Carl Walters

Last updated
Carl Walters
Born
Carl John Walters

Alma mater Colorado State University
Known forFisheries stock assessments, adaptive management, ecosystem modeling
AwardsFellow of the Royal Society of Canada (1998), Mote Eminent Scholar at FSU (2000-2001), Pew Fellow in Marine Conservation (2001), Murray A. Newman Award for Marine Conservation (2005), Volvo Environment Prize (2006), American Fisheries Society Award of Excellence (2006), Timothy R. Parsons Medal (2007), Order of British Columbia (2019)
Scientific career
Fields Zoology, fisheries science, population ecology
Institutions UBC Fisheries Centre, University of British Columbia
Doctoral advisor Robert E. Vincent
Notes

Carl Walters (born 1944) is an American-born Canadian biologist known for his work involving fisheries stock assessments, the adaptive management concept, and ecosystem modeling. [1] Walters has been a professor of Zoology and Fisheries at the University of British Columbia since 1969. [2] He is one of the main developers of the ecological modelling software Ecopath. [3] His most recent work focuses on how to adjust human behaviors in environments that are full of uncertainty. [1] He is a recent recipient of the Volvo Environment Prize (2006). [4] In 2019, Dr. Walters became a Member of the Order of British Columbia. [5]

Contents

Education

Carl Walters graduated from Bakersfield College with an A.A in 1963 and continued to Humboldt State College to graduate with a B.S. in 1965. After Walters graduated, he went to Colorado State University to study the "Distribution and production of midges in an alpine lake" under the advisement of Dr. Robert E. Vincent. After obtaining his M.S. in 1967, Walters stayed on with R.E. Vincent to get his doctorate on the "Effects of fish introduction on invertebrate fauna of an alpine lake" and graduated in 1969. Walters did not go on for a postdoctoral position; instead he almost immediately started working at the University of British Columbia in Vancouver, British Columbia, Canada. [2]

Career

Walters's first professorship was at the University of British Columbia as an Assistant Professor in the UBC Institute for Animal Resource Ecology. In 1977, he became an Associate Professor and then a Professor in 1982. Prior to his professional appointment at UBC, Walters worked for the California Department of Fish and Game and was also a graduate fellow, a consultant, and an aide on numerous occasions. [2] He has taken sabbaticals to the International Institute of Applied Systems Analysis in Vienna, the University of Florida, where he is an adjunct professor, and Australia. [2] He has been on the editorial board for multiple journals including the Canadian Journal of Fisheries and Aquatic Sciences, Conservation Ecology, and Ecosystems and has been the associate editor of the Journal of Applied Mathematics and Computation and the Northwest Environmental Journal. [2] He was the editor of the Open Fish Science Journal. Walters also served, and continues to serve, as a consultant to many government agencies.

Interests

Walters uses mathematical modeling to understand how to successfully manage harvestable fisheries in a time of high uncertainty. [1] [2] He specializes in fisheries stock assessments (e.g cod, salmon, anchoveta), adaptive management strategies, and ecosystem modeling. [1] [2] [6] [7] One of his goals has been, and continues to be, to try to bridge the gap between fisheries management, government, and fishing industries in order to provide accurate information to use in successfully and actively managing fisheries. His work in modeling population dynamics and active adaptive management has made Walters a valuable member of the scientific community.

Contributions

Foraging Arena Theory

Other modeling equations like the Beverton-Holt model and the "hockey stick" model by Barrowman and Myers (2000) try to explain density dependent effects of juvenile fish populations using processes like recruitment and the number of eggs produced. [8] [9] [10] Fisheries biologists and population ecologists have used the Beverton-Holt model since the 1960s to describe the "stock-recruitment" relationship. [9] However, Walters believed that juvenile behavior could also explain the density dependent relationship that Beverton and Holt and Barrowman and Myers described. Walters thought that juvenile behavior, in conjunction with habitat, could explain the density dependency seen when foraging for prey and avoiding predators. [10] [9] Walters wanted to give scientists a better understanding of the processes that drive density dependent fluctuations in ecosystem statistics (birth and death rates). [10] The foraging arena theory is also used, in conjunction with the ecosystem simulation program Ecopath with Ecosim, to account for the indirect effects and trophic cascades seen in populations. [10]

Adaptive management

One of Walters biggest concerns in the rapidly changing environment is how managers can successfully manage fisheries stocks in lieu of the uncertainty in making decisions. [10] His concept of active adaptive management involves large-scale experimentation, or "learning-by-doing", in order to understand the population dynamics in fish communities and to aide in the decision-making process done by policy makers. [11] Walters encourages other scientists, managers, and policy makers to embrace the uncertainty in experiments and decisions and to develop ecosystem models based on the uncertainties in order to make multiple hypotheses instead of just one hypothesis. [10] Although active adaptive management has gained much support from the scientific community, there is still great hesitation from scientists and managers to implement these large-scale experiments. [12] [13] These hesitations arise from large monetary costs for the experiments as well as the monitoring of the experiments, lack of an individual willing to take on the daunting task of organizing the experiments, the limitations of models to perfectly represent an ecosystem, and the conflicting ecological values between different interest groups. [13] Although there are concerns when executing active adaptive management strategies, there is a growing need to modify the current methods for exploring and understanding ecosystems, especially on a larger scale, and active adaptive management strategies aim to do exactly that.

