Egg mass drift increases vulnerability during early development of Cascades frogs (Rana casadae).

Abstract

Many anuran species exhibit oviposition site selection. Female selection of oviposition sites may influence the success of offspring and increase overall fitness (Resetarits 1996). Egg mass placement (location and attachment substrate) may be determined by a number of factors including detectability by predators, water velocity, risk of desiccation or flooding, and temperature (Stebbins and Cohen 1997). Some lentic breeding anurans do not always attach their egg masses to substrates (Briggs 1987; Olson 2005; Reaser and Pilliod 2005; Wind 2005), making them vulnerable to involuntary displacement. The movement of egg masses to areas of sub-optimal conditions (for example, colder water or desiccation from stranding) may affect hatching success and overall survival of individuals (Licht 1971; Sype 1974). Here, we document high occurrences of egg mass displacement in a high-elevation breeding population of Rana cascadae (Cascades Frog).

Citation

Justin M. Garwood; Clara A. Wheeler; Ryan M. Bourque; Monty D. Larson; and Hartwell H. Welsh, Jr. 2007. Egg mass drift increases vulnerability during early development of Cascades frogs (Rana casadae). Northwestern Naturalist 88:95-97