Seasonal Microhabitat Selection and Use of Syntopic Populations of Lithobates okaloosae and Lithobates clamitans clamitans

Thomas A. Gorman, Carola A. Haas
2011 Journal of Herpetology  
Quantifying and comparing habitat selection of related, syntopic species may help elucidate how species partition resources and compete. The Florida Bog Frog (Lithobates okaloosae) is endemic to northwestern Florida and is syntopic with the more widely distributed Bronze Frog (Lithobates clamitans clamitans). Our objective was to determine whether these closely related frogs selected different microhabitat characteristics at male calling sites, which in turn may influence successful
more » ... cessful reproduction or survival. From 2006 to 2008, we quantified microhabitat characteristics of male calling sites used by both species on Eglin Air Force Base, Florida. We created a suite of a priori models and used paired logistic regression to assess each species' habitat selection. Further, we compared habitat characteristics from each species' most highly supported model to directly compare habitat use. Model selection indicated that calling sites for L. okaloosae were best described by habitat features related to microhabitat cover (i.e., submergent vegetation, emergent vegetation, woody debris, frog-level canopy cover, distance to cover), whereas L. c. clamitans selected sites based on features that may be favorable for female oviposition or egg development (i.e., depth, water movement, depth 3 water movement interaction). Further, L. c. clamitans selected sites with 3.7 times less submergent vegetation and 1.6 times greater water depths than L. okaloosae. At this scale, these ranids select microhabitat differently; however, there is overlap among some selected variables. The habitat characteristics used by L. okaloosae may be associated with fire in the uplands and occasionally in the wetlands.
doi:10.1670/10-135.1 fatcat:zulzxytd6fdsxcnziobrwldrva