Stephens' Kangaroo Rat

Stephens’ Kangaroo Rat

By: Nick Major

Drafted For: BIO 227-01; Fall 2017; L. Needles

Description and Ecology

The Stephens’ Kangaroo Rat, or Dipodomys stephensi, is one of 19 kangaoo rats belonging to the Heteromyidae family, which is a family of rats which is related more to squirrels than other rats or mice. The Stephens’ Kangaroo Rat has large hind legs, small front legs, a long tail, and large check pouches to store food. The length of an adult is around 9 to 12 inches, including the tail. The fur of the rat is a cinnamon-colored, soft fur. The Stephens’ Kangaroo Rat was pronounced endangered on September 30, 1988, but has a recovery priority of 2C, meaning that it is endangered, but it is has a high potential for recovery. The ‘C’ at the end of the priority indicates that the species’ recovery may interfere with building or economic development.

Stephens’ Kangaroo Rat is endemic to Southern California areas, primarily San Bernardino, San Juaquin, and Riverside counties. Their habitat of the rat is grassland with little vegetation, which has been renovated into farms recently in Southern California and has forced this Kangaroo Rat into endangerment.

The rat does not have any use to humans, especially sine it’s small size, but it occupies land which humans want to develop into farms or urban cities, which threatens almost all areas the Kangaroo Rat occupies.

Geographic and Population Changes

The Stephens’ Kangaroo Rat’s range is primarily the western side Riverside County, extending into San Diego County. Their habitat consists of sparsely vegetated flatlands, which were plentiful in the area prior to endangerment. The rats are said to stay in the area due to the hills and mountains surrounding them, forcing them into one area. In 2008, it was determined that the species population was still declining and is severely fragmented. Ecologists found over 65 Stephens’ Kangaroo Rat sites occupied by the species which were under 40 hectares. The total adult population size is above 10,000, but severe fragmentation threatens this size, as number continue to decrease yearly, which has led to the endangered classification of the Kangaroo rat. The map to the right shows the small area the Stephens’ Kangaroo Rat occupies, which makes it an easy target for extinction, being that most sites of the species are in a small geographic range.

Listing Date and Type

The Stephen’s Kangaroo Rat was originally listed as threatened in 1971, and was later named endangered on September 30, 1988. The Kangaroo Rat has a listing type of 2C, meaning that it is not a very high priority because it has a high potential to be able to come back out of endangerment. The ‘C’ in the classification indicates that the recovery of the Stephens’ Kangaroo Rat will interfere with building or economic plans for humans in the future. With a high-fitness environment, the population is expected to rise again at a steady pace, hence the low priority placed on this species.

Cause of Listing and Main Threats of Extinction

The main cause of the decline in Stephens’ Kangaroo Rats is that the land occupied by these animals is highly sought by both private owners and city agencies, specifically for farmland or urban development. Most of the species live on private land and have actually been poisoned and killed in order to continue development without and consequences from the rats. Another threat to habitats of the species are non-native grasses, which grow alongside the Kangaroo Rats in their native environment and cause them to leave the area and move to a new location or site.

Description of Recovery Plan

Many agencies have come together to protect this species and similar species in the area, on a federal, state, and local level. From the federal jurisdiction, US Navy, Marines, and Air Force bases are working to protect land that this species lives on and have drafted their own management plans for the areas they are located in. The FWS has rallied support to help survey population as well as get a more specific range on the species, which has raised enough money to be able to get a better estimate on population size as well as a very precise range of the species. Multiple organizations, including the Bureau of Land Management have sent out parcels attempting to rally support for the conservation of these animals on a civilian level. The Lake Mathews Ecological Reserve and the San Jacinto Wildlife Area have been established and offer a protected environment for the species, which has allowed them to raise population slowly. The FWS is also trying to get a large reserve for the rats, which have a recommended habitat size of 1320 hectares.

Local agencies have a 4 step plan for conservation. 1) They will establish a core reservation system in the San Jacinto County area. 2) Work with the local land management bureau to ensure the land is maintained in a way that will keep the species population expanding. 3) Limit migrating species into the Kangaroo Rat’s habitat that compete with them or pray on them. 4) Expand the currently habitat conservation area of Stephens’ Kangaroo Rat by 1030 hectares. Most of the funding will be from the Riverside County Wildlife foundation, which will provide $11.6 million between conservation costs and habitat acquisition. The conservation effort ensures that the reserves are spread among the Kangaroo Rat’s natural range in order to keep them in their local communities.

The overall protection plan for these Kangaroo Rats is to conserve the land they live on and make sure that development cannot interfere with the regrowth of the Stephens’ Kangaroo Rat in the future. The recovery plan was implemented in the later 90s and is still ongoing in order to make sure the species grows, which it has not yet done.

What Can You Do?

Since most of the agencies running the conservation are government agencies, they don’t typically take donations. However, the Fish and Wildlife Service does accept donations, which can be made out to a certain cause (e.g. Stephens’ Kangaroo Rat conservation). By doing that, you ensure the donation goes directly to the cause you requested. You can also show support for the plan by writing to the Riverside Habitat Conservation Agency.

What Can You Do?

Riverside County Habitat Conservation Agency: http://www.skrplan.org/contact_us.html

FWS Stephens’ Kangaroo Rat Page: https://ecos.fws.gov/ecp0/profile/speciesProfile?spcode=A08Q

IUCN Page: http://www.iucnredlist.org/details/summary/6682/0

Dipodomys stephensi . (n.d.). Retrieved November 10, 2017, from http://www.iucnredlist.org/details/summary/6682/0

Stephens’ Kangaroo Rat Recovery Plan. (n.d.). Retrieved November 10, 2017, from https://ecos.fws.gov/docs/recovery_plan/970623.pdf

Service, U. F. (n.d.). Retrieved November 10, 2017, from https://ecos.fws.gov/ecp0/reports/implementation-activity-status-ore-report?documentId=400324&entityId=39

Chappell, M. (n.d.). Retrieved November 10, 2017, from http://faculty.ucr.edu/~chappell/INW/mammals/SKR.shtml