The Giant Kangaroo Rat - Amanda Stahler

The Giant Kangaroo Rat

“Humanity can no longer stand by in silence while our wildlife are being used, abused and exploited. It is time we all stand together, to be the voice of the voiceless before it's too late. Extinction means forever.” 

― Paul Oxton

Founder of Wild Heart Wildlife Foundation

Description and Ecology

The Giant Kangaroo Rat 
(Photo By John Roser. ARKIVE,http://www.arkive.org/giant-kangaroo-rat/dipodomys-ingens/ )

The Giant Kangaroo Rat, also known as Dipodomys Ingens, is a heteromyid rodent endemic to California. The Giant Kangaroo Rat is not only an endangered species, but is also a keystone species, playing a vital part in its ecosystem. Even though it is the largest of its species, this adorably small rodent is barely 150 grams. They use bipedal locomotion, which is two-footed hopping, jumping around on its large hind limbs with a short neck and flat large head. If that isn’t cute enough, they also have a small tuft of long hairs on the end of their tails and have large fur-lined cheek pouches. (Davison)

The Giant Kangaroo Rat’s diet is primarily seed based, but also contains green plants and insects. They have an intricate burrowing system, where they first gather individual seeds scattered over the ground surface, fill their cheek pouches with the harvest seeds, and then finally place the seeds in little pits. They then cover th epits with the seeds with a loose layer of dirt to let them dry. They have the ability to transport large quantities of food in their cheek pouches, especially lactating females. They harvest for food from sunset to near sunrise, but they are most active the first two hours after dark. Their highly developed harvesting behaviors and the relatively high longevity of adults with established burrow systems allows them to endure severe droughts. (U.S. Fish and Wildlife Service). Even though they are extremely cute and have very unique and effective harvesting skills they still face many threats.

Geographic Location and Population Changes

Extant Distribution of the Giant Kangaroo Rat
 (Endangered Species Recovery Program, U.S. Fish and Wildlife Service,http://esrp.csustan.edu/publications/pubhtml.php?doc=sjvrp&file=chapter02H00.html)

The Giant Kangaroo Rat’s habitat has greatly been reduced, especially compared to their historical distribution. Before the 1950’s their habitat was estimated to spread over 1.5 million acres across the Western San Joaquin Valley, Carrizo Plain, and Cuyama Valley. Currently their populations have been greatly fragmented into different geographical units due to barriers such as steep terrain, agricultural land, industries, and urban land use that offer unsuitable or no habitat options for the rat (U.S. Fish and Wildlife Service).

Their extant habitat is estimated to be 27,540 acres, about 2 percent of historical habitat. The units are now located in the southern San Joaquin Valley are the Kettleman Hills in Kings County's and Lokern, Elk Hills, and other uplands around McKittrick, Taft, and Maricopa in Western Kern County. Changes in their population density generally coincide with amount of rainfall and herbaceous plants (Davison). Since their habit has been reduced by nearly 98%, the Giant Kangaroo Rat has been put on the endangered species list.

Endangered Listing Date and Type

The Giant Kangaroo Rat was officially declared endangered by the Endangered Species Act in 1980, then by the California Endangered Species Act in 1987, and finally by the IUCN (International Union for the Conservation of Nature) Red List in 2008. Their recovery plan was established on September 30, 1998 for the California and Nevada region. They are listed as an E species, endangered, and are currently in the plan stage F, which means the final plan is approved by the Regional Director. (U.S. Fish and Wildlife Service)

Cause of Endangerment and Main Threats

The Giant Kangaroo Rat faces threats from Industrial Exploitation (https://www.konicaminolta.com/kids/endangered_animals/library/field/giant-kangaroo-rat.html)

The Giant Kangaroo Rat is threatened by agricultural and urban development, rodenticides, and oil drilling and exploration. The primary cause of their habitat loss is from the agricultural development in the San Joaquin Valley and the death of many Giant kangaroo Rats is due to rodenticides used to control ground squirrels (U.S. Fish and Wildlife Service. The sale of Naval Petroleum Reserve number in Elk Hills to private interests could represent a threat to one of largest regional populations of the Giant Kangaroo Rat, because that could result in the increase in the rates of exploitation (U.S. Fish and Wildlife Service). Urban and industrial Development, petroleum and mineral extraction, new energy and water conveyance facilities, construction, and transportation infrastructures are also destroying the habitats for the Giant Kangaroo Rats and increase the threats to the species by reducing and further fragmenting populations. (Davison).

San Joaquin Kit Fox preys on the Giant Kangaroo Rat
 (http://pixdaus.com/gotcha-fox-and-kangaroo-rat-nature-wildlife/items/view/78175/)

The Giant Kangaroo Rat is a critical part of the ecosystem for the areas they inhabit and their existence is crucial to the existence of other endangered species. The Giant Kangaroo Rat is the keystone species of the Carrizo Plain, serving as the foundation for the entire ecosystem. Their survival is critical to the existence of multiple species such as the San Joaquin kit fox, the blunt-nosed leopard lizard, and the San Joaquin antelope squirrel. They are the main diet for the San Joaquin kit fox and their burrows provide shelter for the squirrels and lizards. 

