  The implementation of effective protected areas is one of the central goals
of modern conservation biology. In the context of fisheries management and
marine ecosystem conservation, marine reserves often play a significant role to
achieve sustainable fisheries management. Consequently, a substantial number of
studies have been conducted to establish broad rules for the creation of MPAs,
or to test the effects of MPAs in specific regions. However, there still exist
many challenges for implementing MPAs that are effective at meeting their
goals. Deducing theoretical conditions guaranteeing that the introduction of
marine reserves will increase fisheries yields in age-structured population
dynamics is one such challenge. To derive such conditions, a simple
mathematical model is developed that follows an age-structured metapopulation
dynamics of a sedentary species. The obtained results suggest that a
sufficiently high fishing mortality rate and moderate recruitment success of an
individual's eggs is a necessary for marine reserves to increase fisheries
yields. The numerical calculations were conducted with the parameters of red
abalone (Haliotis rufescens) to visualize and to check validity of the
analytical results. They show good agreement with the analytical results, as
well as the results obtained in the previous works.
