Modeling nest survival of cavity‐nesting birds in relation to postfire salvage logging

Abstract

AbstractSalvage logging practices in recently burned forests often have direct effects on species associated with dead trees, particularly cavity‐nesting birds. As such, evaluation of postfire management practices on nest survival rates of cavity nesters is necessary for determining conservation strategies. We monitored 1,797 nests of 6 cavity‐nesting bird species: Lewis's woodpecker (Melanerpes lewis), hairy woodpecker (Picoides villosus), black‐backed woodpecker (P. arcticus), northern flicker (Colaptes auratus), western bluebird (Sialia mexicana), and mountain bluebird (S. currucoides) from 1994 to 2004 in ponderosa pine (Pinus ponderosa), mixed‐severity burned forests (partially logged and unlogged) of Idaho, USA. Based on a priori hypotheses, we modeled daily survival rate (DSR) of nests as a function of abiotic (temperature, precipitation), temporal (time since fire, calendar year) and biotic factors (distance to unburned forest, nest height, and tree harvest [partial‐salvage logging vs. unlogged]). Multiple abiotic and biotic factors, other than direct effects of salvage logging, affected daily survival rates of breeding cavity‐nesting birds. Hairy woodpecker was the only species in which partial‐salvage logging had a measurable, negative impact on DSR. Managers implementing carefully planned salvage logging prescriptions that include both unlogged reserves and partially logged areas can expect to maintain habitat for successfully breeding cavity‐nesting birds of the interior northwestern United States. Our results also suggest that nest survival for some species of cavity‐nesting birds could be improved if unlogged reserves are located centrally in postfire forests, distant from unburned habitats that potentially serve as sources of nest predators. © 2011 The Wildlife Society.