"The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway"
Abstract In the recent decades large carnivores have started to recolonize former occupied areas in North America and in Europe. Increases in predator population sizes can affect the whole ecosystem functioning, but little work has been done on this area in Europe, especially when it comes to how sc...
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Online Access: | http://hdl.handle.net/10852/11728 http://urn.nb.no/URN:NBN:no-14010 |
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ftoslouniv:oai:www.duo.uio.no:10852/11728 2023-05-15T13:13:49+02:00 "The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" Gustavsen, Line Atle Mysterud (UIO), Arild Landa (NINA) 2006 http://hdl.handle.net/10852/11728 http://urn.nb.no/URN:NBN:no-14010 eng eng http://urn.nb.no/URN:NBN:no-14010 Gustavsen, Line. "The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway". Masteroppgave, University of Oslo, 2006 http://hdl.handle.net/10852/11728 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Gustavsen, Line&rft.title="The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway"&rft.inst=University of Oslo&rft.date=2006&rft.degree=Masteroppgave URN:NBN:no-14010 50488 070029385 Fulltext https://www.duo.uio.no/bitstream/handle/10852/11728/1/Masteroppgavex-xferdig.pdf økologi jerv rekolonisering ulv diett-analyse Sør-Norge VDP::488 Master thesis Masteroppgave 2006 ftoslouniv 2020-06-21T08:41:59Z Abstract In the recent decades large carnivores have started to recolonize former occupied areas in North America and in Europe. Increases in predator population sizes can affect the whole ecosystem functioning, but little work has been done on this area in Europe, especially when it comes to how scavengers are affected. The wolverine (Gulo gulo) is both a predator and a scavenger, and switches between this two roles. In this study, the wolverines’ diet was investigated in southern Norway based on scats found during winters in 2002 to 2004. My aim was to find out if recolonizing wolves (Canis lupus) might have changed the wolverines’ diet. I also investigated if there were sexual differences in diet in the wolverine population, and if diet varied annually and according to habitat. Moose (Alces alces) stood for 42.3% of the diet, reindeer (Rangifer tarandus) for 29.1% and small game (mainly rodents) for 29.7%. There was a broad structure in the data, and two axes were identified by Principal Component Analysis. The first axis (explaining 49.7% of the variation) was positively correlated with frequency of small game. The second axis (cumulative variance explained 91.7%) was strongly correlated with frequency of occurrence of small game that had been eaten and negatively correlated with the occurrence of both reindeer and (partly) moose that had been eaten. Before the re-colonization of wolves and recent increases in moose density, reindeer was the most important prey for the wolverine, but during the period of this study moose was the most important food source for the overall population. As predicted, the wolverines ate more moose inside than outside of wolf territories, indicating that wolves have increased the availability of moose carrions for wolverines. Females ate more small game than males, and males ate more big game than females. There were also annual variations in the diet but there were no marked variations between the different habitats apart from altitude. This study highlights how recolonization of carnivores can affect the diet of a scavenger by increasing the amount of carrions that are available, and thus change ecosystem functioning in northern habitats. Master Thesis Alces alces Canis lupus Gulo gulo Rangifer tarandus ulv Universitet i Oslo: Digitale utgivelser ved UiO (DUO) Norway |
institution |
Open Polar |
collection |
Universitet i Oslo: Digitale utgivelser ved UiO (DUO) |
op_collection_id |
ftoslouniv |
language |
English |
topic |
økologi jerv rekolonisering ulv diett-analyse Sør-Norge VDP::488 |
spellingShingle |
økologi jerv rekolonisering ulv diett-analyse Sør-Norge VDP::488 Gustavsen, Line "The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" |
topic_facet |
økologi jerv rekolonisering ulv diett-analyse Sør-Norge VDP::488 |
description |
Abstract In the recent decades large carnivores have started to recolonize former occupied areas in North America and in Europe. Increases in predator population sizes can affect the whole ecosystem functioning, but little work has been done on this area in Europe, especially when it comes to how scavengers are affected. The wolverine (Gulo gulo) is both a predator and a scavenger, and switches between this two roles. In this study, the wolverines’ diet was investigated in southern Norway based on scats found during winters in 2002 to 2004. My aim was to find out if recolonizing wolves (Canis lupus) might have changed the wolverines’ diet. I also investigated if there were sexual differences in diet in the wolverine population, and if diet varied annually and according to habitat. Moose (Alces alces) stood for 42.3% of the diet, reindeer (Rangifer tarandus) for 29.1% and small game (mainly rodents) for 29.7%. There was a broad structure in the data, and two axes were identified by Principal Component Analysis. The first axis (explaining 49.7% of the variation) was positively correlated with frequency of small game. The second axis (cumulative variance explained 91.7%) was strongly correlated with frequency of occurrence of small game that had been eaten and negatively correlated with the occurrence of both reindeer and (partly) moose that had been eaten. Before the re-colonization of wolves and recent increases in moose density, reindeer was the most important prey for the wolverine, but during the period of this study moose was the most important food source for the overall population. As predicted, the wolverines ate more moose inside than outside of wolf territories, indicating that wolves have increased the availability of moose carrions for wolverines. Females ate more small game than males, and males ate more big game than females. There were also annual variations in the diet but there were no marked variations between the different habitats apart from altitude. This study highlights how recolonization of carnivores can affect the diet of a scavenger by increasing the amount of carrions that are available, and thus change ecosystem functioning in northern habitats. |
author2 |
Atle Mysterud (UIO), Arild Landa (NINA) |
format |
Master Thesis |
author |
Gustavsen, Line |
author_facet |
Gustavsen, Line |
author_sort |
Gustavsen, Line |
title |
"The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" |
title_short |
"The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" |
title_full |
"The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" |
title_fullStr |
"The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" |
title_full_unstemmed |
"The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway" |
title_sort |
"the diet of a facultative scavenger, the wolverine (gulo gulo), after recolonization of wolf (canis lupus) in southern norway" |
publishDate |
2006 |
url |
http://hdl.handle.net/10852/11728 http://urn.nb.no/URN:NBN:no-14010 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Alces alces Canis lupus Gulo gulo Rangifer tarandus ulv |
genre_facet |
Alces alces Canis lupus Gulo gulo Rangifer tarandus ulv |
op_relation |
http://urn.nb.no/URN:NBN:no-14010 Gustavsen, Line. "The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway". Masteroppgave, University of Oslo, 2006 http://hdl.handle.net/10852/11728 info:ofi/fmt:kev:mtx:ctx&ctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft.au=Gustavsen, Line&rft.title="The diet of a facultative scavenger, the wolverine (Gulo gulo), after recolonization of wolf (Canis lupus) in southern Norway"&rft.inst=University of Oslo&rft.date=2006&rft.degree=Masteroppgave URN:NBN:no-14010 50488 070029385 Fulltext https://www.duo.uio.no/bitstream/handle/10852/11728/1/Masteroppgavex-xferdig.pdf |
_version_ |
1766260623282274304 |