EGG DEPOSITION PATTERNS USE IN REPSONSE TO ABIOTIC GRADIENTS

Beth Sabo; Sonoma State University, Swaim Biological Inc.; beth.sabo@sonoma.edu; David G. Cook, Derek Girman, PhD

In the Pacific Northwest region of North America, precipitation is predicted to be reduced by climate change (Maurer & Duffy 2005), with trends toward fewer, more extreme rainfall events in the winter and longer, drier, hotter summers (Flint & Flint 2012, Mallakpour 2018). Landscapes in mountainous regions are more vulnerable to these climactic perturbations, as they lose water at higher rates and require more rainfall to replenish groundwater stores in steep terrain (Flint et al 2018). With less water, first order streams are at risk of transforming into a series of intermittent pools (Bogan et al 2019). This has the potential to completely alter the form and function of the stream environment on which amphibian egg and larvae development depend. While much is known about the life histories of terrestrial adult lotic-breeding amphibians, much less is known about their egg and larval phases; those that are completely dependent on the quantity and quality of rainfall and associated streamflow. This study strives to understand at potential small-scale habitat associations between abiotic factors including meso- and micro-habitat structure, substrate type, flow rate, water depth, canopy closure, dissolved oxygen, water temperature and observations of egg mass deposition locations and larvael habitat use by foothill yellow-legged frog (Rana boylii) and red-belied newt (Tarciha rivularis). 

Poster Session   Student Paper