Managed grazing in Tulare County helps Valley lizard
By Mark Grossi - The Fresno Bee, 12/10/11
They're an ecological odd couple: cows and blunt-nosed leopard lizards. And their relationship just keeps getting better.
The pairing is playing out at Pixley National Wildlife Refuge in southern Tulare County, where heavy rainfall last winter made grasses grow thicker this year.
Normally that would make life miserable for the endangered lizard. The swift little creature gets hung up in thick grasses and becomes an easy target for predators.
But ranchers buy grazing leases from federal officials and bring cows to the refuge. In short order, the hungry cows munch that grass problem away.
"These grasses are not native to the San Joaquin Valley," said biology professor David Germano of the California State University, Bakersfield. "The little critters aren't adapted to the grasses, so grazing is very important in years after big rainfall."
Blunt-nosed leopard lizards are getting help in their natural habitat in the Pixley Wildlife Refuge by cows grazing off thick grasses, making it easier for the lizards to dodge predators. But some biologists and environmentalists say that cattle grazing damages streams and causes erosion.
It's a successful but unlikely marriage of farming and nature. Along with cities, road building and row crops, uncontrolled cattle grazing was among the reasons the lizard almost went extinct in the Valley.
But managed grazing -- fencing cows in areas and moving them after they eat a lot of the grass -- has become a tool of choice for helping endangered animals and even plants in the southern and western parts of the Valley.
The animals and plants evolved in a desert setting over thousands of years, and they need room to live.
Thick grasslands have developed over many decades since European settlers came to the Valley, bringing crops and vegetation with them, scientists say.
Scientists and land managers in the Valley have realized grazing cows would be a useful line of defense against grassland overgrowth.
"We may still have some of these plants and animals only because the land is being grazed by cattle," said Bryan Cypher, a Bakersfield-based ecologist who works for the Endangered Species Recovery Program at California State University, Stanislaus. "It's the best option we have for dealing with nonnative grasses."
But it's not a popular approach with all biologists and environmentalists, who say that cattle grazing damages streams and causes erosion that harms endangered species. Such uncontrolled grazing has proven to be destructive in California meadows and wetlands.
There is a stigma attached to cattle grazing, especially in the pristine meadows of the Sierra Nevada.
The Valley these days is hardly pristine, Cypher says. In the region's arid southern and western areas, wetlands are limited. Grazing does not create a lot of problems here if cows are properly managed, scientists say.
Grazing clearly works at the Pixley refuge, according to surveys done by the Endangered Species Recovery Program. The latest survey in August concluded the lizard population is "robust."
Federal officials at Pixley refuge said they lease about 5,000 refuge acres to cattle ranchers between November and April each year.
Nick Stanley, deputy project leader, said the grazing creates conditions that help not only the blunt-nosed leopard lizard but also two other protected species, the Tipton kangaroo rat and the San Joaquin kit fox.
Grazing is much better than other options for thinning the grass, which would include burning, pesticides or mowing.
Burning would create too much smoke in the Valley's polluted air. Paying for pesticides or mowing makes little financial sense compared to grazing leases, which create a small income stream for the federal government.
The modest monthly fees are usually several dollars per animal.
Grazing also helps revive vegetation that had been declining as grassland conditions spread over the past century.
Said Stanley, "We're finding that grazing helps the native bunch grasses, like iodine bush and coyote bush."
By Mark Grossi - The Fresno Bee, 12/10/11
They're an ecological odd couple: cows and blunt-nosed leopard lizards. And their relationship just keeps getting better.
The pairing is playing out at Pixley National Wildlife Refuge in southern Tulare County, where heavy rainfall last winter made grasses grow thicker this year.
Normally that would make life miserable for the endangered lizard. The swift little creature gets hung up in thick grasses and becomes an easy target for predators.
But ranchers buy grazing leases from federal officials and bring cows to the refuge. In short order, the hungry cows munch that grass problem away.
"These grasses are not native to the San Joaquin Valley," said biology professor David Germano of the California State University, Bakersfield. "The little critters aren't adapted to the grasses, so grazing is very important in years after big rainfall."
Blunt-nosed leopard lizards are getting help in their natural habitat in the Pixley Wildlife Refuge by cows grazing off thick grasses, making it easier for the lizards to dodge predators. But some biologists and environmentalists say that cattle grazing damages streams and causes erosion.
It's a successful but unlikely marriage of farming and nature. Along with cities, road building and row crops, uncontrolled cattle grazing was among the reasons the lizard almost went extinct in the Valley.
But managed grazing -- fencing cows in areas and moving them after they eat a lot of the grass -- has become a tool of choice for helping endangered animals and even plants in the southern and western parts of the Valley.
The animals and plants evolved in a desert setting over thousands of years, and they need room to live.
Thick grasslands have developed over many decades since European settlers came to the Valley, bringing crops and vegetation with them, scientists say.
Scientists and land managers in the Valley have realized grazing cows would be a useful line of defense against grassland overgrowth.
"We may still have some of these plants and animals only because the land is being grazed by cattle," said Bryan Cypher, a Bakersfield-based ecologist who works for the Endangered Species Recovery Program at California State University, Stanislaus. "It's the best option we have for dealing with nonnative grasses."
But it's not a popular approach with all biologists and environmentalists, who say that cattle grazing damages streams and causes erosion that harms endangered species. Such uncontrolled grazing has proven to be destructive in California meadows and wetlands.
There is a stigma attached to cattle grazing, especially in the pristine meadows of the Sierra Nevada.
The Valley these days is hardly pristine, Cypher says. In the region's arid southern and western areas, wetlands are limited. Grazing does not create a lot of problems here if cows are properly managed, scientists say.
Grazing clearly works at the Pixley refuge, according to surveys done by the Endangered Species Recovery Program. The latest survey in August concluded the lizard population is "robust."
Federal officials at Pixley refuge said they lease about 5,000 refuge acres to cattle ranchers between November and April each year.
Nick Stanley, deputy project leader, said the grazing creates conditions that help not only the blunt-nosed leopard lizard but also two other protected species, the Tipton kangaroo rat and the San Joaquin kit fox.
Grazing is much better than other options for thinning the grass, which would include burning, pesticides or mowing.
Burning would create too much smoke in the Valley's polluted air. Paying for pesticides or mowing makes little financial sense compared to grazing leases, which create a small income stream for the federal government.
The modest monthly fees are usually several dollars per animal.
Grazing also helps revive vegetation that had been declining as grassland conditions spread over the past century.
Said Stanley, "We're finding that grazing helps the native bunch grasses, like iodine bush and coyote bush."
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