Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada
Anthropogenic influences and climate change are warming rivers in New Brunswick and threatening the cold water habitats of native salmonids. When ambient river temperatures in summer exceed the tolerance level of Atlantic salmon and brook trout, individuals behaviourally thermoregulate by seeking ou...
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Fredericton: University of New Brunswick
2012
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ftcanadathes:oai:collectionscanada.gc.ca:UNB.1882/35663 2023-05-15T15:30:41+02:00 Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada Wilbur, Nathan University of New Brunswick, Faculty of Engineering MacQuarrie, K. T. B. Curry, R. A. 2012-01-17T19:11:50Z http://hdl.handle.net/1882/35663 unknown Fredericton: University of New Brunswick http://hdl.handle.net/1882/35663 thermal refugia habitat preference thermal infrared imagery Atlantic Salmon brook trout Thesis or Dissertation 2012 ftcanadathes 2013-11-23T23:19:45Z Anthropogenic influences and climate change are warming rivers in New Brunswick and threatening the cold water habitats of native salmonids. When ambient river temperatures in summer exceed the tolerance level of Atlantic salmon and brook trout, individuals behaviourally thermoregulate by seeking out cold water refugia. These critical thermal habitats are often created by tributaries and concentrated groundwater discharge. Thermal infrared imagery was used to map cold water anomalies along a 53 km reach of the Cains River on 23 July 2008. Although efficient and useful for mapping surface temperature of a continuous stream reach, the fish did not use all identified thermal anomalies as refugia. Overall, 100 % of observed large brook trout >35 cm in length were found in 30 % of the TIR-mapped cold water anomalies. Ninety eight percent of observed small brook trout 8 – 30 cm in length were found in 80 % of the mapped cold water anomalies and their densities within anomalies were significantly higher than densities outside of anomalies. Fifty nine percent of observed salmon parr were found in 65 % of the mapped anomalies; however, they were dispersed within study sites and their densities were not significantly different within anomalies compared to outside of the anomalies. No brook trout were observed at the seven noncold water study sites that were investigated. Preference curves for various habitat variables including velocity, temperature, depth, substrate, and deep water availability near cold water anomalies were developed based on field investigations during high temperature events (ambient river temperature >21 oC). Combined with thermal imagery, managers can use the physical descriptions of thermal refugia developed here as a tool to help conserve and restore critical thermal refugia for Atlantic salmon and brook trout on the Cains River, and potentially similar river systems. Thesis Atlantic salmon Salmo salar Theses Canada/Thèses Canada (Library and Archives Canada) Canada |
institution |
Open Polar |
collection |
Theses Canada/Thèses Canada (Library and Archives Canada) |
op_collection_id |
ftcanadathes |
language |
unknown |
topic |
thermal refugia habitat preference thermal infrared imagery Atlantic Salmon brook trout |
spellingShingle |
thermal refugia habitat preference thermal infrared imagery Atlantic Salmon brook trout Wilbur, Nathan Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada |
topic_facet |
thermal refugia habitat preference thermal infrared imagery Atlantic Salmon brook trout |
description |
Anthropogenic influences and climate change are warming rivers in New Brunswick and threatening the cold water habitats of native salmonids. When ambient river temperatures in summer exceed the tolerance level of Atlantic salmon and brook trout, individuals behaviourally thermoregulate by seeking out cold water refugia. These critical thermal habitats are often created by tributaries and concentrated groundwater discharge. Thermal infrared imagery was used to map cold water anomalies along a 53 km reach of the Cains River on 23 July 2008. Although efficient and useful for mapping surface temperature of a continuous stream reach, the fish did not use all identified thermal anomalies as refugia. Overall, 100 % of observed large brook trout >35 cm in length were found in 30 % of the TIR-mapped cold water anomalies. Ninety eight percent of observed small brook trout 8 – 30 cm in length were found in 80 % of the mapped cold water anomalies and their densities within anomalies were significantly higher than densities outside of anomalies. Fifty nine percent of observed salmon parr were found in 65 % of the mapped anomalies; however, they were dispersed within study sites and their densities were not significantly different within anomalies compared to outside of the anomalies. No brook trout were observed at the seven noncold water study sites that were investigated. Preference curves for various habitat variables including velocity, temperature, depth, substrate, and deep water availability near cold water anomalies were developed based on field investigations during high temperature events (ambient river temperature >21 oC). Combined with thermal imagery, managers can use the physical descriptions of thermal refugia developed here as a tool to help conserve and restore critical thermal refugia for Atlantic salmon and brook trout on the Cains River, and potentially similar river systems. |
author2 |
University of New Brunswick, Faculty of Engineering MacQuarrie, K. T. B. Curry, R. A. |
format |
Thesis |
author |
Wilbur, Nathan |
author_facet |
Wilbur, Nathan |
author_sort |
Wilbur, Nathan |
title |
Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada |
title_short |
Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada |
title_full |
Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada |
title_fullStr |
Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada |
title_full_unstemmed |
Characterizing thermal refugia for brook trout (Salvelinus fontinalis) and Atlantic salmon (Salmo salar) in the Cains River, New Brunswick, Canada |
title_sort |
characterizing thermal refugia for brook trout (salvelinus fontinalis) and atlantic salmon (salmo salar) in the cains river, new brunswick, canada |
publisher |
Fredericton: University of New Brunswick |
publishDate |
2012 |
url |
http://hdl.handle.net/1882/35663 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
Atlantic salmon Salmo salar |
genre_facet |
Atlantic salmon Salmo salar |
op_relation |
http://hdl.handle.net/1882/35663 |
_version_ |
1766361136354033664 |