Possible Alteration of Circadian Rhythms in Bats at a Heavy Metal Contaminated Site

Abstract

The ability of organisms to exhibit daily patterns of behavior and hormone regulation is deeply connected to the changing light levels over any 24 hour solar cycle. Both morphological and physiological mechanisms allow for proper timing of key behaviors such as emergence and sleep so as to maximize benefits and minimize risks to survival. We were interested in how heavy metal contamination may affect circadian activity levels in wild bat populations. Specifically we hoped to determine if the emergence time of bats within the Tar Creek Superfund Site (TC) in northeastern Oklahoma differed from that at two uncontaminated locations within the Oologah Wildlife Management Area (OWMA, Oklahoma). We recorded emergence times visually and by using an acoustical bat detector and compared them to sunset times at each location. We found emergence times of bats at TC occurred significantly later (p = 0.022, df = 3) than at the combined
locations within OWMA. ©2015 Oklahoma Academy of Science