Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland
Breiðafjörður Bay, West Iceland, is an important breeding, molting and wintering area for the Common Eider (Somateria mollissima) (hereafter Eider). Eider farmers have collected nest down for centuries in the area. The aims of the doctoral thesis centered on feeding and breeding ecology of Eiders in...
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Online Access: | http://hdl.handle.net/1946/25681 |
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ftskemman:oai:skemman.is:1946/25681 2023-05-15T15:46:29+02:00 Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland Varpvistfræði æðarfugls (Somateria mollissima) við Breiðafjörð. Þórður Örn Kristjánsson 1981- Háskóli Íslands 2016-09 application/pdf http://hdl.handle.net/1946/25681 en eng http://hdl.handle.net/1946/25681 Líffræði Thesis Doctoral 2016 ftskemman 2022-12-11T06:58:02Z Breiðafjörður Bay, West Iceland, is an important breeding, molting and wintering area for the Common Eider (Somateria mollissima) (hereafter Eider). Eider farmers have collected nest down for centuries in the area. The aims of the doctoral thesis centered on feeding and breeding ecology of Eiders in Breiðafjörður. The incubation behavior in a very dense colony (Rif, 1.7 nests/m2) was studied to evaluate whether the incubating females helped each other through the incubation by attending more than one nest. Incubation cost was indexed with mass loss of the females during the incubation period and was compared between nests with and without down removal, and between females with enlarged clutches (≥7 eggs) and those incubating normal clutches (≤6 egg). Ectoparasites were collected from the Eider nests and abundances of the flea (Cerotophyllus garei) was compared between two colonies at Rif and Hvallátur. The spring/early summer (May-July) diet of the Eiders was investigated between years, months and sexes. Cooperative incubation behavior was confirmed with marked Eiders in the superdense colony at Rif. The females attended each other‘s nests, which may be a behavioral response to lack of new nesting sites and visual stimulus as they see many unguarded nests close to their own. Eiders at Rif might own some eggs in more than one nest in the colony. The ectoparasitic load at Rif is very high and the cooperative behavior gives the incubating females more time to leave their nests to preen while other Eiders attend their nests. At the more sparsely-nested colony at Hvallátur cooperative incubation has never been observed but there Eiders can switch nesting bowls between years if ectoparasitic loads become high. The key food item in spring/early summer feeding was the mottled red chiton (Tonicella marmorea). Chitons have not been considered an important food item for Eiders until now. Down collection was not found to have effect on the incubating Eiders, during these average weather conditions. Likewise, the enlarged ... Doctoral or Postdoctoral Thesis Breiðafjörður Common Eider Iceland Somateria mollissima Skemman (Iceland) Rif ENVELOPE(-16.172,-16.172,66.526,66.526) Breiðafjörður ENVELOPE(-23.219,-23.219,65.253,65.253) Hvallátur ENVELOPE(-22.761,-22.761,65.421,65.421) |
institution |
Open Polar |
collection |
Skemman (Iceland) |
op_collection_id |
ftskemman |
language |
English |
topic |
Líffræði |
spellingShingle |
Líffræði Þórður Örn Kristjánsson 1981- Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland |
topic_facet |
Líffræði |
description |
Breiðafjörður Bay, West Iceland, is an important breeding, molting and wintering area for the Common Eider (Somateria mollissima) (hereafter Eider). Eider farmers have collected nest down for centuries in the area. The aims of the doctoral thesis centered on feeding and breeding ecology of Eiders in Breiðafjörður. The incubation behavior in a very dense colony (Rif, 1.7 nests/m2) was studied to evaluate whether the incubating females helped each other through the incubation by attending more than one nest. Incubation cost was indexed with mass loss of the females during the incubation period and was compared between nests with and without down removal, and between females with enlarged clutches (≥7 eggs) and those incubating normal clutches (≤6 egg). Ectoparasites were collected from the Eider nests and abundances of the flea (Cerotophyllus garei) was compared between two colonies at Rif and Hvallátur. The spring/early summer (May-July) diet of the Eiders was investigated between years, months and sexes. Cooperative incubation behavior was confirmed with marked Eiders in the superdense colony at Rif. The females attended each other‘s nests, which may be a behavioral response to lack of new nesting sites and visual stimulus as they see many unguarded nests close to their own. Eiders at Rif might own some eggs in more than one nest in the colony. The ectoparasitic load at Rif is very high and the cooperative behavior gives the incubating females more time to leave their nests to preen while other Eiders attend their nests. At the more sparsely-nested colony at Hvallátur cooperative incubation has never been observed but there Eiders can switch nesting bowls between years if ectoparasitic loads become high. The key food item in spring/early summer feeding was the mottled red chiton (Tonicella marmorea). Chitons have not been considered an important food item for Eiders until now. Down collection was not found to have effect on the incubating Eiders, during these average weather conditions. Likewise, the enlarged ... |
author2 |
Háskóli Íslands |
format |
Doctoral or Postdoctoral Thesis |
author |
Þórður Örn Kristjánsson 1981- |
author_facet |
Þórður Örn Kristjánsson 1981- |
author_sort |
Þórður Örn Kristjánsson 1981- |
title |
Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland |
title_short |
Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland |
title_full |
Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland |
title_fullStr |
Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland |
title_full_unstemmed |
Breeding ecology of the Common Eider (Somateria mollissima) in Breiðafjörður, West Iceland |
title_sort |
breeding ecology of the common eider (somateria mollissima) in breiðafjörður, west iceland |
publishDate |
2016 |
url |
http://hdl.handle.net/1946/25681 |
long_lat |
ENVELOPE(-16.172,-16.172,66.526,66.526) ENVELOPE(-23.219,-23.219,65.253,65.253) ENVELOPE(-22.761,-22.761,65.421,65.421) |
geographic |
Rif Breiðafjörður Hvallátur |
geographic_facet |
Rif Breiðafjörður Hvallátur |
genre |
Breiðafjörður Common Eider Iceland Somateria mollissima |
genre_facet |
Breiðafjörður Common Eider Iceland Somateria mollissima |
op_relation |
http://hdl.handle.net/1946/25681 |
_version_ |
1766381175297802240 |