A new paper, published in the Wildlife Society Bulletin, documents only the second known instance of a North American bat singing. Based on recordings made outside two old mine sites used by silver-haired bats in British Columbia and a scattering of forest locations in western North America, researchers have concluded that these bats use sounds for more than echolocation or simple social calls.
This is a timely finding as silver-haired singing provides a useful way to distinguish this species from other bats that use similar echolocation calls, such as big brown bats and hoary bats. Both the hoary and silver-haired bats are migratory species, which are experiencing heavy mortality from wind power development. Both have been recently assessed by COSEWIC (Committee on Status of Endangered Wildlife in Canada) as Endangered. Conversely, big brown bats are one of the few Canadian bat species that is not considered at risk anywhere in Canada.
Being able to accurately determine which species are present in the area of existing or potential wind power developments can help with mitigation and monitoring. Being able to conclusively differentiate bat species using bat detectors only, without requiring capture, is a welcome species conservation tool at a time when wind energy development is poised to exponentially increase.
Resources: Sound file (mp3) recordings of bat singing and with a mix of singing and social calls.
Photo credits: Banner | William Halliday © WCS Canada