Impact of prey availability and diet on stress in arctic foxes
| dc.contributor.author | McDonald, Ryan | |
| dc.contributor.examiningcommittee | Anderson, Gary (Biological Sciences) Waterman, Jane (Biological Sciences) Crow, Gary (Animal Science) | en_US |
| dc.contributor.supervisor | Roth, James (Biological Sciences) | en_US |
| dc.date.accessioned | 2014-01-15T20:31:12Z | |
| dc.date.available | 2014-01-15T20:31:12Z | |
| dc.date.issued | 2014-01-15 | |
| dc.degree.discipline | Biological Sciences | en_US |
| dc.degree.level | Master of Science (M.Sc.) | en_US |
| dc.description.abstract | Arctic food webs are characterized by multi-year predator-prey cycles. Arctic foxes (Vulpes lagopus) feed primarily on rodents, but also on avian and marine prey when rodents are scarce. I examined temporal variation in the arctic fox diet related to food availability and stress hormones (i.e. cortisol). Lemmings (Dicrostonyx richardsoni), goslings, and goose eggs were important components of the fall and winter diet. Goslings were important in fall, even when rodents were abundant. Lemmings were most important in winter, even when lemming densities were low. Consuming stored eggs did not reduce cortisol concentrations, suggesting that arctic foxes do not prefer stored eggs to lemmings. I also found that prey hormones increased fecal hormone concentrations of captive arctic foxes, introducing an additional caution for hormone studies involving predators. Nonetheless, relationships between stress hormone concentrations and changes in food availability can provide insight regarding the importance of food sources to consumer populations. | en_US |
| dc.description.note | February 2014 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/23248 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | stable isotope analysis | en_US |
| dc.subject | cortisol | en_US |
| dc.subject | population cycles | en_US |
| dc.subject | ecology | en_US |
| dc.subject | trophic interactions | en_US |
| dc.subject | food web | en_US |
| dc.subject | hormones | en_US |
| dc.title | Impact of prey availability and diet on stress in arctic foxes | en_US |
| dc.type | master thesis | en_US |
| local.subject.manitoba | yes | en_US |