| dc.description.abstract | Bats are an ecologically important vertebrate group, and yet many populations are threatened by habitat destruction, emerging diseases like White-Nose Syndrome, and wind energy development. In order to make targeted conservation efforts for these species, we need to have a better understanding of their basic life history patterns and know which individuals are at most risk (e.g. juveniles vs. adults). Current techniques to determine age in live bats, such as checking for growth plate closure or evidence of sexual maturity, are restricted in their accuracy. Alternatively, bats can be more accurately aged based on level of tooth wear, as tooth enamel wears down over time due to mastication. This method, however, can only be used on dead bats as it requires the jaws to be removed in order to accurately measure the teeth. As bats routinely damage their wing membranes during flight, another potential method of aging bats could be based on wing scar accumulation over time. The purpose of this study was to develop a new method of aging bats based on a combination of tooth wear and wing scarring. Using bat carcasses collected from a wind farm in north-central Texas, we removed lower jaws and measured teeth from 323 bats representing six species. We measured tooth height, the ratio of tooth mid-width to tip-width, and two dimensional surface areas of the canines, first premolars, and molars. We then looked for differences in wear based on species, sex, and the number of wing scars. We found there to be a difference in tooth wear between adults and juveniles for premolar 2, as well as a difference in wing scar index based on age. The two measurements show no correlation, however, across all species and also within eastern red bats. Male hoary bats seem to have over twice the number of wing scars as females, though a larger sample size is needed to further explore this relationship. | |
