Neal W Darby; Mojave National Preserve; neal_darby@nps.gov; Misumi B. Ogawa, Aren N. Calton, Carrie Gonzalas, Michael L. Morrison, Debra Hughson

Gallinaceous Guzzlers were widely established across the southwest beginning in the 1940s. Many of these structures still function but, degradation overtime and changes in jurisdictions and laws have complicated their management. For example, newly designated wilderness dictates their removal due to prohibited human structures. We implemented a Before/After Control Impact study to evaluate wildlife response to the loss of water from these guzzlers given the potential for removal. A subset of 14 guzzlers greater than 3.2 km from any other know water source were selected for monitoring. Seven were later selected for drainage of water (dewatering). Wildlife was monitored at the guzzlers using trail cameras and acoustic bat and bird recorders. Preliminary results suggest bats do not focus on guzzlers and were not affected by dewatering based on echolocation call detections. Of some 16 bird species detected on recorders at guzzlers, about half were detected on trial cameras at the guzzler mouth at regular intervals. Dewatering led to many birds that regularly visited the guzzler abandoning use of the guzzler. We are finalizing results of bird recordings taken after dewatering. Guzzlers likely benefit some species, but greater demographic data is needed to ascertain impacts of dewatering.

Mammals II: Bats  InPerson Presentation