Climate-Induced Habitat Fragmentation Affects Metapopulation Structure of Arctic Grayling in Tundra Streams

• Main Author: Golden, Heidi E
• Format: Text
• Language: unknown
• Published: OpenCommons@UConn 2016
• Subjects: Climate change; Arctic grayling; connectivity; fragmentation; genetics; vital rates; metapopulation; Arctic; Thymallus arcticus; Tundra
• Online Access: https://opencommons.uconn.edu/dissertations/1259; https://opencommons.uconn.edu/cgi/viewcontent.cgi?article=7494&context=dissertations

Climate change is altering ecosystems across the globe, with ecological and evolutionary consequences affecting species persistence and biodiversity. I investigated the effects of changing hydrology on Arctic grayling (Thymallus arcticus) metapopulation structure, microgeographic differentiation, movement patterns and vital rates using neutral genetic microsatellite markers, remote sensing of PIT-tagged individuals, body condition and ovarian histology. Arctic grayling within the study area on Alaska’s North Slope comprised five distinct genetic clusters. River distance and dry zones were significant factors explaining genetic differentiation among locations. Migration was low and asymmetrical among genetic clusters, but higher from headwater populations to the large coastal population than contrariwise. Adult Arctic grayling spawning movement patterns strongly associated with microgeographic neutral genetic differentiation within two watersheds. Following drought, I found significant differences in fall movement patterns and subsequent increased mortality of detained versus non-detained fish. My research on Arctic grayling underscores the significance of maintaining habitat connectivity for metapopulation persistence and the importance of including connectivity in conservation and management models to help mitigate the effects of climate change on species extinctions.