Show simple item record

dc.contributor.advisorChairperson, Graduate Committee: Robert K. D. Petersonen
dc.contributor.authorDittemore, Clare Mikaelaen
dc.contributor.otherThis is a manuscript style paper that includes co-authored chapters.en
dc.coverage.spatialGreat Plainsen
dc.date.accessioned2022-10-07T18:39:58Z
dc.date.available2022-10-07T18:39:58Z
dc.date.issued2022en
dc.identifier.urihttps://scholarworks.montana.edu/xmlui/handle/1/16903en
dc.description.abstractThe army cutworm moth, Euxoa auxiliaris, is a migratory noctuid that migrates from and returns to the Great Plains. At their Rocky Mountain summering range, it is an important food for the Greater Yellowstone Ecosystem (GYE) grizzly bears, Ursus arctos horribilis. However, a limited understanding of moth migratory patterns, abundance at summering ranges, and the associated vulnerability and variability of these populations, is a shortfall in agency grizzly bear conservation strategies. Therefore, the objectives of our study were to assess the natal origin of moths collected from two mountain ranges and within the Great Plains, characterize larval feeding habits of migrants collected from the Absaroka Range, and assess a monitoring protocol to determine moth abundance at a GYE aggregation site. Using stable isotopes, we estimated the natal origin of migrants collected from the Absaroka and Lewis Ranges, examined migratory patterns within the Great Plains, and assessed the larval feeding habits of migrants collected in the Absaroka Range during 2017-2021. To estimate abundance, we sampled the airspace with a radar stationed within 1 km of an aggregation site in the GYE during 2020 and 2021. There was strong evidence that moths collected in the Great Plains and both mountain ranges were migrating north-south, in addition to previously established east-west movement. Although their origins were varied, moths of the Absaroka Range had the highest probability of origin in Alberta and British Columbia, and moderate probability in Montana, Idaho, and Wyoming across all collection years. Lewis Range moths had the highest probability of origin almost exclusively within the lower third of Canada. As larvae, the moths collected from the Absaroka Range fed almost exclusively on C3 plants. We estimate that 5 million moths passed through our radar's sampling plane (160-750 m above ground level and 2600 m across) over the course of 20 hours (5 nights of movement). Overall, our findings suggest that army cutworm moths at aggregation sites are 'supplied' by various source locations, and thus insulated against regional declines within their natal origins. Radar should be used at moth aggregation sites to continue monitoring army cutworm moths.en
dc.language.isoenen
dc.publisherMontana State University - Bozeman, College of Agricultureen
dc.subject.lcshNoctuidaeen
dc.subject.lcshInsect populationsen
dc.subject.lcshInsects--Migrationen
dc.subject.lcshBiogeographyen
dc.titleNatal origin, migratory patterns, and abundance of the army cutworm moth, Euxoa auxiliarisen
dc.typeThesisen
dc.rights.holderCopyright 2022 by Clare Mikaela Dittemoreen
thesis.degree.committeemembersMembers, Graduate Committee: Dan Tyers; David K. Weaveren
thesis.degree.departmentLand Resources & Environmental Sciences.en
thesis.degree.genreThesisen
thesis.degree.nameMSen
thesis.format.extentfirstpage1en
thesis.format.extentlastpage146en
mus.data.thumbpage102en


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record


MSU uses DSpace software, copyright © 2002-2017  Duraspace. For library collections that are not accessible, we are committed to providing reasonable accommodations and timely access to users with disabilities. For assistance, please submit an accessibility request for library material.