Back To Ecosystem Based Management

By Sheril Kirshenbaum | February 19, 2010 10:58 am

This is the sixth in a series of guest posts by Joel Barkan, a previous contributor to “The Intersection” and a graduate student at the Scripps Institution of Oceanography. The renowned Scripps marine biologist Jeremy Jackson is teaching his famed “Marine Science, Economics, and Policy” course for what may be the last time this year (along with Jennifer Jacquet), and Joel will be reporting each week on the contents of the course.

It seems simple enough: we should manage our marine resources to protect the whole ecosystem, not just a single species. That’s the basic premise of ecosystem-based management (EBM), the topic of this week’s class at Scripps (Read a previous post on EBM by Sheril here). EBM is all about interactions: between predator and prey, parasite and host, nutrients and phytoplankton, humans and our environment. The need for EBM comes from too many cases of a single-species management practice resulting in unintended impacts on the surrounding environment.

Take the Atlantic cod, for example, a fish that supported America’s most lucrative fishery in the 19th and most of the 20th century. Atlantic cod was overfished so heavily that its stocks are now virtually commercially extinct. We’ve all eaten cod, but you might not know what it looks like: it’s a voracious predator with an impressive set of teeth. Its jaws are powerful enough to easily crack the shell of all but the biggest, feistiest Maine lobsters. When cod stocks were depleted, the lobster populations boomed, free from the threat of one of their only predators. Now the North Atlantic lobster fishery thrives, while the cod fishery lays dormant. Lobsters are lured into traps by dead, smelly fish, which means millions of tons of Atlantic herring are caught every year and sold to lobstermen as bait. My personal research has indicated that increased herring fishing effort may have driven humpback and fin whales away from their traditional feeding grounds in the Gulf of Maine in search of a different food source.

Did you follow that? We went from cod to lobster to herring to humpbacks. To be fair, even the most fervent supporter of EBM would have struggled to predict that exploiting cod might eventually affect whales. But if the theory of EBM had been around during the heyday of the North Atlantic cod fishery (EBM has only entered the mainstream consciousness within the past two decades), someone likely would have at least raised a red flag. At its core, EBM is about taking a precautionary approach to management. Marine resource managers have historically thrown caution to the wind, even in the face of scientific uncertainty. This reckless style may become a thing of the past—NOAA chief Jane Lubchenco is one of EBM’s most prominent supporters.

EBM is a great idea in theory, but the practice is difficult to implement and even define. I just spent a three hour class learning and talking about it, but before writing this, I still had to brush up on the topic with NOAA’s 1998 Report to Congress on EBM. We can attribute the haziness of EBM to its relative infancy as a concept. As more scientists and policymakers continue to embrace EBM, we may see it transition from merely a good idea to a realistic strategy.

CATEGORIZED UNDER: Conservation, Marine Science

Comments (9)

  1. Mark

    One of the shortcomings of ecosystem based management has been the tendency to confuse measurement for management. The sweet spot rests somewhere between the observational scientist’s penchant for measuring everything, everywhere, all the time and the prediction fetish of physics envy. I’m skeptical that the sweet spot is discoverable.

  2. Busiturtle


    My sense is EBM is hazy because it assumes one can know things that are unknowable. The philosophy of EBM sounds good but any strategy has to take into account the uncertainty of man’s understanding of the marine ecosystem and an appreciation of the natural dynamics it exhibits. Since management perfection is unlikely the more important goal should be to define measures of ecosystem robustness and monitor how well those benchmarks are realized.

  3. gillt

    Mark: “…observational scientist’s penchant for measuring everything, everywhere, all the time and the prediction fetish of physics envy.”

    Suddenly I wish I hadn’t given up troll bait for Lent.

  4. Mark

    You might consider Judith Layzer’s 2008 Natural Experiments: Ecosystem-Based Management and the Environment. She poses the right question. Does “Ecosystem Based Management” actually deliver better environmental results?

  5. So given the choice between cod and lobsters, how does one decide?

  6. Fishsense

    What claptrap. Codfish is nowhere enar “commercially extinct” and the annual US quota for herring isn’t, and never has been, anywhere close to a million tons. If this itypifies what is being taught in our nations’s schools it’s no wonder the American educational system is going down the toilet.

