Connectivity, passability and heterogeneity interact to determine fish population persistence in river networks.

ABSTRACT: The movement of fish in watersheds is frequently inhibited by human-made migration barriers such as dams or culverts. The resulting lack of connectivity of spatial subpopulations is often cited as a cause for observed population decline. We formulate a matrix model for a spatially distributed fish population in a watershed, and we investigate how location and other characteristics of a single movement barrier impact the asymptotic growth rate of the population. We find that while population growth rate often decreases with the introduction of a movement obstacle, it may also increase due to a 'retention effect'. Furthermore, obstacle mortality greatly affects population growth rate. In practice, different connectivity indices are used to predict population effects of migration barriers, bu

SUBMITTER: Samia Y 

PROVIDER: S-EPMC4614453 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature