| Abstrakt: |
Reducing fire-induced mortality of cavity trees used by red-cockaded woodpeckers (Picoides borealis) is a challenge and concern in managing this federally endangered species. Prior to the 2001 burning season, 814 active and inactive longleaf pine (Pinus palustris) cavity trees on Eglin Air Force Base (AFB) in northwest Florida, USA, were prepared via 6 protection methods (combinations of mechanical, hand, and backfiring preparation) and monitored for postburn survival after 1 year. We collected data on a suite of variables that may be useful in determining cavity tree predisposition to tire-induced mortality. Mortality of protected trees (2.62%) was significantly lower than that of unprotected trees (6.18%), and protection methods did not differ in their effectiveness at preventing mortality. Bark char was significantly more prevalent on unprepared control trees than protected trees, but no differences were apparent among protection treatments. Mechanical clearing alone took the least amount of time and resources; therefore, we determined mechanical clearing to be the most efficient preparation method. Stern char, needle scorch, percent sap cover, and whether the cavity burned were the characteristics most closely related to mortality 1 year postfire. We recommend that the percent of the bole covered in sap and cavity height be considered when preparing to reduce stem char, needle scorch, and the incidence of burned-out cavities. Managers of red-cockaded woodpecker populations can use these results and recommendations to adjust their burn program, improve the efficiency of their cavity tree protection methods, and better target cavity provisioning for maintaining a viable pool of cavity trees. [ABSTRACT FROM AUTHOR] |
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