Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations
Lemmings are key herbivores in the Arctic and an integral part of the food web. Rising temperatures are decreasing snow quality and making the environment more hospitable for southern invaders. Consequently, southern species have expanded onto the tundra, including the meadow vole (Microtus pennsylv...
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ftunivmanitoba:oai:mspace.lib.umanitoba.ca:1993/36714 2023-06-18T03:38:53+02:00 Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations Dobroski, Morgan Roth, Jim Gillis, Darren Markham, John 2022-08-19T23:21:47Z application/pdf http://hdl.handle.net/1993/36714 eng eng http://hdl.handle.net/1993/36714 open access Habitat use Small mammals Northward expansion Migratory connectivity Habitat degradation Species interactions Dietary overlap master thesis 2022 ftunivmanitoba 2023-06-04T17:42:44Z Lemmings are key herbivores in the Arctic and an integral part of the food web. Rising temperatures are decreasing snow quality and making the environment more hospitable for southern invaders. Consequently, southern species have expanded onto the tundra, including the meadow vole (Microtus pennsylvanicus). Voles and lemmings play a similar functional role in the Arctic ecosystem and thus may compete for resources. In addition to expanding boreal species, lemmings may also compete for resources with migratory species. Lesser snow geese (Chen caerulescens caerulescens) breed in the Arctic and their population has increased exponentially due to land-use changes in their winter range. Snow goose grazing reduces graminoid abundance, leaving large patches of unvegetated land. Therefore, geese may indirectly impact lemming populations through habitat degradation. The objectives of this thesis were to (1) determine lemming and vole dietary overlap using stable isotope analysis and (2) analyze lemming winter habitat selection in an area impacted by snow geese. Our results suggest dietary overlap between vole and lemming populations is minimal. We also found that lemmings avoid goose-affected areas, suggesting geese may be indirectly impacting lemming habitat selection through habitat destruction. Thus, while lemming populations are declining in Arctic regions where they are sympatric with voles, habitat degradation by geese may be an additive factor contributing to lemming population declines. Ultimately, changes in lemming population abundance or distribution has the potential to disrupt the entire Arctic food web through changes in prey availability and predation risk. Northern Scientific Training Program; Oakes-Riewe Aboriginal-environmental Studies Research Award; Northern Research Fund - Churchill Northern Studies Centre October 2022 Master Thesis Arctic Tundra MSpace at the University of Manitoba Arctic |
institution |
Open Polar |
collection |
MSpace at the University of Manitoba |
op_collection_id |
ftunivmanitoba |
language |
English |
topic |
Habitat use Small mammals Northward expansion Migratory connectivity Habitat degradation Species interactions Dietary overlap |
spellingShingle |
Habitat use Small mammals Northward expansion Migratory connectivity Habitat degradation Species interactions Dietary overlap Dobroski, Morgan Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations |
topic_facet |
Habitat use Small mammals Northward expansion Migratory connectivity Habitat degradation Species interactions Dietary overlap |
description |
Lemmings are key herbivores in the Arctic and an integral part of the food web. Rising temperatures are decreasing snow quality and making the environment more hospitable for southern invaders. Consequently, southern species have expanded onto the tundra, including the meadow vole (Microtus pennsylvanicus). Voles and lemmings play a similar functional role in the Arctic ecosystem and thus may compete for resources. In addition to expanding boreal species, lemmings may also compete for resources with migratory species. Lesser snow geese (Chen caerulescens caerulescens) breed in the Arctic and their population has increased exponentially due to land-use changes in their winter range. Snow goose grazing reduces graminoid abundance, leaving large patches of unvegetated land. Therefore, geese may indirectly impact lemming populations through habitat degradation. The objectives of this thesis were to (1) determine lemming and vole dietary overlap using stable isotope analysis and (2) analyze lemming winter habitat selection in an area impacted by snow geese. Our results suggest dietary overlap between vole and lemming populations is minimal. We also found that lemmings avoid goose-affected areas, suggesting geese may be indirectly impacting lemming habitat selection through habitat destruction. Thus, while lemming populations are declining in Arctic regions where they are sympatric with voles, habitat degradation by geese may be an additive factor contributing to lemming population declines. Ultimately, changes in lemming population abundance or distribution has the potential to disrupt the entire Arctic food web through changes in prey availability and predation risk. Northern Scientific Training Program; Oakes-Riewe Aboriginal-environmental Studies Research Award; Northern Research Fund - Churchill Northern Studies Centre October 2022 |
author2 |
Roth, Jim Gillis, Darren Markham, John |
format |
Master Thesis |
author |
Dobroski, Morgan |
author_facet |
Dobroski, Morgan |
author_sort |
Dobroski, Morgan |
title |
Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations |
title_short |
Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations |
title_full |
Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations |
title_fullStr |
Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations |
title_full_unstemmed |
Interactions on the Arctic tundra between endemics, migrants, and northward expanding rodent populations |
title_sort |
interactions on the arctic tundra between endemics, migrants, and northward expanding rodent populations |
publishDate |
2022 |
url |
http://hdl.handle.net/1993/36714 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Tundra |
genre_facet |
Arctic Tundra |
op_relation |
http://hdl.handle.net/1993/36714 |
op_rights |
open access |
_version_ |
1769003732163362816 |