Overwinter thermal habitat use in lakes by anadromous Arctic char

Anadromous Arctic char (Salvelinus alpinus) migrate back to fresh water in late summer to spawn and (or) overwinter. Upon freshwater entry, feeding is reduced or absent, and movement activity is restricted. While the physiological responses to low temperatures (e.g., growth, metabolism) are understo...

Full description

Saved in:
Bibliographic Details
Published in:Canadian journal of fisheries and aquatic sciences 2018, Vol.75 (12), p.2343-2353
Main Authors: Mulder, Ingeborg M., Morris, Corey J., Dempson, J. Brian, Fleming, Ian A., Power, Michael
Format: Article
Language:English
Subjects:
Acoustic data
Acoustic telemetry
Anadromous species
Body temperature
Energy costs
Energy expenditure
Feeders
Feeding
Feeding habits
Fish
Foraging habitats
Fresh water
Freshwater
Freshwater environments
Habitat utilization
Habitats
Ice cover
Lakes
Lipid metabolism
Lipids
Local movements
Low temperature
Metabolism
Migration
Migrations
Overwintering
Physiological responses
Prey
Salvelinus alpinus
Seasonal distribution
Spawning grounds
Spawning migrations
Summer
Telemetry
Thermal stratification
Thermoregulation
Water column
Water temperature
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Anadromous Arctic char (Salvelinus alpinus) migrate back to fresh water in late summer to spawn and (or) overwinter. Upon freshwater entry, feeding is reduced or absent, and movement activity is restricted. While the physiological responses to low temperatures (e.g., growth, metabolism) are understood, specifics of the use of thermal habitat for overwintering remains poorly characterized. This study used acoustic and archival telemetry data from two lakes in southern Labrador, Canada, to study thermal habitat use during the ice-covered period. Results showed that lake-dwelling anadromous Arctic char predominantly occupied a narrow range of temperatures (0.5–2 °C) and used cooler temperatures available within the middle and upper water column. Use of the selected temperatures is likely a strategy that lowers metabolic costs and minimizes energy expenditure, preserving stored lipids for overwinter survival and the energetic costs of preparation for seaward migration. As Arctic char are visual feeders, use of the upper water column is also thought to aid foraging efficiency by increasing the likelihood of prey capture.
ISSN:0706-652X
1205-7533
DOI:10.1139/cjfas-2017-0420