Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population
Copepods of the genus Calanus have adapted to high levels of seasonality in prey availability by entering a period of hibernation during winter known as diapause, but repeated observations of active Calanus spp. have been made in January in high latitude fjords which suggests plasticity in over-wint...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2020-09-01
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| Series: | Frontiers in Marine Science |
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| Online Access: | https://www.frontiersin.org/article/10.3389/fmars.2020.541564/full |
| _version_ | 1818380780931383296 |
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| author | Laura Hobbs Laura Hobbs Neil S. Banas Finlo R. Cottier Finlo R. Cottier Jørgen Berge Jørgen Berge Jørgen Berge Malin Daase |
| author_facet | Laura Hobbs Laura Hobbs Neil S. Banas Finlo R. Cottier Finlo R. Cottier Jørgen Berge Jørgen Berge Jørgen Berge Malin Daase |
| author_sort | Laura Hobbs |
| collection | DOAJ |
| description | Copepods of the genus Calanus have adapted to high levels of seasonality in prey availability by entering a period of hibernation during winter known as diapause, but repeated observations of active Calanus spp. have been made in January in high latitude fjords which suggests plasticity in over-wintering strategies. During the last decade, the period of Polar Night has been studied intensively in the Arctic. A continuous presence of an active microbial food web suggests the prevalence of low-level alternative copepod prey (such as microzooplankton) throughout this period of darkness. Here we provide further evidence of mid-winter zooplankton activity using a decadal record of moored acoustics from Kongsfjorden, Svalbard. We apply an individual based life-history model to investigate the fitness consequences of a range of over-wintering strategies (in terms of diapause timing and duration) under a variety of prey availability scenarios. In scenarios of no winter prey availability (Pwin=0μgCL-1), the optimal time to exit diapause is in March. However, as Pwin increases (up to 40μgCL−1), there is little fitness difference in copepods exiting diapause in January compared to March. From this, we suggest that Calanus are able (in energetic terms) to either i) exit diapause early to deal with uncertainty in spring bloom timing, or ii) remain active throughout winter if diapause is not possible (i.e., environment not deep enough, or not enough lipid reserves built up over the previous summer). The range of viable overwintering strategies increases with increasing Pwin, suggesting that there is more flexibility for Calanus spp. in a scenario of non-zero Pwin. |
| first_indexed | 2024-12-14T02:24:08Z |
| format | Article |
| id | doaj.art-e7f3e43700de4b0b9a62a42409102c05 |
| institution | Directory Open Access Journal |
| issn | 2296-7745 |
| language | English |
| last_indexed | 2024-12-14T02:24:08Z |
| publishDate | 2020-09-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Marine Science |
| spelling | doaj.art-e7f3e43700de4b0b9a62a42409102c052022-12-21T23:20:25ZengFrontiers Media S.A.Frontiers in Marine Science2296-77452020-09-01710.3389/fmars.2020.541564541564Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus PopulationLaura Hobbs0Laura Hobbs1Neil S. Banas2Finlo R. Cottier3Finlo R. Cottier4Jørgen Berge5Jørgen Berge6Jørgen Berge7Malin Daase8Department of Mathematics and Statistics, University of Strathclyde, Glasgow, United KingdomScottish Association for Marine Science, Oban, United KingdomDepartment of Mathematics and Statistics, University of Strathclyde, Glasgow, United KingdomDepartment of Mathematics and Statistics, University of Strathclyde, Glasgow, United KingdomDepartment for Arctic and Marine Biology, Faculty for Biosciences, Fisheries and Economics, UiT the Arctic University of Norway, Tromsø, NorwayDepartment for Arctic and Marine Biology, Faculty for Biosciences, Fisheries and Economics, UiT the Arctic University of Norway, Tromsø, NorwayDepartment of Arctic Biology, University Centre on Svalbard, Longyearbyen, NorwayDepartment of Biology, Centre for Autonomous Marine Operations and Systems, Norwegian University of Science and Technology, NTNU, Trondheim, NorwayDepartment for Arctic and Marine Biology, Faculty for Biosciences, Fisheries and Economics, UiT the Arctic University of Norway, Tromsø, NorwayCopepods of the genus Calanus have adapted to high levels of seasonality in prey availability by entering a period of hibernation during winter known as diapause, but repeated observations of active Calanus spp. have been made in January in high latitude fjords which suggests plasticity in over-wintering strategies. During the last decade, the period of Polar Night has been studied intensively in the Arctic. A continuous presence of an active microbial food web suggests the prevalence of low-level alternative copepod prey (such as microzooplankton) throughout this period of darkness. Here we provide further evidence of mid-winter zooplankton activity using a decadal record of moored acoustics from Kongsfjorden, Svalbard. We apply an individual based life-history model to investigate the fitness consequences of a range of over-wintering strategies (in terms of diapause timing and duration) under a variety of prey availability scenarios. In scenarios of no winter prey availability (Pwin=0μgCL-1), the optimal time to exit diapause is in March. However, as Pwin increases (up to 40μgCL−1), there is little fitness difference in copepods exiting diapause in January compared to March. From this, we suggest that Calanus are able (in energetic terms) to either i) exit diapause early to deal with uncertainty in spring bloom timing, or ii) remain active throughout winter if diapause is not possible (i.e., environment not deep enough, or not enough lipid reserves built up over the previous summer). The range of viable overwintering strategies increases with increasing Pwin, suggesting that there is more flexibility for Calanus spp. in a scenario of non-zero Pwin.https://www.frontiersin.org/article/10.3389/fmars.2020.541564/fullzooplanktonarcticlife-historyphenologycalanuscopepod |
| spellingShingle | Laura Hobbs Laura Hobbs Neil S. Banas Finlo R. Cottier Finlo R. Cottier Jørgen Berge Jørgen Berge Jørgen Berge Malin Daase Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population Frontiers in Marine Science zooplankton arctic life-history phenology calanus copepod |
| title | Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population |
| title_full | Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population |
| title_fullStr | Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population |
| title_full_unstemmed | Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population |
| title_short | Eat or Sleep: Availability of Winter Prey Explains Mid-Winter and Spring Activity in an Arctic Calanus Population |
| title_sort | eat or sleep availability of winter prey explains mid winter and spring activity in an arctic calanus population |
| topic | zooplankton arctic life-history phenology calanus copepod |
| url | https://www.frontiersin.org/article/10.3389/fmars.2020.541564/full |
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