Identifying priority conservation areas using systematic reserve selection and GIS at a fine spatial scale : a test case using threatened vertebrate species in the Okanagan, British Columbia

• Main Author: Warman, Leanna Dawn
• Language: English
• Published: 2009
• Online Access: http://hdl.handle.net/2429/12317

Biologists and wildlife managers recognise the need for systematic reserve selection techniques to conserve habitat for species. Geographic information systems (GIS) provide a tool that helps identify conservation areas using geographically referenced data. Mapping continuous geographical phenomena with discreet boundaries affects the spatial organisation of data. However, most published studies of systematic reserve selection techniques have been completed at only one level of data organisation and usually for large regions at coarse scales. In this thesis, I examined the effects of data organisation on reserve selection in the South Okanagan, a small region in British Columbia. I used the software program "C-Plan" with ArcView GIS to identify the minimum amount of area required to achieve explicit conservation targets that maintain species within the region. I evaluated the reserve selection technique using terrestrial ecosystem mapping (TEM) and species habitat models that predict the suitability of T EM polygons for each of twenty-nine threatened vertebrate species. C-Plan selected 37.2% of the region to represent habitat that maintains current population sizes of these threatened vertebrate species. Although habitat area targets were achieved, these priority sites were small and scattered throughout the region and were therefore not practical for implementation or viable for many species. I examined the effects of data organisation on priority site selection by altering three algorithm parameters: (1) size and shape of the unit used to map data and select sites, (2) type of species included in selections, and (3) quantity of the conservation target for each species. The spatial overlap of priority sets of sites that were identified for different values of each parameter was low. Therefore, the spatial distribution of priority conservation sites depends on values for these parameters. Data organisation also influenced the evaluation of existing protected areas in the region for maintaining the threatened vertebrate species. Both selection unit size and assignment of protection status to selection units, based on area of overlap with actual protected areas, resulted in different evaluations of reserve performance. I demonstrate that systematic reserve selection cannot be performed with data at only one spatial organisation unless the consequences are recognised.