Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators
The critical endangered Common and Brünnich guillemot are exhibiting contrasting population trends in the Barents Sea region, where the Common guillemots are increasing, while Brünnich guillemots are declining. The non-breeding season is regarded as the main mortality period among seabirds, especial...
Main Author: | |
---|---|
Format: | Master Thesis |
Language: | English |
Published: |
UiT Norges arktiske universitet
2022
|
Subjects: | |
Online Access: | https://hdl.handle.net/10037/24807 |
id |
ftunivtroemsoe:oai:munin.uit.no:10037/24807 |
---|---|
record_format |
openpolar |
spelling |
ftunivtroemsoe:oai:munin.uit.no:10037/24807 2023-05-15T15:38:32+02:00 Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators Nilssen, Kristina Emilie 2022-02-16 https://hdl.handle.net/10037/24807 eng eng UiT Norges arktiske universitet UiT The Arctic University of Norway https://hdl.handle.net/10037/24807 Copyright 2022 The Author(s) VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Økologi: 488 Geolocation stable isotopes guillemot murre Uria aalge Uria lomvia BIO-3950 Master thesis Mastergradsoppgave 2022 ftunivtroemsoe 2022-04-20T22:58:30Z The critical endangered Common and Brünnich guillemot are exhibiting contrasting population trends in the Barents Sea region, where the Common guillemots are increasing, while Brünnich guillemots are declining. The non-breeding season is regarded as the main mortality period among seabirds, especially in winter, as climate conditions may be harsh and prey availability rather limited. The contrasting trends seen in the Barents Sea Common and Brünnich guillemot populations are believed to be related to the two species different non-breeding ecology, although little is known about the bird’s ecology in this particular period, as the species are out at sea, unavailable for scientists. However, the development of light-weighted tracking equipment has made it possible following small migrating species, such as birds, throughout the entire year-cycle. In combination with stable isotopes, such methods can be used to investigate species ecology non-invasively. This study used combined feather stable isotopes and light-based geolocation data of the two sympatric seabird species to investigate intra- and interspecific dynamics in their non-breeding strategies (i.e., changes in foraging distribution and isotopic niche) in the Barents Sea. Differential responses were found between the species foraging distribution and isotopic niches, as they showed no overlap in isotopic niches when their distribution overlapped, and vice versa, which might indicate an avoidance mechanism for equal resource utilization during the non-breeding season. The species responded differently to limitations in food conditions in the Barents Sea during winter, as Common guillemot exhibited smaller degree of change in isotopic niches compared to the Brünnich guillemot, indicating that the Brünnich guillemot change from having a generalized foraging strategy in winter, to become more specialized during autumn when food is more abundant. Master Thesis Barents Sea common guillemot Uria aalge Uria lomvia uria University of Tromsø: Munin Open Research Archive Barents Sea |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Økologi: 488 Geolocation stable isotopes guillemot murre Uria aalge Uria lomvia BIO-3950 |
spellingShingle |
VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Økologi: 488 Geolocation stable isotopes guillemot murre Uria aalge Uria lomvia BIO-3950 Nilssen, Kristina Emilie Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
topic_facet |
VDP::Mathematics and natural science: 400::Zoology and botany: 480::Ecology: 488 VDP::Matematikk og Naturvitenskap: 400::Zoologiske og botaniske fag: 480::Økologi: 488 Geolocation stable isotopes guillemot murre Uria aalge Uria lomvia BIO-3950 |
description |
The critical endangered Common and Brünnich guillemot are exhibiting contrasting population trends in the Barents Sea region, where the Common guillemots are increasing, while Brünnich guillemots are declining. The non-breeding season is regarded as the main mortality period among seabirds, especially in winter, as climate conditions may be harsh and prey availability rather limited. The contrasting trends seen in the Barents Sea Common and Brünnich guillemot populations are believed to be related to the two species different non-breeding ecology, although little is known about the bird’s ecology in this particular period, as the species are out at sea, unavailable for scientists. However, the development of light-weighted tracking equipment has made it possible following small migrating species, such as birds, throughout the entire year-cycle. In combination with stable isotopes, such methods can be used to investigate species ecology non-invasively. This study used combined feather stable isotopes and light-based geolocation data of the two sympatric seabird species to investigate intra- and interspecific dynamics in their non-breeding strategies (i.e., changes in foraging distribution and isotopic niche) in the Barents Sea. Differential responses were found between the species foraging distribution and isotopic niches, as they showed no overlap in isotopic niches when their distribution overlapped, and vice versa, which might indicate an avoidance mechanism for equal resource utilization during the non-breeding season. The species responded differently to limitations in food conditions in the Barents Sea during winter, as Common guillemot exhibited smaller degree of change in isotopic niches compared to the Brünnich guillemot, indicating that the Brünnich guillemot change from having a generalized foraging strategy in winter, to become more specialized during autumn when food is more abundant. |
format |
Master Thesis |
author |
Nilssen, Kristina Emilie |
author_facet |
Nilssen, Kristina Emilie |
author_sort |
Nilssen, Kristina Emilie |
title |
Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
title_short |
Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
title_full |
Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
title_fullStr |
Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
title_full_unstemmed |
Uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
title_sort |
uncovering the foraging strategies in two pelagic diving seabird species outside their breeding season using coupled feather stable isotopes and light-based geolocators |
publisher |
UiT Norges arktiske universitet |
publishDate |
2022 |
url |
https://hdl.handle.net/10037/24807 |
geographic |
Barents Sea |
geographic_facet |
Barents Sea |
genre |
Barents Sea common guillemot Uria aalge Uria lomvia uria |
genre_facet |
Barents Sea common guillemot Uria aalge Uria lomvia uria |
op_relation |
https://hdl.handle.net/10037/24807 |
op_rights |
Copyright 2022 The Author(s) |
_version_ |
1766369556032389120 |