Browsing by Subject "occupancy"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Occupancy Survey Data and analysis code for shorebird and waterfowl habitat use in NW North Dakota, 2014-2015
    (2018-11-19) Specht, Hannah; spech030@umn.edu; Specht, Hannah; University of Minnesota Fisheries, Wildlife and Conservation Biology
    Data and R code examine quarter-section site occupancy rates of upland nesting waterbirds relative to oil well density and traffic activity to accompany H. Specht PhD Thesis 2018, University of Minnesota.
  • Thumbnail Image
    Item
    Post-Fire Associations Of Butterfly Behavior, Occupancy, And Abundance With Environmental Variables And Nectar Sources In The Sierra Nevada, California
    (2015-12) Pavlik, David
    Fire can alter the quality of habitat for butterflies. Fire also affects environmental attributes associated with the distribution, abundance, and reproduction of butterflies. The effects of fire on butterfly occupancy, and on environmental attributes that are associated with butterfly occupancy, are largely unknown. In 2014 and 2015, we conducted butterfly and vegetation surveys within the Rim Fire boundary in California. We analyzed sugar and sucrose masses, and proportion of sucrose, in 20 nectar sources. We found no evidence that intensity of use was associated with sugar mass, mass of sucrose, or the relative proportion of sucrose. We found that environmental attributes associated with occupancy of some species were also associated with the abundances of those species. Burn severity affected environmental attributes that were associated with butterfly occupancy and abundance. Understanding how fire affects environmental attributes associated with occupancy and abundance can inform use of prescribed fire or management following wildfire.
  • Thumbnail Image
    Item
    Spatio-temporal Ecology of Forest Birds
    (2015-05) Grinde, Alexis
    Maintaining avian diversity in forest ecosystems have been shown to afford many benefits for forest health and productivity. However, alterations to the historical disturbance regimes within hemiboreal forests have impacted bird communities, and the ability of landscapes to meet the ecological needs of breeding forest birds has become a growing concern. As changes in forest landscapes continue, landscape effects may become increasingly important drivers of population dynamics for forest bird species. This dissertation includes a combination of experimental, theoretical, and applied research to assess the influence of habitat, landscape, community composition, and life history traits on population dynamics of forest birds. This research aids in identifying mechanisms associated with species population dynamics which is critical for understanding long term population trends and factors that contribute to species persistence and maintenance of biodiversity.