Earlier pupping in harbour seals, Phoca vitulina
The annual reproductive cycle of most seal species is characterized by a tight synchrony of births. Typically, timing of birth shows little inter-annual variation. Here, however we show that harbour seals Phoca vitulina from the Wadden Sea (southeast North Sea) have shortened their yearly cycle, mov...
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ftunivwagenin:oai:library.wur.nl:wurpubs/398277 2024-02-04T10:03:55+01:00 Earlier pupping in harbour seals, Phoca vitulina Reijnders, P.J.H. Brasseur, S.M.J.M. Meesters, H.W.G. 2010 application/pdf https://research.wur.nl/en/publications/earlier-pupping-in-harbour-seals-phoca-vitulina https://doi.org/10.1098/rsbl.2010.0468 en eng https://edepot.wur.nl/156840 https://research.wur.nl/en/publications/earlier-pupping-in-harbour-seals-phoca-vitulina doi:10.1098/rsbl.2010.0468 info:eu-repo/semantics/restrictedAccess Wageningen University & Research Biology Letters 6 (2010) 6 ISSN: 1744-9561 age fish community grey seals growth island long-term trends sex info:eu-repo/semantics/article Article/Letter to editor info:eu-repo/semantics/publishedVersion 2010 ftunivwagenin https://doi.org/10.1098/rsbl.2010.0468 2024-01-10T23:22:43Z The annual reproductive cycle of most seal species is characterized by a tight synchrony of births. Typically, timing of birth shows little inter-annual variation. Here, however we show that harbour seals Phoca vitulina from the Wadden Sea (southeast North Sea) have shortened their yearly cycle, moving parturition to earlier dates since the early 1970s. Between 1974 and 2009, the birth date of harbour seals shifted on average by -0.71 d yr-1, three and a half weeks (25 days) earlier, in the Dutch part of the Wadden Sea. Pup counts available for other parts of the Wadden Sea were analysed, showing a similar shift. To elucidate potential mechanism(s) for this shift in pupping phenology, possible changes in population demography, changes in maternal life-history traits and variations in environmental conditions were examined. It was deduced that the most likely mechanism was a shortening of embryonic diapause. We hypothesize that this could have been facilitated by an improved forage base, e.g. increase of small fishes, attributable to overfishing of large predator fishes and size-selective fisheries. Article in Journal/Newspaper Phoca vitulina Wageningen UR (University & Research Centre): Digital Library Biology Letters 6 6 854 857 |
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Open Polar |
collection |
Wageningen UR (University & Research Centre): Digital Library |
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ftunivwagenin |
language |
English |
topic |
age fish community grey seals growth island long-term trends sex |
spellingShingle |
age fish community grey seals growth island long-term trends sex Reijnders, P.J.H. Brasseur, S.M.J.M. Meesters, H.W.G. Earlier pupping in harbour seals, Phoca vitulina |
topic_facet |
age fish community grey seals growth island long-term trends sex |
description |
The annual reproductive cycle of most seal species is characterized by a tight synchrony of births. Typically, timing of birth shows little inter-annual variation. Here, however we show that harbour seals Phoca vitulina from the Wadden Sea (southeast North Sea) have shortened their yearly cycle, moving parturition to earlier dates since the early 1970s. Between 1974 and 2009, the birth date of harbour seals shifted on average by -0.71 d yr-1, three and a half weeks (25 days) earlier, in the Dutch part of the Wadden Sea. Pup counts available for other parts of the Wadden Sea were analysed, showing a similar shift. To elucidate potential mechanism(s) for this shift in pupping phenology, possible changes in population demography, changes in maternal life-history traits and variations in environmental conditions were examined. It was deduced that the most likely mechanism was a shortening of embryonic diapause. We hypothesize that this could have been facilitated by an improved forage base, e.g. increase of small fishes, attributable to overfishing of large predator fishes and size-selective fisheries. |
format |
Article in Journal/Newspaper |
author |
Reijnders, P.J.H. Brasseur, S.M.J.M. Meesters, H.W.G. |
author_facet |
Reijnders, P.J.H. Brasseur, S.M.J.M. Meesters, H.W.G. |
author_sort |
Reijnders, P.J.H. |
title |
Earlier pupping in harbour seals, Phoca vitulina |
title_short |
Earlier pupping in harbour seals, Phoca vitulina |
title_full |
Earlier pupping in harbour seals, Phoca vitulina |
title_fullStr |
Earlier pupping in harbour seals, Phoca vitulina |
title_full_unstemmed |
Earlier pupping in harbour seals, Phoca vitulina |
title_sort |
earlier pupping in harbour seals, phoca vitulina |
publishDate |
2010 |
url |
https://research.wur.nl/en/publications/earlier-pupping-in-harbour-seals-phoca-vitulina https://doi.org/10.1098/rsbl.2010.0468 |
genre |
Phoca vitulina |
genre_facet |
Phoca vitulina |
op_source |
Biology Letters 6 (2010) 6 ISSN: 1744-9561 |
op_relation |
https://edepot.wur.nl/156840 https://research.wur.nl/en/publications/earlier-pupping-in-harbour-seals-phoca-vitulina doi:10.1098/rsbl.2010.0468 |
op_rights |
info:eu-repo/semantics/restrictedAccess Wageningen University & Research |
op_doi |
https://doi.org/10.1098/rsbl.2010.0468 |
container_title |
Biology Letters |
container_volume |
6 |
container_issue |
6 |
container_start_page |
854 |
op_container_end_page |
857 |
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1789971755946737664 |