PARENT SESSION
Poster Session 25: Mammalian Ecology
Thursday, August 11, 5:00 PM - 6:30 PM, Exhibit Hall 220 A-E, Level 2, Palais des congrès de Montréal

Bat-habitat relationships along an urban to forested landscape gradient.

Cote, Fabienne ^{*,1, 2}, Delorme, Michel³, Gagnon, Daniel^{1, 2}, ¹ Université du Quebec a Montreal, Montreal, Quebec, Canada² Groupe de recherche en ecologie forestiere interuniversitere, Montreal, Quebec, Canada³ Biodome de Montreal, Montreal, Quebec, Canada

ABSTRACT- In Québec (Canada), four out of eight species of bats have been listed as potentially threatened or vulnerable. Few studies have addressed their habitat use. The Montréal Biodôme and the Ministère des Ressources naturelles de la Faune et des Parcs du Québec have established a network of bat monitoring circuits in which volunteers have gathered data using ultrasonic detectors since 2000. We used the data to analyze bat species distribution in relation to habitat structure, during feeding and flight. Three regions representing a gradient across urban (Laval), agricultural (Eastern Townships) and mostly forested (Mauricie) landscapes were studied. Results show that Myotis species are abundant in Eastern Townships (45% of all calls) and Mauricie (65%), but almost absent in Laval (0.5%). In Laval, big brown bats are most common (58%). Tests show that there are often no significant differences in the location of bats along the monitoring circuits from year to year. Bat-habitat relationships were studied at different scales. We used three sizes of buffer zones for analyses (50 m, 100 m and 200 m diameter). In Mauricie (largely forested), there is a positive relationship between the occurrence of Myotis species and big brown bats and the presence of white streetlamps (200 m diameter buffer zones). White streetlamps have also a positive effect on Myotis species occurrence in the agricultural landscape. In the same region, bridges positively influence the occurrence of Myotis species and hoary bats (100 m diameter buffer zones). In the urban region, big brown bat, silver bat and hoary bat presence is negatively related to the abundance of structures such as roads, houses and large buildings but the influence of each variable changes depending on the scale of analysis. Overall, our study shows that some specific habitat structures favour bat activity while others do not. We also found that the relationships are not detectable at all spatial scales.

Key words: bats, habitat