The Office of Graduate Programs is pleased to announce that Cherie Mosher will be defending their dissertation entitled “Curious Case of the Coastal Tailed Frog (Ascaphus Truei) Near the Northern Extent of its Range” as a candidate for the degree Doctor of Philosophy in Natural Resources and Environmental Studies. We encourage you to view the defence online. The details on the defence and how to join are included below.
DATE: June 25, 2020
TIME: 1:00 PM
Meeting ID: 922 1562 8334
To ensure the defence proceeds with no interruptions, please mute your audio and video on entry and do not share your screen inadvertently. The meeting will be locked to entry 5 minutes after it begins, ensure you are on time.
ABSTRACT: Ascaphus truei, an ancient species of frog, migrated into British Columbia, Canada, following the last ice age. A. truei is of conservation interest because forestry practices, and the associated infrastructure, may reduce habitat quality. There is also concern that a warmer and drier climate will change the distribution and abundance of this species. I used two genetic methods, microsatellites and next-generation sequencing, to compare the genetic diversity of A. truei from the northern extent of its range in British Columbia to southern Washington, US. Both methods suggested a dramatic reduction in diversity across the northern portion of the species’ range. The phylogeography suggests a northern range expansion from a single refugium. I used DNA metabarcoding to compare the gut contents of larvae across three stream reaches and two development classes near the northern extent of A. truei's range. Gut contents differed between stream reach but did not differ between development class. Wetted width and ultimately stream volume may influence differences in gut content between stream reaches. I also quantified the relationship between an index of larvae density and
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