Habitat Occupancy by the Black-Capped Vireo (Vireo atricapillus) Following Prescribed Burns at Kerr Wildlife Management Area

Abstract

The Black-capped Vireo (Vireo atricapillus), a small, migratory passerine, was listed as a federal endangered species in November 1987. This status resulted from a sustained decline in abundance and loss of populations throughout its geographic range. One of the management guidelines in the Black-capped Vireo Recovery Plan is the use of prescribed fire to create and maintain habitat. Fire is used for the reduction and removal of Ashe juniper (Juniperus Ashei) and to promote low growth in deciduous shrubs for Black-capped Vireo nesting. My study examined the occupancy of pastures by Blackcapped Vireos following prescribed burns at the Kerr Wildlife Management Area in the Edwards Plateau of Texas. Population (singing males) and burn records for 1986-2003 were analyzed to determine the re]µ.tionship between fire regimes applied on pastures and population responses by Black-capped Vireos. My results showed that 52.6% of the prescribed burns resulted in population increases within the same year as the burn and 92.1 % within 2 years post-bum. The overall population trend showed a 20-fold increase in singing males. A trend analysis indicated that 81 % of the increase in the number of singing males can be attributed to the prescribed burn regime. An ANOV A showed differences in burn frequencies did not generate the increase in Black-capped Vireo pasture densities. Based on the documented increases within each pasture, however, prescribed fire is recommended as an important management tool to maintain the random interspersion of shrubby, deciduous vegetation, which the Black-capped Vireo selects for breeding territory.