Skip to Main Content
Optimizing reserve expansion for disjunct populations of San Joaquin kit foxAuthor(s): Robert G. Haight; Brian Cypher; Patrick A. Kelly; Scott Phillips; Katherine Ralls; Hugh P. Possingham
Source: Biological Conservation 117:61-72
Publication Series: Scientific Journal (JRNL)
Station: North Central Research Station
PDF: Download Publication (1.37 MB)
DescriptionExpanding habitat protection is a common strategy for species conservation. We present a model to optimize the expansion of reserves for disjunct populations of an endangered species. The objective is to maximize the expected number of surviving populations subject to budget and habitat constraints. The model accounts for benefits of reserve expansion in terms of likelihood of persistence of each population and monetary cost. Solving the model with incrementally higher budgets helps prioritize sites for expansion and produces a cost curve showing funds required for incremental increases in the objective. We applied the model to the problem of allocating funds among eight reserves for the endangered San Joaquin kit fox (Vulpes macrotis mutica) in California, USA. The priorities for reserve expansion were related to land cost and amount of already-protected habitat at each site. Western Kern and Ciervo-Panoche sites received highest priority because land costs were low and moderate amounts of already-protected habitat resulted in large reductions in extinction risk for small increments of habitat protection. The sensitivity analysis focused on the impacts of kit fox reproductive success and home range in non-native grassland sites. If grassland habitat is lower quality than brushland habitat resulting in higher annual variation in reproductive success or larger home ranges, then protecting habitat at the best grassland site (Ciervo-Panoche) is not cost-efficient relative to shrubland sites (Western Kern, Antelope Plain, Carrizo Plain). Finally, results suggested that lowest priority should be given to three relatively high-cost grassland sites (Camp Roberts, Contra Costa, and Western Madera) because protecting habitat at those sites would be expensive and have little effect on the expected number of surviving kit fox populations.
- Check the Northern Research Station web site to request a printed copy of this publication.
- Our on-line publications are scanned and captured using Adobe Acrobat.
- During the capture process some typographical errors may occur.
- Please contact Sharon Hobrla, email@example.com if you notice any errors which make this publication unusable.
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationHaight, Robert G.; Cypher, Brian; Kelly, Patrick A.; Phillips, Scott; Ralls, Katherine; Possingham, Hugh P. 2004. Optimizing reserve expansion for disjunct populations of San Joaquin kit fox. Biological Conservation 117:61-72
KeywordsEndangered species, Habitat protection, Kit fox, Reserve design, San Joaquin Valley
- Optimizing habitat protection using demographic models of population viability.
- Vegetative characteristics of swift fox denning and foraging sites in southwestern South Dakota
- Detecting swift fox: Smoked-plate scent stations versus spotlighting
XML: View XML