Rainey 1998). Western mastiff bats show high roost lability, with some roost sites being used faithfully and others only being used temporarily, both within and between seasons (Best et al. 1996; Krutzsch 1955; Pierson and Rainey 1998). Some roost sites may be critical for local populations, but the species’ roosting ecology is largely unknown (Pierson and Rainey 1996). Foraging habitat in California includes chaparral, coastal scrub, grasslands, floodplains, oak woodland, ponderosa pine forest, dry desert wash, meadow areas, and agriculture (Pierson and Rainey 1998). Western mastiff bat is frequently observed foraging in broad, open areas (Pierson and Rainey 1998) and may travel up to 25 kilometers (15.5 miles) from roosting sites to forage (Best et al. 1996). There is no evidence that western mastiff bats are foraging habitat specialists, although in a study in Mexico City, they were only detected in natural forest habitats and not in habitats used by some other bat species in more urbanized parts of the city, including city parks, residential areas, and illuminated areas (Avila-Flores and Fenton 2005). Roosting and foraging habitat associations for the western mastiff bat in the Plan Area are shown in Table 1. Table 1. Habitat Associations for Western Mastiff Bat Land Cover Habitat Supporting Type Designation Habitat Parameters Information Rocky Roosting 50% to 100% rocky Best et al. 1996; outcrops, slopes Pierson and crevices, cliffs Rainey 1998 Woodlands and Foraging Riparian woodlands and Best et al. 1996; forest, scrub, forest, desert wash, Pierson and chaparral, desert scrub within 25 Rainey 1998 grassland, kilometers (15.5 miles) of agriculture roosting site Foraging Requirements Western mastiff bat forages for a variety of small to large, low-altitude and weak-flying insects that it catches in flight from near ground level
Rainey 1998). Western mastiff bats show high roost lability, with some roost sites being used faithfully and others only being used temporarily, both within and between seasons (Best et al. 1996; Krutzsch 1955; Pierson and Rainey 1998). Some roost sites may be critical for local populations, but the species’ roosting ecology is largely unknown (Pierson and Rainey 1996). Foraging habitat in California includes chaparral, coastal scrub, grasslands, floodplains, oak woodland, ponderosa pine forest, dry desert wash, meadow areas, and agriculture (Pierson and Rainey 1998). Western mastiff bat is frequently observed foraging in broad, open areas (Pierson and Rainey 1998) and may travel up to 25 kilometers (15.5 miles) from roosting sites to forage (Best et al. 1996). There is no evidence that western mastiff bats are foraging habitat specialists, although in a study in Mexico City, they were only detected in natural forest habitats and not in habitats used by some other bat species in more urbanized parts of the city, including city parks, residential areas, and illuminated areas (Avila-Flores and Fenton 2005). Roosting and foraging habitat associations for the western mastiff bat in the Plan Area are shown in Table 1. Table 1. Habitat Associations for Western Mastiff Bat Land Cover Type Habitat Designation Habitat Parameters Supporting Information Rocky outcrops, crevices, cliffs Roosting 50% to 100% rocky slopes Best et al. 1996; Pierson and Rainey 1998 Woodlands and forest, scrub, chaparral, grassland, agriculture Foraging Riparian woodlands and forest, desert wash, desert scrub within 25 kilometers (15.5 miles) of roosting site Best et al. 1996; Pierson and Rainey 1998 Foraging Requirements Western mastiff bat forages for a variety of small to large, low-altitude and weak-flying insects that it catches in flight from near ground level
Western%20Mastiff%20Bat.docx