Photo Credit: Denise Clark, UGSS
Photo Credit: Denise Clark, UGSS
| Historically present | |
| Currently present | |
| Currently not detected |
Goal: Protect, enhance, and restore Stephens’ kangaroo rat occupied habitat and historically occupied habitat and the landscape connections between them to create resilient, self-sustaining populations that provide for persistence over the long-term (>100 years).
Management units: 5, 9
Inspect extant Stephens’ kangaroo rat occurrences on Conserved Lands (see occurrence table) using the regional IMG monitoring protocol to record abundance and collect habitat and threats covariate data to determine management needs.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Based upon occurrence status and threats, determine management needs including whether routine management or more intensive management is warranted. | available for implementation | |
| IMP-2 | Submit project metadata, monitoring datasets and management recommendations to the MSP Web Portal. | available for implementation |
| Criteria | Deadline year |
|---|---|
| Surveys Completed in 2018 with Management Recommendations | 2018 |
| Threat Name | Threat Code |
|---|---|
| Human uses of the Preserves | HUMUSE |
Management units: 5, 9
Conduct routine management actions as identified through the IMG monitoring at Stephens' kangaroo rat occurrences on Conserved Lands (see occurrence table). Depending on the type and level of threat, management should be conducted as needed, not necessarily every year, and using BMPs with precautions to do no harm.
| Action | Statement | Action status | Projects |
|---|---|---|---|
| IMP-1 | Perform as needed routine management activities, such as protecting occurrences from disturbance through fencing and enforcement and controlling invasive non-native plant species =20% absolute cover. | ||
| IMP-2 | Submit project metadata and management data to the MSP Web Portal. |
| Criteria | Deadline year |
|---|---|
| Routine Management Completed as Needed Based Upon Monitoring Recommendations | 2021 |
| Threat Name | Threat Code |
|---|---|
| Human uses of the Preserves | HUMUSE |
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Regional Grazing Monitoring Plan
This project evaluates using grazing as a management tool for degraded grasslands and coastal sage scrub habitat. Pilot projects will be conducted to look at the efficacy of grazing as management tool and necessary monitoring methods. The project was designed to answer four primary questions (and their associated objectives): 1) How effective is grazing at reducing fire risk? 2) Can grazing effectively enhance disturbed native grassland and forb habitats 3) Can grazing enhance disturbed native coastal sage scrub habitat? 4) Can grazing reduce nonnative grass and forb cover in disturbed coastal sage scrub to increase native shrub cover and bare ground and improve habitat for MSP species such as Quino checkerspot butterfly (Euphydryas editha quino), California gnatcatcher (Polioptila californica), and black-tailed jackrabbit (Lepus californicus)? Initial study sites were established at Rancho Jamul Ecological Reserve and Hollenbeck Canyon Wildlife Area. This is a SANDAG-funded project.
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Most of the range occurs in western Riverside County, with the northern end of the present range extending into southwestern San Bernardino County and the southern portion into northern San Diego County [1]. Currently exists only in fragmented populations separated by urban landscapes [2].
Population on Ramona Grasslands Preserve is only one on Conserved Lands in San Diego County. Other populations are found at MCB Camp Pendleton, Naval Weapons Station Fallbrook, Rancho Guejito, and Lake Henshaw/Warner Springs [2].
FE, CT
Native to open grasslands and sparse coastal sage scrub. Found from approximately 55-1250 m above sea level and typically occurs on relatively flat or gently sloping ground [3;4]. Typical habitat consists of native and nonnative annual herbs, filaree, native and nonnative grasses. Also found in sparse coastal sage scrub habitat where perennial species such as encelia, coastal sagebrush, and California buckwheat occur. Certain nonnative grasses can exclude this species from otherwise suitable habitat (e.g. Bromus diandrus) [3].
It is 1 of 19 species of kangaroo rats (genus Dipodomys) that compromise a distinct group of rodents belonging to the family Heteromyidae [3;5].
A nocturnal, solitary, and burrow-dwelling mammal [1;4]. Individuals spend little time above ground (approximately one hour per night) [1]. Breeding season may occur in late spring and early summer [6].
Average litter size is 2.5 [7]. Construct burrows to serve as sleeping quarters and nesting sites [6;8].
Primarily eat seeds, along with some green vegetation and occasional insects. Highly evolved to survive arid conditions, can persist indefinitely without drinking free water [4].
Reported home ranges of individuals vary from approximately 0.05 hectare to nearly 0.2 hectare [6;9 cited from 3]. As population density increases, the mean home range size decreases [9 cited from 3]. Male home ranges were significantly larger and had more activity centers than female home ranges. Observed seasonal variation in female home home range size, with smaller home ranges during lactation as females stay near the nest to feed and protect the young. Males ranged widely and their activity centers often overlapped those of neighboring females. Male home ranges were also much more irregularly shaped than females. Female ranges were generally oval or circular in shape, usually had one or two centers of activity, and home range overlap among females was minimal [10 cited from 3].
Threats include habitat loss resulting from widespread, rapid urbanization and agricultural development; fragmented and isolated populations throughout its range; reduction of habitat suitability from anthropogenic activities including disking for weed abatement, plowing, introduction of nonnative vegetation that kill individuals or destroy or degrade habitat, pasture improvement, or dry farming; application of rodenticides and perhaps other pesticides; predation by domestic pets; overgrazing by livestock; soil compaction by off-road vehicles, horses, and other livestock; and climate change [4;5].
[1] Burke, R.L., J. Tasse, C. Badgley, S.R. Jones, N.Fishbein, S. Phillips, and M.E. Soulé. 1991. Conservation of the Stephens' kangaroo rat (Dipodomys stephensi): Planning for persistence. Bulletin of the Southern California Academy of Sciences 90, no. 1: 10-40.
[2] Shier, D.M. and A. Navarro. Range-wide Genetics of the Stephens' Kangaroo rat (Dipodomys Stephensi).Final Report. 33 pp.
[3] U.S. Fish and Wildlife Service. 1997. Draft recovery plan for the Stephen’s kangaroo rat. Portland, OR.
[4] Spencer, W.D. 2005. Stephens’ Kangaroo Rat Survey. Conservation Biology: 2.
[5] U.S. Fish and Wildlife Service. 2011. Stephen's Kanagroo Rat (Dipodomys stephensi) 5-Year Review: Short For Summary. Carlsbad Fish and Wildlife Office, Carlsbad, California, USA.
[6] Bleich, V.C. 1977. Dipodomys stephensi. Mammalian Species 73: 1-3.
[7] Lackey, J.A. 1967. Growth and development of Dipodomys stephensi. Journal of Mammalogy 48, no. 4: 624-632.
[8] Jones, W.T. 1985. Body size and life-history variables in heteromyids. Journal of Mammalogy 66, no. 1: 128-132.
[9] Thomas, J.R. 1975. Distribution, population densities, and home range requirements of the Stephens kangaroo rat (Dipodomys stephensi).
[10] Kelly, P.A. and M.V. Price. 1992. Home range use of Stephens' kangaroo rats: implications for density estimation. Final report to the Riverside County Habitat Conservation Agency, Part B 15.