Decline of the Northern Long-Eared Myotis (Myotis septentrionalis) in the Eastern Great Plains After the Arrival of White-Nose Syndrome

Abstract. The northern long-eared myotis (Myotis septentrionalis) has declined sharply in the eastern United States due to the disease white-nose syndrome (WNS), which is caused by the fungus Pseudogymnoascus destructans (Pd). However, less is known about the species' status in the central and western parts of its range where WNS has arrived more recently. Here we report the timing of the arrival of Pd and WNS to eastern Nebraska and examine acoustic and capture data of M. septentrionalis to determine the initial impact of the disease on this species. We sampled bats for the presence of Pd and WNS at several mines and one rock crevice in eastern Nebraska from 2014 to 2017. We also recorded bats with acoustic detectors and captured bats with mist nets in spring and summer from 2014 to 2019 at 2 forested sites along the Missouri River near areas of sampling for Pd/WNS. Both acoustic and capture data suggested that M. septentrionalis went from a common species in forests of eastern Nebraska to one that is encountered rarely after the arrival of WNS. Similar to the population declines in the eastern United States, our observations indicate that M. septentrionalis has also declined steeply in the eastern Great Plains and should be closely monitored in western parts of its distribution as WNS continues to spread.