Investigating climate change impacts on Arctic Charr (Salvelinus alpinus) in Canada and the Circumpolar Region: environmental and species interactions

• Main Author: Kiernicki Bommersbach, Cassandra
• Other Authors: Walker, David (Environment and Geography), Long, Jeff (Manitoba Natural Resources and Northern Development), Deslauriers, David (Université du Québec à Rimouski), Tallman, Ross, Baydack, Rick
• Format: Master Thesis
• Language: English
• Published: 2023
• Subjects: Arctic Charr; Arctic; Canada; Arctic charr; Climate change; Salvelinus alpinus
• Online Access: http://hdl.handle.net/1993/37286

One of the greatest challenges for researchers today is understanding climate change impacts on fish populations, particularly in vulnerable ecosystems such as the Canadian Arctic. Northern fish populations will undergo thermal stress as atmospheric temperatures are projected to rise globally. Models that consider both environmental factors and species interactions can help project the future distribution of a species. This thesis investigates the climate change impacts of rising temperatures and the potential northward shift of Brook Trout (Salvelinus fontinalis) on Arctic Charr (Salvelinus alpinus), Canada’s highly valuable and northernmost fish species. Understanding the current distribution of Arctic Charr in Canada will help determine future projections based on warming temperatures and species interactions. A logistic regression model for Arctic Charr evaluated a baseline time period (1976-2005) using growing-degree day, longitude, latitude, and Brook Trout occurrences, correctly classified 93% of Arctic Charr occurrences in Canada. The distribution of Arctic Charr is projected to contract by 18% in Canada by the time period of 2051-2080 using a High Carbon scenario. The projected distributions only included known native populations of Arctic Charr and Brook Trout and excluded any deliberate or accidental human-induced introductions. The decrease in the projected distribution of Arctic Charr could be attributed to warming atmospheric temperatures that lengthen growing seasons in the Arctic. The Canadian high Arctic will provide refuge for Arctic Charr, where conservation efforts will need prioritizing. May 2023