PARENT SESSION
Oral Session #81: Pollination and Dispersal.
Presiding: T. Ricketts
Thursday, August 8. 9:00 AM to 11:30 AM. Grand Ballroom Central, Radisson.

Effects of forest fragmentation on nectarivorous bat foraging in tropical dry forest in Jalisco, Mexico.

Stoner, Kathryn^*,1, Quesada, Mauricio¹, Rosas-Guerrero, Victor¹, Lobo, Jorge², ¹ Instituto de Ecologia, UNAM, Morelia, Michoacan, MEXICO² Universidad de Costa Rica, San Pedro, COSTA RICA

ABSTRACT- Few studies have documented the effects of forest fragmentation on the foraging ecology of vertebrate pollinators. Our study was designed to quantify foraging of nectarivorous bats in disturbed areas and undisturbed forests by filming their foraging behavior in the chiropterophilic flowers of the neotropical tree Ceiba grandiflora Rose(Bombacaceae). The study was conducted in tropical dry forest in Jalisco, Mexico from March through May 2001. In 50 nights (225 hours), 25 flowers from 15 trees were filmed in disturbed areas and 34 flowers from 19 trees were filmed in undisturbed forest. Forest fragmentation significantly affected the foraging of Glossophaga soricina and the endangered species M. harrisoni. Eighty-eight floral visitations were observed for M. harrisoni during 6 nights exclusively in undisturbed forest while 133 visits of G. soricina were observed during 9 nights in disturbed areas and 453 visits during 28 nights in undisturbed forest. Leptonycteris curasoae is the only species that appears to be less affected by forest fragmentation, being observed for 211 visits in 14 nights in disturbed areas and 316 visits during 20 nights in undisturbed areas. All 3 species were effective pollinators making contact with the stigma and anther in 41%, 58%, and 81% respectively for G. soricina, L. curasoae, and M. harrisoni.

KEY WORDS: Forest fragmentation, Nectarivourous bats, Pollination ecology, Tropical dry forest