PARENT SESSION
Contributed Oral Session 17: Reptiles and Amphibians: Habitat; and Communities
Monday, August 8, 8:00 AM - 11:30 AM, Meeting Room 524 B, Level 5, Palais des congrès de Montréal
Wood frog (Rana sylvatica) and spotted salamander (Ambystoma maculatum) egg mass abundances in relation to landscape, basin and micro-site characteristics.
Boorse, Dorothy1, Camp, Ed1, Hamel, Laura 1, Kerry, Jennifer1, Daya, William 1, Matthieson, Cliff1, 1 Gordon College, Wenham, MA, USA
ABSTRACT- College Wood frogs (Rana sylvatica) and spotted salamanders (Ambystoma maculatum) are vernal pool species; their presence is one criterion that allows vernal pool certification. Vernal pools are usually basin-shaped, with steep sides and isolated from other water bodies. However, some areas that have obligate species are large, flatter areas more similar to floodplains for intermittent streams, or seem to be the edges of other wetland areas. We hypothesized that the basin shape would determine some of the habitat value for obligate species. Water quality also varies between vernal pools. In springs 2003, 2004 and 2005, in 18 vernal pools on protected land, we censused the number of egg masses laid by wood frogs and spotted salamanders in six floodplain and twelve basin-shaped vernal pools. We found a combination of landscape, basin and within-basin microsite characteristics determined breeding effort for these two species. Basin shape affected wood frog but not spotted salamander egg mass distribution. With the exception of conductivity, selected water quality measures did not affect egg mass distribution. Because larger floodplain wetlands are more likely to be protected by law, small pools are more easily degraded or destroyed. Landscape characteristics determine proximity of isolated wetlands to immigrants, upland habitat and thus combine with basin shape and water quality to affect breeding effort choice. Salamander egg masses were found within 3 m of shoreline in large pools. Thus large protected areas may be less used as breeding sites and when used, may have large unuseable areas. Preferential protection of large contiguous wetland areas may leave some valuable vernal pools unprotected and overestimate breeding site availability to both wood frogs and spotted salamanders.
Key words: vernal pool, egg mass, Rana sylvatica, Ambystoma maculatum