Burning the Leafy Blanket: Winter Prescribed Fire and Litter Roosting Bats
Some bat species, including eastern red bats, roost for short periods beneath leaf litter on the forest floor during winter in the southeastern United States, a region subjected to frequent fire. The variability of burns and the effects of litter and duff moisture on forest-floor temperatures during winter burning could influence potential survival for bats beneath the leaf litter if they are unable to escape oncoming flames. Forest Service scientists measured temperatures below leaf litter in south-slope plots during controlled burns in the Ouachita Mountains of Arkansas to determine the probability of survival. Maximum temperature recorded under leaf litter averaged 292 degrees Celsius (558 degrees Fahrenheit). Only 5 percent of the plots experienced temperatures that were deemed survivable (less than 60 degrees Celsius or less than 140 degrees Fahrenheit) during burns on warmer winter days. Temperatures below the leaf litter measured just before the arrival of fire (about 19.6 degrees Celsius or 67.28 degrees Fahrenheit) suggested that if bats were roosting in plots they would have been in shallow torpor, which would have enabled faster escape from approaching flames. Burning during the warmer periods of winter, greater or equal to 15 degrees Celsius (59 degrees Fahrenheit) and during afternoons could potentially improve survival by bats roosting under leaf litter by reducing arousal and escape times.
|Temperatures below leaf litter during winter prescribed burns: implications for litter-roosting bats||(publication)|