Overfishing: What everyone needs to know
Ray Hilborn, with Ulrike Hilborn
Many fisheries scientist know that it’s hard to use an often unqualified term like ‘overfishing’. The specifics of overfishing mean many things to many people, but a general definition would be fishing a stock beyond its ability to produce maximum biomass or profit. (See, already two different definitions!) Regardless of a specific definition, due to substantial efficiencies made to effort—such as the steam engine—overfishing is largely a phenomena of the past 100 years. While most can agree that overfishing is an undesirable outcome, the debate generally starts at when to decide that overfishing is occurring. After all, fishermen see one type of data, scientists see another, and still other groups find reasons to cite overfishing.
|Overfishing exists throughout the world. (Source: knowledge.allianz.com)|
Given the clutter around the overfishing debate, earlier this month fisheries scientist Ray Hilborn published a
short book (168 pages) on overfishing that will be reviewed here. The book takes an interesting approach as chapters consist of a series of questions that are answered in a paragraph to a page or so (all text, no illustrations). In this way, the book easy easily read, and chapters and topics are easily revisited.
The book’s chapters follows unofficial themes. First, Hilborn devotes the first five chapters to discussing what overfishing is. He discusses overfishing in general as well as cites some historical case studies, including several pages devoted to whaling. After a very brief chapter on stock recovery, he writes about the current state of the fisheries management, while taking the time to define commonly used terms like stock assessment and certified fishery, and referring to Eastern Bering Sea pollock as a case study of when fisheries management works well. (And yet despite the near unanimous agreement that Eastern Bering Sea pollock are well managed, some still argue!)
|Bering Sea pollock: overfished? No. (Source: pspafish.net)|
The next few chapters discuss—very broadly—different types of fisheries: mixed, deepwater, illegal, and others. There are not specific citations in the text, yet where appropriate, Hilborn might refer to a paper from a well-known journal. (I should also note that the book comes with a modest, chapter-organized bibliography for further inquiry.) He generally does a good job at summarizing the status of these fisheries, though the limited text devoted to each might be better suited to someone unfamiliar with the fisheries and is less likely to satisfy someone already familiar with the topic.
The last few chapters focus on ecosystem impacts of fishing and marine protected areas. While Hilborn is decidedly positive that the problems of overfishing can be fixed (we have the know-how) and that there are benefits to marine protected areas and ecosystem-based management, he is also realistic that overfishing will not end in every case. Throughout the book, he takes time to come back to the fact that fisheries are often managed by societies and legislators who ultimately decide levels of fishing. In smaller fisheries and less developed nations, the results are more variable as open access fisheries and no enforcement can have hugely negative effects on a fishery and ecosystem, while catch shares and territorial rights (as well as lessons learned) have been a recipe for success in some places.
|The Great Barrier Reef is considered the world’s largest marine protected area (MPA), yet it is not protected from climate change, ocean acidification, run-off, oil spills, invasive species, and a host of other threats. (Source: rockenfantasia.com)|
All-in-all, fisheries science can be a large discipline, and many of us (author included) are occasionally guilty of becoming comfortable in a particular fishery, or even methodology. Overfishing: What Everyone Needs to Know will not leave you knowing everything about the present status of fisheries science and management, but the chapters covering unfamiliar topics might be a good refresher. Additionally, the book would be a nice addition (and cheap, too) for a survey-type fisheries ecology/science course. Because the chapters really only touch on the current status of a particular topic, I would have liked to see a larger bibliography—some chapters only have 3 suggested readings.
Overfishing: What Everyone Needs to Know by Ray Hilborn, with Ulrike Hilborn, is available in paperback (168 pages) from Oxford University Press for $16.95.