Campus News

Three Fish, Four Fish, My Fish, Your Fish:The Economics of Poorly Informed Regulation of Bycatch and Discarding in Ocean Fisheries.

Story posted November 02, 2001

It's a given, among those who fish for a living, that those who make the regulations don't always understand the realities of living under them. Ta Herrera, assistant professor of economics, recently turned an economists eye to regulations involving by-catch, and he found reason to agree with the fishers - though his resulting suggestions might not please them. (Hint, they involve the government and money).

Herrera spoke recently at a faculty seminar.

Herrera studies fish, or more precisely fisheries - the interaction between humans and fish. "I've been asked on occasion why I study fish," he told his audience. "I have an answer - because they're interesting." He gave as evidence an anonymous quote: "Fish are like trees, except they are invisible and they move."

Fisheries are a delicate balance of effort that allows people to benefit from the natural resources of the ocean and but also allows fish to thrive so that their populations aren't depleted.

Regulation is a common means of trying to reach a level of effort (or fishing) when benefits are maximized. Some fisheries are largely self-regulated (Maine's lobster fishery is one example of this), but often, government regulations are employed in an effort to strike this delicate balance. But do they work?

There are a number of types of regulation:


  • Limiting the number of fishers
  • Limiting the type of equipment permitted
  • Seasonal or spatial closures
  • Economic instruments (taxes and tradable quotas)

(Not surprisingly, economists tend to favor economic instruments, Herrera said.)

Herrera has studied limits imposed to regulate bycatch. Different types of fish often inhabit the same terrain, and much of the equipment used in harvesting them is "nonselective," which means someone fishing for pollock, may end up with halibut in the net. Bycatch is the name given to these "non-target" species.

Herrera has refined the definition for bycatch to "the harvest of organisms from which some other group or individual would derive greater benefit." (For example: when a pollock trawler catches halibut. Though the pollock fisher can sell the halibut, it may have to be frozen while the trawler continues fishing for pollock. This means the fish is selling for a lower price than it would be sold for if a halibut fisher sold it fresh.

Though bycatch is detrimental when it leads to the loss of the ecological function of those fish and the loss of profit by others, it also allows for the profitable harvest of the target species (and sale of bycatch can prove profitable as well).

Bycatch is sometimes discarded, rather than sold. Sometimes bycatch is thrown out because there is no economic benefit to keeping it; other times, there is a legal reason for discarding: For example, the fisher doesn't have a license to sell that particular fish, has already caught the limit or would have to pay taxes that make the catch not worth keeping. When fishers discard, a large percentage of those fish that are thrown back die. Worldwide, about 60 billion pounds of fish are discarded each year, according to Herrera.

Regulations that lead to bycatch aren't always the best way to deal with the problem, Herrera said, due to some "asymmetric information."


  • Regulators are onshore, and bycatch and discarding take place at sea.
  • Regulations are based on the catch that is kept, not what is caught initially.
  • Regulations aiming to reduce bycatch often lead to increased discarding.

Herrera offered a few alternatives to "limits" for regulating bycatch. One is "spatially structured controls."

It would be possible, he said, to determine areas where fish populations overlap (and where bycatch is most likely) and reduce the fishing in those areas. This could be done by regulating the depth at which certain types of fish can be harvested.

Regulators could take into account the strategic behavior of the fishers in response to the regulations. Trip limits aren't necessarily the best way to regulate bycatch because fishers behave differently when fishing under limits than they would if they were unconcerned with limits. And some of those reactions actually lead to discarding.

Finally, onboard observers could be used, to reduce the informational asymmetry that often occurs in making regulations.

Though fishers might not like it, Herrera's conclusion was that taxes work best to eliminate discarding and regulate bycatch. But that still leaves room for onboard observers.

Faculty seminars are each wednesday from 12:30 to 1:30 in Main Lounge, Moulton Union.

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