Document Type

Dissertation - Open Access

Award Date

2024

Degree Name

Doctor of Philosophy (PhD)

Department / School

Natural Resource Management

First Advisor

Robert C. Lonsinger

Second Advisor

Joshua D. Stafford

Abstract

The plains spotted skunk (Spilogale interrupta) is a data-deficient small carnivore native to the central plains of North America that has experienced significant population declines. My dissertation investigates the species’ distribution, habitat associations, and interspecific interactions in South Dakota, providing crucial information for conservation actions. In Chapter 1, I developed ensemble distribution models on a broad scale, incorporating species location data from 1985–2020, environmental factors, and six predictive modeling algorithms. I identified key predictors including mean temperature diurnal range and proportion of area as pasture, and estimated ~31,300 km2 of potential habitat, predominately in eastern South Dakota. In Chapter 2, I tracked radio-telemetered plains spotted skunks in spring and summer of 2021 and 2022. I analyzed resource selection at the point scale with 300 m2 buffers for landcover variables. My mixed-effects logistic regression analysis indicated that plains spotted skunks selected for areas near permanent small-scale farming structures (i.e., rock piles, fences, and farm buildings) and avoided crop cover, with varying responses to human development, wetland density, and hay bales across seasons. My results highlight the plains spotted skunk’s adaptability to different land uses, emphasizing the importance of low-intensity agricultural practices in determining habitat suitability. In Chapter 3, I examined interspecific interactions of plains spotted skunk within their ecological communities. Analyzing live-trap data from spring of 2021 and 2022, I investigated the influence of coyote management strategies on species occupancy probabilities, including the co-occurrence patterns of domestic cats, striped skunks, and thirteen-lined ground squirrels. My results indicated significant associations between areas with systematic coyote removal and occupancy probabilities for each mesocarnivore species. Plains spotted skunks and cats exhibited higher occupancy within areas with contracted annual predator control, while striped skunk occupancy was lower outside of these areas. Despite potential competition and predation effects of striped skunks and cats on spotted skunks, my co-occurrence analyses indicated that spotted skunks occurred independently of both species, while the conditional cooccurrence of thirteen-lined ground squirrels in relation to the presence or absence of plains spotted skunks indicated a potential predator-prey interaction. By integrating finescale habitat analysis and interspecific interactions with broad-scale distribution modeling, using a mix of historical (1985–2020) and contemporary (2021–2022) data, my research my research identified pasture, developed vegetation, and landscape diversity as important predictors for plains skunk habitat, informing targeted conservation efforts. Additionally, specific microhabitat features like rock piles, fence rows, and farm buildings were identified as essential and should be prioritized in management strategies that balance conservation goals with agricultural needs. My research highlighted the need for understanding seasonal and regional variation in the species’ habitat associations for adaptable conservation planning. Finally, my research on interspecific interactions, particularly with coyotes, indicates the importance of considering indirect management effects on conservation management for plains spotted skunk populations.

Library of Congress Subject Headings

Spotted skunks -- Ecology -- South Dakota.
Spotted skunks -- South Dakota -- Geographical distribution.
Spatial ecology.
Biogeography.
Biotic communities.

Publisher

South Dakota State University

Download

Share

COinS
 

Rights Statement

In Copyright