Blunt-nosed leopard lizard

Gambelia sila

  • Endangered, federal Endangered Species Act
  • Endangered, California Endangered Species Act
  • Fully Protected Species, California Department of Fish & Game

Photo by Gary Nafis

The blunt-nosed leopard lizard is a relatively large lizard with a body length ranging from 3-5 inches and a regenerative tail that is normally longer than the body; the entire lizard’s length can approach a foot long! As its name suggests, the leopard lizard has large dark spots (as well as cream-colored bands) running the length of its body. The blunt-nosed leopard lizard’s range occurs near (and possibly in) the Los Padres National Forest in the upper Cuyama Valley, and here it converges with the range of the long-nosed leopard lizard. Besides the different snout lengths, these two species exhibit additional biological, ecological and behavioral differences, though they will hybridize (mate and create a blending of the species). This makes the area of the forest where these species meet particularly important, especially from a genetic and species conservation standpoint.

Natural History

Female with bright orange plumage during mating season. Photo by Chuck Graham

The blunt-nosed leopard lizard is found only in California, in the San Joaquin Valley and nearby valleys and foothills. The Carrizo Plain National Monument is one of the largest remaining population centers for the lizard; they occupy more than 87,000 acres of the national monument and are most abundant on the Elkhorn Plain in the southern portion of the Carrizo Plain.

Insects–mostly grasshoppers, crickets, and moths–comprise the major portion of their diet, but they are opportunistic and will feed on whatever prey they can get their claws on. Blunt-nosed leopard lizards use small mammal burrows for shelter from predators, refuge from extreme temperatures, and dormancy periods. Typically these include abandoned ground squirrel tunnels and occupied and abandoned kangaroo rat tunnels. These lizards are active during the warmer months of the year, and they hibernate in the winter. The breeding season is initiated in April and lasts through June. Male and female pairs are commonly seen at this time and the female will exhibit orange markings on her underside.

Leopard lizard heading into a burrow. Photo by Gary Nafis

Threats

The former range of the blunt-nosed leopard lizard encompassed the floor of the San Joaquin Valley and Sierra foothills. The species also occurred on the Kettleman and Carrizo plains, and in the southeastern Cuyama Valley in San Luis Obispo, Santa Barbara, and Ventura counties.

Since the 1870s and the advent of large-scale irrigated agriculture in the San Joaquin Valley, more than 95 percent of the original populations of blunt-nosed leopard lizard have been destroyed. This dramatic loss was the cumulative result of loss of habitat due to such activities as cultivation, construction of facilities related to oil and natural gas production, pesticide applications, off-road vehicle destruction, and general development. This dramatic decline in its available habitat, and degradation of existing habitat, prompted state and federal biologists to classify the lizard as “endangered.”

On the Los Padres and surrounding habitat of the Cuyama Valley, possible threats include activities that remove habitat or crush burrows or individual lizards—such as oil drilling, off-road vehicles, and livestock grazing.

Conservation

Photo Gary Nafis

The blunt-nosed leopard lizard was one of the first species protected under federal law, listed as endangered by the U.S. Department of the Interior in 1967 (before the modern-day Endangered Species Act). It was also listed as a “fully protected species” by State of California in the 1960s and was subsequently listed as endangered in 1971. The “fully protected species” laws were enacted prior to the California Endangered Species Act, and the federal Endangered Species Act, to prohibit hunting, catching, or harvesting of specific threatened species.

To help bring the blunt-nosed leopard lizard back from the brink of extinction, federal biologists prepared a recovery plan in 1980 and it has gone through several revisions since. In early 2010, biologists completed a Five-Year Review looking at the status of the species and identified the need for additional conservation efforts, including habitat and population surveys, habitat management, land acquisition, and development of management plans for public lands. The status review also identified essential habitat areas –five areas where 6,000 acres or more require protection essential for the survival of the species; the Carrizo Plain was one of these.

No current overall population estimates are available for blunt-nosed leopard lizards. However, many large-scale surveys have taken place. Design and implementation of a range-wide population monitoring program is still needed, as is protection of additional habitat in key portions of their range.

ForestWatch will continue to monitor blunt-nosed leopard lizards on the Los Padres National Forest and the Carrizo Plain National Monument, and will work with stakeholders to safeguard their habitat from further degradation.