Morro Bay Kangaroo Rat - Nicholas Dekker

Morro Bay Kangaroo Rat

(Dipodomys heermanni morroensis)

Description and Ecology

The Morro Bay kangaroo rat, scientific name Dipodomys heermanni morroensis, is a small, nocturnal, burrowing rodent that is native to the central coast of California. Kangaroo rats are characterized by external cheek pouches, small front legs, large hind legs, long tails and large heads. It is one of 19 species of kangaroo rat, though it is smaller, darker, and has different markings than its subspecies relatives. The species is territorial and can generally be found on stabilized sand dunes near Morro Bay and the Pacific Ocean. Its optimal habitat includes coastal dune scrub with open spaces that are used for movement and collecting food.

Geographic and Population Changes

In 1957, the occupied habitat of the Morro Bay kangaroo rat was approximately 2.5 square miles and the population size was estimated to be more than 8,000 individuals. The habitat of the Morro Bay kangaroo rat is currently restricted to roughly 200 acres near the community of Los Osos in San Luis Obispo County. The species population has decreased as the species habitat range has decreased and the Morro Bay kangaroo rat has not been observed in the wild since 1986, when the total population was estimated to be only 50 individuals. The last individual held in captivity died in 1993. Potential signs of some isolated colonies have been observed, and there may also be populations on several surrounding private properties.

Listing Date and Description

10/13/1970

The Morro Bay kangaroo rat and other species are included on the United States List of Endangered Native Fish and Wildlife.

08/30/1976

A proposal is issued to determine the habitat of the Morro Bay kangaroo rat as critical habitat.

08/11/1977

The U.S. Fish and Wildlife Service determines the habitat of the Morro Bay kangaroo rat as critical habitat.

09/22/1977

The map of the critical habitat for the Morro Bay kangaroo rat and other endangered species is corrected and the critical habitats of additional species are outlined.

01/25/2000

The U.S. Fish and Wildlife Service makes available the Morro Bay Kangaroo Rat Draft Revised Recovery Plan for public review and comment.

https://ecos.fws.gov/docs/recovery_plan/000125.pdf

05/21/2010

The U.S. Fish and Wildlife Service initiates a 5-year review for the Morro Bay kangaroo rat and other species in order to determine whether those species are properly classified under the Endangered Species Act of 1973.

05/26/2011

The 5-Year Review of the Morro Bay Kangaroo Rat is published.

https://ecos.fws.gov/docs/five_year_review/doc3641.pdf

04/27/2012

The status of the Morro Bay kangaroo rat and other species is recommended to remain listed as endangered.

Cause of Listing and Main Threats to Continued Existence

As mentioned previously, the total population of the Morro Bay kangaroo rat was estimated to be only 50 individuals in 1986 and was spread over roughly 31 acres. The species is currently considered possibly extinct by the US Fish and Wildlife Service and the California Department of Fish and Game. The main threats to the existence of the species, if there is still a population left, is the destruction and fragmentation of habitat by human urban development and changes in the vegetation of habitat due to the absence of fire. Other threats include predation by dogs and cats, destruction of burrows by vehicles and pedestrians, and competition with other burrowing animals. 

Description of Recovery Plan

One of the first actions that has been taken as part of the recovery plan of the Morro Bay kangaroo rat is to continue the search for possible populations on both State and private lands, and if found, remove them from the wild. However, different methods will be used than those used previously, including grid trapping, saturation trapping, bait stations with cameras, and sniffer doges. Another feature of the plan for recovery is the restoration of habitat. This restoration would include brush and ice plant removal, the thinning of brush on experimental sites in the area, and the prescribed burning of brush around sites where potential signs have been observed. Breeding programs for the species have been met with mixed success, and breeding of the Lompoc kangaroo rat has been studied in order to gain information that may be applied to the Morro Bay kangaroo rat.

What Can You Do?

The best thing a person can do for a threatened or endangered species is to become educated on the species and its condition. By simply knowing the circumstances of the species and why it has become threatened or endangered is a step towards helping the species, even if it seems to be only a small step. Getting to know the situation surrounding the species is enough for the species cause to gain sympathy and perhaps support in a future petition or fundraiser. In the case of the Morro Bay kangaroo rat, for example, knowing the signs of the kangaroo rat’s presence can help conservationist find individuals. Understanding the threats to the kangaroo rat’s habitat can help keep the habitat intact and help to provide resistance to further urban development in important areas.

Resources

Environmental Conservation Online System (ECOS) Species Profile:

https://ecos.fws.gov/ecp0/profile/speciesProfile.action?spcode=A03X

Draft Revised Recovery Plan:

https://ecos.fws.gov/docs/recovery_plan/000125.pdf

U.S. Fish and Wildlife Service 5-Year Review:

https://ecos.fws.gov/docs/five_year_review/doc3641.pdf

Morro Bay Kangaroo Rat in Journal of Fish and Wildlife Management:

http://fwspubs.org/doi/pdf/10.3996/102014-JFWM-078