Stratification of Guano Deposits of the Free-Tailed Bat, Tadarida brasiliensis

Spatial and temporal expression of vegetation and atmospheric variability from stable carbon and nitrogen isotope analysis of bat guano in the southern United States

“…After excavation, 10-20 g of guano from each couplet was collected down the profile by scooping A u t h o r ' s p e r s o n a l c o p y into centrifuge tubes and dated by counting the annual dark-light couplets from the surface. We are reasonably confident of our chronology as Altenbach and Petit (1972) had previously shown that annual stratigraphy was easily visible from 1954 to 1971. Moreover, McFarlane and Keeler (1990) had previously used guano deposition from this site as a proxy for Mexican free-tailed bat population at this cave.…”

“…The Mexican free-tailed bat (Tadarida brasiliensis) migrates each summer from Mexico to Arizona and New Mexico (Altenbach and Petit, 1972). Bat caves are sometimes known to contain large deposits of laminated guano that have accumulated for thousands of years (Des Marais et al, 1980;Mizutani et al, 1992a,b).…”

“…Bat caves are sometimes known to contain large deposits of laminated guano that have accumulated for thousands of years (Des Marais et al, 1980;Mizutani et al, 1992a,b). Moreover, the migration patterns of bats sometimes result in annual laminations (Altenbach and Petit, 1972;Mizutani et al, 1992a). T. brasiliensis is a general insectivore whose guano is preserved due to the desiccating nature of desert cave environments (Mizutani et al, 1992a).…”

“…In February 1988, a guano profile approximately 2-m depth was excavated from Eagle Creek Cave that revealed laminations, each couplet was approximately 15-cm thick. Prior studies have shown that each couplet represent one year due to the morphology of the cave coupled with a unique cave ecology (Altenbach and Petit, 1972;Mizutani et al, 1992a). During late spring, the bats arrive at Eagle Creek Cave, and within days the bat population is at its maximum, leading to their guano accumulating on the cave floor as pellets.…”

Guano Subsidy and the Intertibrate Community in Bracken Cave: The World's Larges Colony of Bats

“…This was accomplished by randomly inserting a PVC pipe sampler 0.08 m in diameter and 0.91 m long into the cave floor and determining the taxa richness and abundance of organisms present between the surface and 0.91 m of guano depth. The method for extracting stratified guano for this study is one that was used by Altenbach and Petit (1972) to study the effects of pollution and heavy metals on the environment. This involved inserting a pipe into the guano, digging a trench around it in order to place a stopper at the bottom, and then extracting the pipe or core sampler.…”