How do sinks affect population persistence? Let me count the ways

Sinks and ecological traps pose conservation dilemmas for declining populations, with management decisions often required without knowledge of how sinks impact regional dynamics.  Emergent source-sink dynamics in a series of divergent case-study simulations (northern spotted owls, black-capped vireos, Ord’s kangaroo rat) revealed that sinks can: be harmful if they are ‘black holes’ or divert individuals away from better habitats, helpful in delaying imminent decline, have little impact, or have differential effects on population size and extinction risk.  Careful evaluation of sink contributions is needed to create effective management and conservation plans.