Selected publications

Books
Journal publications

Awards

Related Research Articles

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<span class="mw-page-title-main">Sustainable fishery</span> Sustainable fishing for the long term fishing

A conventional idea of a sustainable fishery is that it is one that is harvested at a sustainable rate, where the fish population does not decline over time because of fishing practices. Sustainability in fisheries combines theoretical disciplines, such as the population dynamics of fisheries, with practical strategies, such as avoiding overfishing through techniques such as individual fishing quotas, curtailing destructive and illegal fishing practices by lobbying for appropriate law and policy, setting up protected areas, restoring collapsed fisheries, incorporating all externalities involved in harvesting marine ecosystems into fishery economics, educating stakeholders and the wider public, and developing independent certification programs.

<span class="mw-page-title-main">Fisheries management</span> Regulation of fishing

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Fisheries science is the academic discipline of managing and understanding fisheries. It is a multidisciplinary science, which draws on the disciplines of limnology, oceanography, freshwater biology, marine biology, meteorology, conservation, ecology, population dynamics, economics, statistics, decision analysis, management, and many others in an attempt to provide an integrated picture of fisheries. In some cases new disciplines have emerged, as in the case of bioeconomics and fisheries law. Because fisheries science is such an all-encompassing field, fisheries scientists often use methods from a broad array of academic disciplines. Over the most recent several decades, there have been declines in fish stocks (populations) in many regions along with increasing concern about the impact of intensive fishing on marine and freshwater biodiversity.

Adaptive management, also known as adaptive resource management or adaptive environmental assessment and management, is a structured, iterative process of robust decision making in the face of uncertainty, with an aim to reducing uncertainty over time via system monitoring. In this way, decision making simultaneously meets one or more resource management objectives and, either passively or actively, accrues information needed to improve future management. Adaptive management is a tool which should be used not only to change a system, but also to learn about the system. Because adaptive management is based on a learning process, it improves long-run management outcomes. The challenge in using the adaptive management approach lies in finding the correct balance between gaining knowledge to improve management in the future and achieving the best short-term outcome based on current knowledge. This approach has more recently been employed in implementing international development programs.

<span class="mw-page-title-main">Ecosystem model</span> A typically mathematical representation of an ecological system

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<span class="mw-page-title-main">Milner Baily Schaefer</span>

Milner Baily ("Benny") Schaefer, is notable for his work on the population dynamics of fisheries.

<span class="mw-page-title-main">Population dynamics of fisheries</span>

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<span class="mw-page-title-main">Ecopath</span>

Ecopath with Ecosim (EwE) is a free and open source ecosystem modelling software suite, initially started at NOAA by Jeffrey Polovina, but has since primarily been developed at the formerly UBC Fisheries Centre of the University of British Columbia. In 2007, it was named as one of the ten biggest scientific breakthroughs in NOAA's 200-year history. The NOAA citation states that Ecopath "revolutionized scientists' ability worldwide to understand complex marine ecosystems". Behind this lie more than three decades of development work in association with a thriving network of fisheries scientists such as Villy Christensen, Carl Walters and Daniel Pauly, and software engineers around the world. EwE is funded through projects, user contributions, user support, training courses and co-development collaborations. Per November 2021 there are an estimated 8000+ users across academia, non-government organizations, industry and governments in 150+ countries.

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The following outline is provided as an overview of and topical guide to fisheries:

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References

  1. 1 2 3 4 5 Dr. Carl Walters Archived December 26, 2008, at the Wayback Machine UBC Fisheries Centre, University of British Columbia. Retrieved 24 December 2008.
  2. 1 2 3 4 5 6 7 8 9 Curricula Vitae for Peer Reviewers Archived 2016-03-04 at the Wayback Machine California Fisheries Coalition. Retrieved 24 December 2008
  3. "Home". ecopath.org.
  4. 1 2 "Home". environment-prize.com.
  5. "2019 Recipients : Order of BC" . Retrieved 2019-10-11.
  6. Walters C.J. and McGuire J.J. 1996. Lessons for stock assessment from the northern cod collapse. Rev. Fish. Biol. Fisheries 6:125-137
  7. Melnychuk M.C., Welch D.W., Walters C.J., and Christensen V. 2007. Riverine and early ocean migration and mortality patterns of juvenile steelhead trout (Oncorhynchus mykiss) from the Cheakamus River, British Columbia. Hydrobiologia. 582: 55-65.
  8. Barrowman N.J. and Myers R.A. 2000. Still more spawner-recRuitment curves: the hockey stick and its generalizations. Can. J. Fish. Aquat. Sci.57: 665-676.
  9. 1 2 3 Walters C.J. and Juanes F. 1993. Recruitment limitation as a consequence of optimal risk-taking behaviour by juvenile fish. Can. J. Fish. Aquat. Sci.50:2058-2070.
  10. 1 2 3 4 5 6 Walters CJ and Martell S (2004) Fisheries Ecology and Management. Princeton, New Jersey, Princeton University Press.
  11. Walters, C.J. 1987. Adaptive policy design for fisheries management: active versus passive policies. In L.W. Botsford [Ed.], Perspectives on Applied Ecology. U. Calif. Press, Davis.
  12. Hilborn, R. and Walters C.J. 1991. Quantitative Fisheries Stock Assessment and Management. Chapman-Hall, Pub. Co., New York, USA. (580 pp)
  13. 1 2 Walters, C. 2007. Is adaptive management helping to solve fisheries problems? Ambio.36:304-307.
  14. "Welcome to the Royal Society of Canada | the Royal Society of Canada". Archived from the original on 2016-11-03. Retrieved 2008-12-23.
  15. "Pew Institute for Ocean Science". Archived from the original on 2009-01-17. Retrieved 2008-12-23.
  16. "American Fisheries Society". Archived from the original on 2010-03-05. Retrieved 2008-12-23.
  17. "The Timothy R. Parsons Medal". Archived from the original on 2006-10-02. Retrieved 2023-11-26.