, J. and Tsukayama, I. (eds) (1989) The Peruvian Upwelling Ecosystem: Dynamics and Interactions (ICLARM Conf. Proc. 18). Manila: ICLARM. 438 pp.
Pikitch, E.K. (1987) Use of a mixed-species yield-per-recruit model to explore the consequences of various management policies for the Oregon flatfish fishery. Can. J. Fish. aquat. Sci. 44 (Supp. 2), 349–59.
Pikitch, E.K. (1991) Technological interactions in the U.S. West Coast groundfish trawl fishery and their implications for management. ICES mar. Sci. Symp. 193, 253–63.
Platt, D.D. (1993) The System in the Sea: Applying Ecosystems Principles to Marine Fisheries. Island Institute Conf., Harvard, June 16–28, 1992. Vol. 2. Conf. Proc. Island Institute, Rockford, ME. 198 pp.
Polovina, J.J. (1984) Model of a coral reef ecosystem: Part I. The ECOPATH model and its application to French Frigate Shoals. Coral Reefs 3, 1–11.
Polovina, J.J. (1994) Case of the missing lobsters. Nat. Hist. 2, 51–8.
Pope, J.G. (1991) The ICES multispecies assessment working group: evolution insights and future problems. ICES mar. Sci. Symp. 193, 22–33.
Prescott, V. (1993) Role of national political factors in the management of LMEs: evidence from West Africa. In Sherman, K., Alexander, L.M. and Gold, B.D., eds. Large Marine Ecosystems V: Stress, Mitigation and Sustainability. Washington, DC: AAAs Press, pp. 280–98.
Ricker, W.E. (1954) Stock and recruitment. J. Fish. Res. Bd Can. 11, 559–623.
Riffenburgh, R.H. (1969) Stochastic model of interpopulation dynamics in marine ecology. J. Fish. Res. Bd Can. 26, 2843–80.
Russ, G.R. and Alcala, A.C. (1994) Sumilon Island Reserve: 20 years of hopes and frustrations. NAGA, the ICLARM Quarterly (July), 8–12.
Sainsbury, K.J. (1984) The ecological basis of tropical fisheries management. In Pauly, D. and Murphy, G.I., eds. Theory and Management of Tropical Fisheries (ICLARM Conf. Proc. 9). Manila: ICLARM and Cronulla: Fisheries Division, CSIRO, pp. 167–94.
Sainsbury, K.J. (1991) Application of an experimental approach to management of a tropical multispecies fishery with highly uncertain dynamics. ICES mar. Sci. Symp. 193, 301–19.
Schindler, D.W. (1987) Detecting ecosystem responses to anthropogenic stress. Can. J. Fish. aquat. Sci. 44 (Supp. 1), 6–25.
Schindler, D.W. (1990) Experimental perturbations of whole lakes as tests of hypothesis concerning ecosystem structure and function. Oikos 57, 25–41.
Schramm, H. (1994) President's Message. Ecosystem management and other buzzwords. AFS Fish. Manage. Section Newsl. 13(2), 1.
Sherman, K. (1993) Large marine ecosystems as global units for marine resource management — an ecological perspective. In Sherman, K., Alexander, L.M. and Gold, B.D., eds. Large Marine Ecosystems V: Stress, Mitigation and Sustainability. Washington, DC: AAAs Press, pp. 3–14.
Sherman, K., Alexander, L.M. and Gold, B.D. (eds) (1993) Large Marine Ecosystems V: Stress, Mitigation and Sustainability. Washington, DC: AAAs Press. 376 pp.
Simpson, A.C. (1982) A review of the database on tropical multispecies stocks in the southeast Asian region. In Pauly, D. and Murphy, G.I. (eds) Theory and Management of Tropical Fisheries (ICLARM Conf. Proc. 9). Manila: ICLARM and Cronulla: Fisheries Division, CSIRO, pp. 5–32.
Sissenwine, M.P. and Daan, N. (1991) An overview of multispecies models relevant to management of living resources. ICES mar. Sci. Symp. 193, 6–11.
Sissenwine, M.P. and Rosenberg, A.A. (1993) Marine fisheries at a critical juncture. Fisheries 18(10), 6–14.
Slobodkin, L.B. (1963) Growth and Regulation of Animal Populations. New York: Holt, Rinehart and Winston. 184 pp.
Smith, S.J., Hemt, J.J. and Rivard, D. (eds) (1993) Risk evaluation and biological reference points for fisheries management. Can. spec. Publ. Fish. aquat. Sci. 120, 442 pp.
Sparre, P. (1991) Introduction to multispecies virtual population analysis. ICES. mar. Sci. Symp. 193, 12–21.
Steele, J.H. (ed.) (1970) Marine Food Chains. Edinburgh: Oliver and Boyd. 552 pp.
Sugihara, G. (1984) Ecosystems dynamics group report. In May, R.M. (ed.) Exploitation of Marine Communities (Life Science Research Report 32, Dahlem Konferenzen 1984). Berlin: Springer Verlag, pp. 131–53.
Townsend, R.E. and Pooley, S.G. (1994) Effort reduction under limited entry: attrition versus fractional licenses in the Hawaii long line fleet. N. Am. J. Fish. Manage. 14, 297–306.
Travis, J. (1993) Invader threatens Black, Azov Seas. Science 262, 1366–7.
Tullock, G. and Brady, G. (1992) The risk of crying wolf. Adv mod. env. Toxicol. 20, 77–91.
Ulanowicz, R.E. (1986) Growth and Development: Ecosystem Phenomenonology. New York: Springer-Verlag. 203 pp.
Ulanowicz, R.E. and Platt, T. (eds) (1985) Ecosystem theory for biological oceanography. Can. Bull. Fish. aquat. Sci. 213: 260 pp.
Ulanowicz, R.E. and Puccia, C.J. (1990) Mixed trophic impacts in ecosystems. Coenoses 5, 7–16.
Van Dyne, G.M. (ed.) (1969) The Ecosystem Concept in Natural Resource Management. New York: Academic Press. 383 pp.
Walters, C.J. and Hilborn, R. (1978) Ecological optimization and adaptive management. Ann. Rev. Ecol. Syst. 9, 157–88.
Watt, K.E.F. (1968) Ecology and Resource Management. New York: McGraw Hill. 450 pp.
Wilson, J.A., French, J., Kleban, P., McKay, S.R. and Townsend, R. (1991) Chaotic dynamics in a multiple species fishery: a model of community predation. Ecol. Modelling 58, 303–22.
Wooster, W.S. (1993) Is it food? An overview. In Is it Food? Addressing Marine Mammal and Seabird Declines. Workshop Summary. Fairbanks: Alaska Sea Grant Report 93-01, pp. 1–3.
Wulff, F., Field, J.G. and Mann, K.H. (eds) (1989) Network Analysis in Marine Ecology: Methods and Applications. Berlin: Springer-Verlag. 284 pp.