Northern Red-legged Frog Terrestrial Movement and Connectivity in a Fragmented Peri-urban Landscape

The movement and spatial ecology of amphibians is largely understudied, despite their imperiled conservation status. Landscape fragmentation by roads and other anthropogenic development features are known to affect amphibians in multiple ways pertaining to movement, often leading to population declines and exacerbating extinction risk. To mitigate these factors, wildlife managers can implement multidisciplinary strategies that seek to preserve or restore functional connectivity. However, these efforts require strong fundamental knowledge of how a species interacts with complex landscapes throughout their life cycle, including through their movement.My thesis investigates multiple facets of northern red-legged frog (Rana aurora) spatial ecology by monitoring use of road crossing infrastructure and modeling landscape connectivity using species-specific empirical movement data. Using remote sensing technology, I describe R. aurora activity in a recently installed road undercrossing structure intended to mitigate road mortality for the species, and explore temperature, humidity, and precipitation as drivers of frog detection in the structure. Additionally, I document the post-breeding migrations of frogs at multiple focal sites with radio telemetry, and employ the resulting movement data as an independent validation of fine and coarse-resolution habitat connectivity models for the species in an urbanizing area of northwest Portland. Knowledge gained from this study will inform future amphibian-focused road crossing design and contribute to a developing understanding of habitat connectivity and amphibian movement in anthropogenically altered ecosystems.