Dipodomys merriami parvus was listed as endangered by the U. S. Fish and Wildlife service (USFWS) in September 1998 following its emergency listing of January 1998. A Biological Opinion issued by USFWS on a sand and gravel mining within Cajon Wash, an area of critical habitat, included translocation as a minimization measure. Preliminary to translocation, a salvage trapping effort was initiated in May 1998 to remove animals from a 32.5-ha site scheduled for mining operations. Fifteen D. m. parvus (11 males and 4 females) were captured and released on a re-vegetated reclamation site that contained a complement of native rodents including three resident D. m. parvus. All translocated animals were reproductively active. Translocation success was assessed in August 1998. Thirty-three percent of the original resident D. m. parvus and 40% of the translocated individuals were still present on the site. In contrast, among resident animals of other species, 57.1% of Dipodomys simulans and 15.4% of Peromyscus maniculatus remained on the site. Three juvenile D. m. parvus, apparently offspring from released animals, were captured in the release area. All adult D. m. parvus captured in August showed signs of reproductive activity, including evidence of a second litter in progress. Continued monitoring will verify the apparent short-term success of the translocation and suggest refinements for future efforts.
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