Wildflowers in bloom in the Carrizo Plains National Monument 
(https://calcoastnews.com/2017/08/carrizo-plain-national-monuments-fate-still-unknown/)

In the Carrizo plain Natural Area, which is threatened by the review by the Trump Administration by the Secretary of Interiors Ryan Zinke, is the home to the endangered California Jewelflower ,whose growth depends on the soil conditions made from the burrowing system of the rat (“Giant Kangaroo Rat.” Los Padres ForestWatch). Though there are many population-monitoring plots of land that were set in place since 1995, they are no longer receiving funding for proper monitoring and management. (U.S. Fish and Wildlife Service).

Recovery Plan

The Giant Kangaroo Rat needs your help! (http://drakehs.org/academics/seadisc/endangeredspecies/2008/Giant%20Kangaroo%20Rat/wEBPAGE2.htm)

Substantial progress has been made in terms of research and habitat protection, however a specific recovery plan for the Giant Kangaroo Rat is still needed for their survival. Certain organizations have taken steps to help with their protection such as the US Department of Energy Naval Petroleum Reserves in California, which is now publicly owned. This will help to ensure that Giant Kangaroo Rat’s habitat will be protected during and after extraction of petroleum deposits and won’t be harmfully exploited by large oil corporations. The state of California US government has acquired private property in the Carrizo Plain natural area, which will help to reduce threats to the species from cultivation and illegal use of rodenticide. (U.S. Fish and Wildlife Service).

Three major steps towards the recovery of the Giant Kangaroo Rat:

1.       The number one priority is habitat protection through proper land use and management. This starts by making land publicly owned and conserved in the Carrizo Plain national area, Naval petroleum reserves in California, Lokern Natural Area in Sierraville Panoche Natural Area. Land that is already in public and conservation ownership should also be maintained properly.
2.      Increasing research on habitat management and restoration, focusing on effects of livestock grazing on habitat quality and habitat restoration on retired farmland, especially abandoned dry land farms
3.      Continuing to protect land supporting key populations. Examples of some of these areas include the Lockern area, Naval Petroleum Reserves, Western Fresno and Eastern San Benito counties, the strip along the West of Interstate Highway 5, Western Kern County,  Cuyama Valley,  Kettleman Hills, and San Juan Creek Valley in San Luis Obispo.

In order to ensure these steps towards recovery there needs to be a long-term program to periodically monitor their populations. Monitoring should be conducted annually for at least a 10-year period and periodically after at five-year intervals. (U.S. Fish and Wildlife Service).

What can you do?

Learn about how our government is treating our national monuments and how they pose a threat to endangered species like the Giant Kangaroo Rat. Our government should be protecting our nation and not destroying it. If you agree and think the Giant Kangaroo Rat should be protected through protecting the Carrizo Plains National Monument express your concerns to our government and the Secretary of interior is Ryan Zinke.

Secretary of Interiors Ryan Zinke

Department of the Interior

1849 C Street, N.W.

Washington DC 20240

Other Resources

Stay Updated about threats to the Giant Kangaroo Rat in San Luis Obispo:

•     Carrizo Plains National Monument Threatened                                 
•    The article above states that local politicians are encouraging the community to write to Ryan Zinke

Learn More about the Giant Kangaroo Rat:                 

• California Bureau of Land Management
• Smithsonian National Museum of Natural History

Glossary

• Heteromyid rodent: is a family of rodents consisting of kangaroo rats, kangaroo mice, pocket mice and spiny pocket mice
• Endemic: a plant or animal native or restricted to a certain country or area
• Endangered species: is a species which has been categorized as very likely to become extinct
• Keystone Specie: are species that play a disproportionately large role in the prevalence and population levels of other species within their ecosystem or community.
• Bipedal locomotion: is a form of terrestrial locomotion where an organism moves by means of its two rear limbs or legs.
• High longevity: long life expectancy
• Historical distribution: original location where the species was distributed
• Extant habitat: existing habitat
• Population fragmentation: is a form of population segregation. It is often caused by habitat fragmentation
• Habitat exploitation: the action of making use of and benefiting from the resources of a specie’s habitat
• Dry land farms: crops that needed little rainfall
• Rodenticides: a poison used to kill rodents

Sources

1.      Davison, veronica_davison@fws.gov, External Affairs Divison, Sacramento Fish & Wildlife Office, Veronica. “Giant Kangaroo Rat - Mammals, Endangered Species Accounts | Sacramento Fish & Wildlife Office.” Sacramento Fish and Wildlife, www.fws.gov/sacramento/es_species/Accounts/Mammals/giant_kangaroo_rat/.
2.      “Giant Kangaroo Rat.” Los Padres ForestWatch, 2 Feb. 2018, lpfw.org/our-region/wildlife/kangaroo-rat/.
3.      U.S. Fish and Wildlife Service. 1998. Recovery plan for upland species of the San Joaquin Valley, California . Region 1, Portland, OR. 319 pp.

Author: Amanda Stahler | Student, California Polytechnic State University  

Published: March 5th, 2018