  7. Mark

    Lab lemming: “So given the choice between cod and lobsters, how does one decide?”
    The principles of “ecosystem-based management” include stakeholder collaboration to identify the desired state of multiple ecosystem attributes. So it’s quite straightforward. First assume consensus is reached among competing or mutually exclusive values in a legitimate, fair, and timely process that involves all stakeholders. Second, …

  8. gillt

    Wow Fishsense, considering the Atlantic Cod is red listed as a threatened species, I’d say you have it about exactly backwards.

    Now please remove the Fish from your handle.

  9. Joel Barkan

    Fishsense: thanks for pointing that out. I wrote “millions” when I meant to write “thousands.” Atlantic herring landings in the last decade have ranged from 78k – 121k.

    I can assure you that my slip-up does not reflect the quality of my education. Nor does this change the fact that we’re harvesting an important forage species to use as bait for the ultimate luxury fishery. As a Maine native, I support the lobster fishery, but I think management would benefit by incorporating more principles of EBM into its policies.

    If the Atlantic cod is “nowhere near” commercially extinct, then why did Canada shut down its cod fisheries in the mid-90s? If cod is not commercially extinct, then it’s certainly knocking at the door, especially when a country feels the need to suspend fishing activity to let the stocks recover. The current North Atlantic cod fishery is a classic example of the Shifting Baselines syndrome, where the cod biomass is deemed large enough to fish despite existing at a tiny fraction of what it once was. I encourage you to read Mark Kurlansky’s “Cod” if you haven’t already.


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About Sheril Kirshenbaum

Sheril Kirshenbaum is a research scientist with the Webber Energy Group at the University of Texas at Austin's Center for International Energy and Environmental Policy where she works on projects to enhance public understanding of energy issues as they relate to food, oceans, and culture. She is involved in conservation initiatives across levels of government, working to improve communication between scientists, policymakers, and the public. Sheril is the author of The Science of Kissing, which explores one of humanity's fondest pastimes. She also co-authored Unscientific America: How Scientific Illiteracy Threatens Our Future with Chris Mooney, chosen by Library Journal as one of the Best Sci-Tech Books of 2009 and named by President Obama's science advisor John Holdren as his top recommended read. Sheril contributes to popular publications including Newsweek, The Washington Post, Discover Magazine, and The Nation, frequently covering topics that bridge science and society from climate change to genetically modified foods. Her writing is featured in the anthology The Best American Science Writing 2010. In 2006 Sheril served as a legislative Knauss science fellow on Capitol Hill with Senator Bill Nelson (D-FL) where she was involved in energy, climate, and ocean policy. She also has experience working on pop radio and her work has been published in Science, Fisheries Bulletin, Oecologia, and Issues in Science and Technology. In 2007, she helped to found Science Debate; an initiative encouraging candidates to debate science research and innovation issues on the campaign trail. Previously, Sheril was a research associate at Duke University's Nicholas School of the Environment and has served as a Fellow with the Center for Biodiversity and Conservation at the American Museum of Natural History and as a Howard Hughes Research Fellow. She has contributed reports to The Nature Conservancy and provided assistance on international protected area projects. Sheril serves as a science advisor to NPR's Science Friday and its nonprofit partner, Science Friday Initiative. She also serves on the program committee for the annual meeting of the American Association for the Advancement of Science (AAAS). She speaks regularly around the country to audiences at universities, federal agencies, and museums and has been a guest on such programs as The Today Show and The Daily Rundown on MSNBC. Sheril is a graduate of Tufts University and holds two masters of science degrees in marine biology and marine policy from the University of Maine. She co-hosts The Intersection on Discover blogs with Chris Mooney and has contributed to DeSmogBlog, Talking Science, Wired Science and Seed. She was born in Suffern, New York and is also a musician. Sheril lives in Austin, Texas with her husband David Lowry. Interested in booking Sheril Kirshenbaum to speak at your next event? Contact Hachette Speakers Bureau 866.376.6591 For more information, visit her website or email Sheril at


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