Trophic ecology of Arctic char (Salvelinus alpinus L.) in the Cumberland Sound region of the Canadian Arctic

• Main Author: Ulrich, Kendra L.
• Other Authors: Tallman, Ross F. (Biological Sciences), Davoren, Gail (Biological Sciences) Docker, Margaret (Biological Sciences) Fisk, Aaron (Biological Sciences) Hanson, Mark (Environment and Geography)
• Format: Master Thesis
• Language: English
• Published: 2013
• Subjects: Arctic char; ecotype; trophic ecology; capelin; stable isotopes; fatty acids; Arctic; Cumberland Sound; Climate change; Salvelinus alpinus; Zooplankton
• Online Access: http://hdl.handle.net/1993/21693

Trophic ecology is a key component in describing patterns of variation between and within populations, particularly in Arctic marine systems wherein climate change is impacting food webs. This thesis investigates the trophic ecology of Arctic char (Salvelinus alpinus) in the Cumberland Sound region using a multi-indicator approach. My data show trophic niche differences between resident and anadromous ecotypes and evidence for estuarine feeding by residents. I document a shift in the marine diet of Arctic char from zooplankton to capelin (Mallotus villosus) – a novel prey species in this region – that has occurred in less than a decade. Changes in Arctic char growth imply population-level effects of this shift; however, more research is required. Finally, I find lipid effects on δ13C and lipid-extraction effects on δ15N and δ34S for Arctic char muscle tissue. Lipid-correction models did not provide adequate δ13C estimates; thus, chemical extraction or ecotype-specific validation of models is recommended. October 2013