Advising Fisheries

Case Study from IIASA Annual Report 2011: 

Current research focuses on providing fishery managers with tools to evaluate the impacts of fisheries-induced evolution in their standard assessment practices

For several years, IIASA's Evolution and Ecology Program (EEP) has highlighted the fact that the pace of Darwinian evolution was being accelerated in oceans and lakes through large-scale fishing operations by commercial vessels and private anglers. Convincing fishery managers that fish are responding to fishing by evolving rapidly over decades, rather than slowly across the centuries, has been facilitated through EEP's steadfast contacts with the International Council for the Exploration of the Sea (ICES), the world’s oldest intergovernmental organization concerned with marine and fisheries science.

In the context of an international ICES expert group, EEP scholars have been developing a practical framework for managers to conduct evolutionary impact assessments (EvoIAs) for the fish populations they oversee. The EvoIA framework represents the first effort to apply a structured approach to assessing the evolutionary consequences of fishing: it is based on four modules that enable managers to assess whether observed changes in fish populations are due to environmental change or are heritable, to study the consequences such changes have for stock dynamics, to account for their socioeconomic implications, and to optimize strategies for managing fish stocks accordingly.

The removal of larger, older fish from fish populations through large-scale fishing is shifting the evolutionary balance toward earlier reproduction. In the Northeast Arctic cod, for example, this has reduced the number of eggs a female produces in her first reproductive season by half over the last 75 years. The genetic changes induced by fishing are thus altering the potential “catch” for many years to come. This is especially worrisome, as evolutionary decline is relatively fast, but recovery from it is much slower.

Many stakeholders benefit from sustainable fisheries through the provision of food,
employment, revenue, and recreational services, including individual anglers, commercial
fishing enterprises, coastal communities, consumers, tourists, and conservation groups.
By coupling biological models of fish stocks with corresponding socioeconomic models,
EEP’s research helps to describe quantitatively what these different stakeholders derive
from a fish stock, or will lose through its depletion, thus aiding decision makers deal with the challenge of reconciling interests among all stakeholder groups.

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Last edited: 19 July 2013

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