Transient inconsistency between population density and fisheries yields
under bycatch persistence
Abstract
Recent studies have demonstrated the great advantages of marine reserves
in solving bycatch problems by maintaining the persistence of endangered
species without sacrificing the fisheries yields of target species.
However, transient phenomena rather than equilibrium states of
population dynamics still require further research. Here, with a simple
and general model, the transient dynamics of strong stock fish species
are investigated under the condition of weak stock persistence. A
surprising and counter-intuitive finding is that fisheries yields can
strongly fluctuate even if population density both inside and outside
marine reserve only slightly varies, leading to transient inconsistency
between the population densities and fisheries yields. This finding
suggests that population density dynamics cannot be used to predict the
transient phenomena of fisheries yields (or vice versa) in fisheries
management. These results will deepen our understanding of the transient
phenomenon in marine ecology.