The Influence of Body Size on Behavioral Thermal Preference in Atlantic Cod (Gadus morhua): Larger Fish Favor Colder Waters

• Published in: Fishes Vol. 8; no. 12; p. 596
• Main Authors: Schakmann, Mathias, Christensen, Emil Aputsiaq Flindt, Steffensen, John Fleng, Svendsen, Morten Bo Søndergaard
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.12.2023
• Subjects: Animal population; behavioral thermoregulation; Body size; Business metrics; Climate change; Cod; Conservation; Correlation; Distribution; ectothermy; Fish; Fish behavior; fish distribution; Fish populations; Gadus morhua; Geographical distribution; Global warming; Habitats; Hypotheses; Influence; Marine fishes; Metabolism; optimal temperature; Physical fitness; Physiology; Polar environments; Polar regions; Temperature; Temperature preferences; Whitefish
• ISSN: 2410-3888; 2410-3888
• DOI: 10.3390/fishes8120596

In the context of global warming and the concurrent decrease in ectothermic fish body size, the mechanisms driving this phenomenon remain a subject of scientific debate. This study, utilizing the Atlantic cod (Gadus morhua) as a model organism, delves into the behavioral size-dependent temperature preference in the context of climate change. A significant negative correlation between temperature preference and fish size was discovered, aligning with in situ habitat temperatures and optimal physiological performance metrics from other studies. This correlation suggests that larger fish exhibit a behavioral preference for colder areas, potentially leading to shifts in distribution toward polar regions or deeper waters in response to local global warming. The findings contribute to predictions of species distribution shifts, emphasizing the critical role of size-dependent temperature preference in shaping fish populations and offering valuable insights for conservation efforts. Additionally, the study uncovers a noteworthy relationship between body size and thermal safety margins in fish behavior, providing a novel avenue for future research into the intricate dynamics of thermal regulation in response to climate change. Overall, this research enhances our understanding of the complex interplay between temperature, fish size, and ecological responses, offering crucial information for informed conservation and management strategies.