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Abstract

Variation in kit fox (Vulpes macrotis) population parameters can be influenced by vegetative cover and the distribution and abundance of other predator and prey species. Dramatic changes to Great Basin Desert habitats, which can potentially impact mammalian species, have occurred in some areas in Utah. We examined kit fox demographics and prey populations from 1999 to 2001 on Dugway Proving Ground (DPG), a U.S. Army facility in Utah, and compared some parameters to historical levels (1956–1958, 1966–1969). Adult survival rates were fairly consistent between 1999 and 2000 and between 1999 and 2001; however, survival was greater in 2001 than in 2000. Reproductive rates ranged from 1.0 to 3.8 pups per female in 1999–2000 and were similar to historical numbers (1.0–4.2 pups per female). We found a decrease in pre-whelping kit fox density from the 1960s (0.12 foxes · km−2) to 1999–2001 (0.04 foxes · km−2); however, densities were similar between the current study and the 1950s (0.08 foxes · km−2). Using 9 years of data, we found density dependence between reproductive rates of the current year and annual fox density from the previous year. Using 7 years of data, we found a slight correlation between kit fox annual density and a 1-year lag in leporid abundance, even though leporid abundance was lower during the present study than it was historically. Compared to historical levels, current small mammal abundance and species composition has changed in several habitats. Kit fox breeding density and annual density were inversely correlated with coyote (Canis latrans) density. Changes to the landscape at DPG, especially due to invasion of cheatgrass (Bromus tectorum) and addition of artificial water sources, have caused a change in available kit fox habitat and prey species, and have increased the abundance of coyotes, the kit fox's major competitor.

Erratum

Several of the cited authors’ names were erroneously changed during the editing process. Throughout the article, B.L. Cypher appeared as B.L. Cipher; K. Ralls appeared as K. Walls; M.R.M. Otten appeared as M.R.M. Often; and R.A. Garrott appeared as R.A. Garroted. The following are the correct full citations:
CYPHER, B.L. 1993. Food item use by three sympatric canids in southern Illinois. Transactions of the Illinois State Academy of Science 86:139–144.
CYPHER, B.L., AND J.H. SCRIVENER. 1992. Coyote control to protect endangered San Joaquin kit foxes at the Naval Petroleum Reserves, California. Pages 42–47 in J.E. Borrecco and R.E. Marsh, editors, Proceedings of the 15th Vertebrate Pest Conference. University of California, Davis.
CYPHER, B.L., AND K.A. SPENCER. 1998. Competitive interactions between coyotes and San Joaquin kit foxes. Journal of Mammalogy 79:204–214.
CYPHER, B.L., G.D. WARRICK, M.R.M. OTTEN, T.P. O’FARRELL, W.H. BERRY, C.E. HARRIS, T.T. KATO, ET AL. 2000. Population dynamics of San Joaquin kit foxes at the Naval Petroleum Reserves in California. Wildlife Monographs 145:1–43.
DENNIS, B., AND M.R.M. OTTEN. 2000. Joint effects of density dependence and rainfall on abundance of San Joaquin kit fox. Journal of Wildlife Management 64:388–400.
RALLS, K., AND P. J. W HITE. 1995. Predation on San Joaquin kit foxes by larger canids. Journal of Mammalogy 76:723–729.
WARRICK, G.D., AND B.L. CYPHER. 1998. Factors affecting the spatial distribution of San Joaquin kit foxes. Journal of Wildlife Management 62:707–717.
WHITE, G.C., AND R.A. GARROTT. 1990. Analysis of radiotracking data. Academic Press, Inc., New York.
WHITE, P.J., AND R.A. GARROTT. 1997. Factors regulating kit fox populations. Canadian Journal of Zoology 75:1982–1988.
______. 1999. Population dynamics of kit foxes. Canadian Journal of Zoology 77:486–493.
WHITE, P.J., C.A. VANDERBILT WHITE, AND K. RALLS. 1996. Functional and numerical responses of kit foxes to a short-term decline in mammalian prey. Journal of Mammalogy 77:370–376.
WHITE, P.J., AND K. RALLS. 1993. Reproduction and spacing patterns of kit foxes relative to changing prey availability. Journal of Wildlife Management 57:861867.
WHITE, P.J., K. RALLS, AND R.A. GARROTT. 1994. Coyotekit fox interaction as revealed by telemetry. Canadian Journal of Zoology 72:1831–1836.
WHITE, P.J., K. RALLS, AND C.A. VANDERBILT WHITE. 1995. Overlap in habitat and food use between coyotes and San Joaquin kit foxes. Southwestern Naturalist 40:342–349.
We apologize for any misunderstandings that these errors might have caused.
Errata notice here: wnan/vol67/iss4/19

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