| dc.description | Commercial fishing utilizes a variety of gears, all of which are selective with respect to at least some
phenotypic characteristics of individuals such as body size or girth. Empirical evidence is mounting
that such fishing induces rapid evolutionary changes, with consequences for the size structure and
dynamics of the exploited stocks. Here we present the results of life-history models designed to study
fisheries-induced evolutionary changes in body size at maturation, growth, and reproduction in a stock
fished by different gear types. We examine evolutionary endpoints of, and selection pressures on, three
corresponding life-history traits. We show that fishing usually selects for earlier maturation at smaller
size, higher reproductive investment, and faster growth. This is especially true for trawl-like gears,
which are primarily size-selective and remove large fish. On the other hand, gears that only remove
fish within a certain size slot, such as gillnets, can lead to evolutionary bistability and evolution of
delayed maturation. Moreover, gears that are also directly selective on behavioral traits influencing
growth, such as baited lines, can lead to slower growth. Our results also highlight how the
evolutionary effects of fishing are sensitive to changes in mesh size and fishing mortality, commonly
regulated in fisheries management.
Keywords: life histories, maturation, reproductive investment, growth rate, trawls, gillnets, baited
lines | no_NO |
