UVM Theses and Dissertations
Format:
Print
Author:
Bettigole, Charles
Title:
Dept./Program:
Natural Resources
Year:
2012
Degree:
MS
Abstract:
The conversion of natural lands to developed uses may pose the single greatest human threat to global terrestrial biodiversity. Continued human growth and development over the next century will further exacerbate these effects of habitat loss and fragmentation. Natural resource managers, tasked with managing wildlife as a public trust, must have techniques for predicting how much and where wildlife habitat is likely to be converted in the future. Here, we use methodology which measures the "social carrying capacity of a landscape" (SKd) -defined as the potential of an area for future human population growth and development, based on residents' responses to visual preference surveys, which depict landscapes that vary in development and natural lands.
We performed a visual preference survey (n = 1505 responses) across the state of Vermont, USA, and used multi-model selection and AlC to fit a cubic function to the response data, allowing us to predict SKd at a town scale based on demographic characteristics. These norms reflect the capacity of the landscape for change (SKd), or the potential future conditions if development were to proceed unchecked. Next, we adapted existing occupancy models for American black bear (Ursus americanus), fisher (Martes pennanti), and bobcat (Lynx rufus) to predict species occurrence under present and SKd conditions at a 30 m² resolution, and then compared species occurrence at the town scale between present and SKd.
With nearly 90% of Vermont towns exhibiting capacity for future development under SKd, we predict significant change in occurrence for all three focal species, with black bear seeing the greatest change (a decrease in occurrence of 15,9%). Bobcat exhibited slight decreases in statewide occupancy under SKd (3.1%), while fisher displayed statewide increases in occurrence under SKd (9,0%). The results of this analysis will allow natural resource managers and decision makers a spatially explicit understanding of which communities may be at risk of future development, and where wildlife habitat may be threatened.
We performed a visual preference survey (n = 1505 responses) across the state of Vermont, USA, and used multi-model selection and AlC to fit a cubic function to the response data, allowing us to predict SKd at a town scale based on demographic characteristics. These norms reflect the capacity of the landscape for change (SKd), or the potential future conditions if development were to proceed unchecked. Next, we adapted existing occupancy models for American black bear (Ursus americanus), fisher (Martes pennanti), and bobcat (Lynx rufus) to predict species occurrence under present and SKd conditions at a 30 m² resolution, and then compared species occurrence at the town scale between present and SKd.
With nearly 90% of Vermont towns exhibiting capacity for future development under SKd, we predict significant change in occurrence for all three focal species, with black bear seeing the greatest change (a decrease in occurrence of 15,9%). Bobcat exhibited slight decreases in statewide occupancy under SKd (3.1%), while fisher displayed statewide increases in occurrence under SKd (9,0%). The results of this analysis will allow natural resource managers and decision makers a spatially explicit understanding of which communities may be at risk of future development, and where wildlife habitat may be threatened.