Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators?
During winter, stream fishes are vulnerable to semi-aquatic predators like mammals and birds and reduce encounters by being active in darkness or under surface ice. Less is known about the behavior of fishes towards instream piscivorous fishes. Here, we examined how surface ice and light affected th...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-10-01
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| Series: | Fishes |
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| Online Access: | https://www.mdpi.com/2410-3888/8/10/521 |
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| author | Karl Filipsson Veronika Åsman Larry Greenberg Martin Österling Johan Watz Eva Bergman |
| author_facet | Karl Filipsson Veronika Åsman Larry Greenberg Martin Österling Johan Watz Eva Bergman |
| author_sort | Karl Filipsson |
| collection | DOAJ |
| description | During winter, stream fishes are vulnerable to semi-aquatic predators like mammals and birds and reduce encounters by being active in darkness or under surface ice. Less is known about the behavior of fishes towards instream piscivorous fishes. Here, we examined how surface ice and light affected the anti-predator behavior of juvenile brown trout (<i>Salmo trutta</i> Linnaeus, 1758) in relation to piscivorous burbot (<i>Lota lota</i> Linnaeus, 1758) and northern pike (<i>Esox lucius</i> Linnaeus, 1758) at 4 °C in experimental flumes. Trout had lower foraging and swimming activity and spent more time sheltering when predators were present than when absent. In daylight, trout’s swimming activity was not affected by predators, whereas in darkness trout were less active when predators were present. Trout consumed more drifting prey during the day when ice was present, and they positioned themselves further upstream when under ice cover, regardless of light conditions. Trout stayed closer to conspecifics under ice, but only in the presence of pike. Piscivorous fishes thus constitute an essential part of the predatory landscape of juvenile trout in winter, and thus loss of ice cover caused by climate warming will likely affect trout’s interactions with predators. |
| first_indexed | 2024-03-10T21:15:18Z |
| format | Article |
| id | doaj.art-0bab28ebb5df454c997ed6b7495c56a7 |
| institution | Directory Open Access Journal |
| issn | 2410-3888 |
| language | English |
| last_indexed | 2024-03-10T21:15:18Z |
| publishDate | 2023-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Fishes |
| spelling | doaj.art-0bab28ebb5df454c997ed6b7495c56a72023-11-19T16:28:09ZengMDPI AGFishes2410-38882023-10-0181052110.3390/fishes8100521Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators?Karl Filipsson0Veronika Åsman1Larry Greenberg2Martin Österling3Johan Watz4Eva Bergman5River Ecology and Management, Department of Environmental and Life Sciences, Karlstad University, Universitetsgatan 2, SE-651 88 Karlstad, SwedenRiver Ecology and Management, Department of Environmental and Life Sciences, Karlstad University, Universitetsgatan 2, SE-651 88 Karlstad, SwedenRiver Ecology and Management, Department of Environmental and Life Sciences, Karlstad University, Universitetsgatan 2, SE-651 88 Karlstad, SwedenRiver Ecology and Management, Department of Environmental and Life Sciences, Karlstad University, Universitetsgatan 2, SE-651 88 Karlstad, SwedenRiver Ecology and Management, Department of Environmental and Life Sciences, Karlstad University, Universitetsgatan 2, SE-651 88 Karlstad, SwedenRiver Ecology and Management, Department of Environmental and Life Sciences, Karlstad University, Universitetsgatan 2, SE-651 88 Karlstad, SwedenDuring winter, stream fishes are vulnerable to semi-aquatic predators like mammals and birds and reduce encounters by being active in darkness or under surface ice. Less is known about the behavior of fishes towards instream piscivorous fishes. Here, we examined how surface ice and light affected the anti-predator behavior of juvenile brown trout (<i>Salmo trutta</i> Linnaeus, 1758) in relation to piscivorous burbot (<i>Lota lota</i> Linnaeus, 1758) and northern pike (<i>Esox lucius</i> Linnaeus, 1758) at 4 °C in experimental flumes. Trout had lower foraging and swimming activity and spent more time sheltering when predators were present than when absent. In daylight, trout’s swimming activity was not affected by predators, whereas in darkness trout were less active when predators were present. Trout consumed more drifting prey during the day when ice was present, and they positioned themselves further upstream when under ice cover, regardless of light conditions. Trout stayed closer to conspecifics under ice, but only in the presence of pike. Piscivorous fishes thus constitute an essential part of the predatory landscape of juvenile trout in winter, and thus loss of ice cover caused by climate warming will likely affect trout’s interactions with predators.https://www.mdpi.com/2410-3888/8/10/521anti-predatorglobal changerdiel behaviorforagingpiscivorespredators |
| spellingShingle | Karl Filipsson Veronika Åsman Larry Greenberg Martin Österling Johan Watz Eva Bergman Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators? Fishes anti-predator global changer diel behavior foraging piscivores predators |
| title | Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators? |
| title_full | Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators? |
| title_fullStr | Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators? |
| title_full_unstemmed | Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators? |
| title_short | Winter Behavior of Juvenile Brown Trout in a Changing Climate: How Do Light and Ice Cover Affect Encounters with Instream Predators? |
| title_sort | winter behavior of juvenile brown trout in a changing climate how do light and ice cover affect encounters with instream predators |
| topic | anti-predator global changer diel behavior foraging piscivores predators |
| url | https://www.mdpi.com/2410-3888/8/10/521 |
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