Effects of prescribed burning on breeding birds in a ponderosa pine forest, southeastern Arizona

摘要

A moderately intense, broadcast, understory, prescribed burn in 3 previously unburned ponderosa pine stands in southeastern Arizona felled or consumed 50% of all ponderosa pine snags ≥ 15 cm dbh. Large moderately decayed snags were most susceptible to burning. Large snags in the early stages of decay were preferred as nest sites by cavity-nesting birds. Numbers of live woody plants were reduced by 40%, mortality was greatest among shrubs and small trees. Canopy volume was reduced by 19%, the greatest impact was below 5 m. No species of cavity-nesting birds, or birds that associated with understory vegetation disappeared in the first season after burning, but 3 species decreased, and 1 species increased in abundance. The minor impacts of a single treatment with broadcast understory burning on bird populations will be ephemeral, but a repeated burns could have greater, and more lasting effects on the avian community.