Barred owls and landscape attributes influence territory occupancy of northern spotted owls.

We used multi-season occupancy analyses to model 2 fates of northern spotted owl territories in relation to habitat amount, habitat fragmentation, and the presence of barred owls in Washington State, USA, 1989-2005. Local colonization is the probability a territory unoccupied by a spotted owl in year would be occupied in year  + 1, and local extinction is the probability a territory that was occupied by a spotted owl in year would be unoccupied in year  + 1. We found a negative relationship between local extinction probability and amount of late-seral forest edge.