The Conservancy’s Central Coast ecologist
The Nature Conservancy is working with University of California Berkeley researchers and partners at Carrizo Plain National Monument to count and map giant kangaroo rat populations using satellite remote sensing data.
Giant kangaroo rats are the keystone species of Carrizo Plain. A keystone species is like the centerstone in an arch — even though it’s one small stone, it keeps the whole thing standing up.
And when a keystone species is in trouble, the rest of the ecosystem soon will be, too.
That’s why keeping track of this endangered rodent is so critical. Scientists and resource managers base important land management decisions on the size and distribution of each year’s kangaroo rat population, says Conservancy ecologist Scott Butterfield.
The giant kangaroo rat, found only in Central California, is nature’s lawnmower, clipping the grass and creating the preferred low-profile habitat — short, low-to-the-ground plants — of other endangered San Joaquin Valley species, including the kit fox, blunt nosed leopard lizard and antelope squirrel.
About the size of an orange with a tail twice as long as its body, kangaroo rats clip the grasses around their many-roomed burrows or “precincts.”
They then pile up the grass clippings in neat, near perfect circles at the entrance of their burrow, waiting for the grass seeds to cure in the sun before storing them.
A benefit of these mini-compost piles of clippings is an enriched soil. Plants, particularly the California jewel flower, can be three to five times more productive when growing where the stacks have been.
As Butterfield says, “The giant kangaroo rat is the ecosystem engineer of the Carrizo Plain, clipping the grass, creating the burrows and enriching the soil that provides the conditions necessary to support a full suite of endangered species.”
In the past, the Bureau of Land Management tried estimating the kangaroo rat population by trapping them across the Carrizo Plain. This proved too expensive, time consuming and difficult to accomplish each year across their 150,000-acre habitat.
October 26, 2010
Bob Bendick is the Director of U.S. Government Relations of The Nature Conservancy. Prior to taking his current position, he was Vice-President and Managing Director of the ten-state Southern U.S. Region of the Conservancy.