Reptiles and Amphibians

Reptiles and Amphibians — page 5 — EX EW CR EN VU NT LC Blunt-nosed Leopard Lizard Gambelia sila The decline of this attractive lizard dates back to the California Gold Rush of 1849 when parts of its habitat were turned over to agriculture to feed the influx of miners O the the habitat of the blunt-nosed leopard lizard is now restricted to a number of scattered areas in the San Joaquin Valley in California The lizards use the deserted burrows of small mammals for shade shelter and hibernation in winter Although they are diurnal active during the day leopard lizards tend to shelter during the hottest part of the day They are often active at air temperatures of up to 104ºF 40ºC when the soil temperature is about 122ºF 50ºC From September onward the lizards take to their burrows to spend the colder months in a dormant state Leopard lizards have predators which is part of the natural balance but when the lizards are DATA PANEL so spots become indistinct mated females and juveniles develop orange spots males have red coloration in the breeding season Diet Mainly insects other lizards and small mammals Breeding One clutch of 2 6 eggs laid per year Related endangered species None Status IUCN EN Blunt-nosed leopard lizard Gambelia sila Family Iguanidae World population Probably more than 1,000 adults Distribution San Joaquin Valley California Habitat Arid areas often alkaline saline or sandy soils with sparse vegetation rarely above 2,500 ft 800 m Size Length up to 13 in 33 cm Form Slender lizard with long whippy tail blunt nose and spotted throat variable pattern of dark spots and light bars on yellow fawn gray or dark brown background body color lightens with increased temperatures 8 forced into smaller areas by human disturbance and their vegetation cover is destroyed they become more exposed and vulnerable to these predators The Human Threat As the human population increased in the San Joaquin Valley so did agriculture and urban development This inevitably encroached on the habitat of the blunt nosed leopard lizard Further damage occurred as industries developed around the extraction of oil and minerals By 1985 barely 10 percent of the original wild land on the San Joaquin Valley floor had been left undeveloped and in 2007 the lizard was still thought to be in decline The road building and landfill dumping that accompanied development in the valley were also destructive to the lizard’s habitat and the damage to the delicate balance of the desert ecosystem largely ignored Lizards and their habitats were destroyed under construction machinery roads and irrigation ditches fragmented the lizard’s territory Pesticides sprayed on crops also had a detrimental effect on much of the wildlife Oregon Idaho Wyoming Nevada UNITED STATES Utah Colorado California Arizona New Mexico MEXICO Leopard lizards are insectivorous a large part of their diet includes insects so their food supply can be drastically reduced or contaminated by the drift from crop spraying Where the land has been adapted for pastoral farming grazing animals eat the natural vegetation and

Reptiles and Amphibians — page 6 — trample rodent burrows and lizard egg sites They also break the soil surface which can cause soil erosion The removal of natural vegetation through grazing allows nonnative plants to invade eliminating the open spaces preferred by the lizard The threats to the blunt-nosed leopard lizard from continuing habitat destruction were highlighted as far back as 1954 but the species was not listed as endangered by the United States Department of the Interior until 13 years later It was given state listing in 1971 Recovery Plans The first recovery plan for the species was not prepared until 1980 revised in 1985 Since then numerous studies have been carried out including aerial surveys to determine the amount of suitable territory still existing Some areas have been purchased as reserves but lack of funding has prevented this in many areas Conservation is a complex business needing comprehensive studies of numerous aspects ecology population feeding habits breeding and genetic variability Although much information has now been gathered the scattered nature of the remaining lizard sites complicates matters because of environmental The blunt-nosed leopard lizard is active by day and prefers hot dry and sparsely vegetated areas It can run on its hindlegs to escape predators which include snakes birds and mammals variation It may be a long time before all the necessary knowledge is accumulated The blunt-nosed leopard lizard has proved itself to be adaptable often colonizing sites that have been disturbed then abandoned However unless the decline of its habitat and its continued isolation in ever shrinking areas are halted the species may never recover Its survival depends on further land acquisition and the construction of corridors to allow groups to move between fragmented sites so preventing the genetic problems that develop in small populations Its habitat must be protected improved and managed in such a way that the land is only used in a manner compatible with the lizard’s existence This is a tall order given the conflicting interests over land use Recovery of this species will take a very long time it remains to be seen if it will be successful 9

Reptiles and Amphibians — page 7 — EX EW CR EN VU NT LC Pygmy Blue-tongued Skink Tiliqua adelaidensis The pygmy blue-tongued skink once a common lizard was presumed to be extinct since there had been no sightings after 1959 In 1992 however one was found inside the body of a dead snake Surveys carried out in the surrounding region the grasslands of South Australia’s Mount Lofty Ranges revealed a dozen small sites containing pygmy blue-tongued skinks clover has further altered the plant diversity in favor of nonnative species Habitat Destruction At the time when the lizards are most active during the warm months the soil is too hard for them to dig their own burrows As a result they often live in empty spider burrows dug by the spiders during the winter and early spring when the soil is moist and soft Plowing of the land is likely to be particularly destructive to the skink’s survival depriving them of shelter and leaving them exposed to snakes birds and other predators Before Europeans settled in South Australia much of the area was native grassland supporting other reptile species as well as birds and plants Now only about 2 percent of the original grassland is left All pygmy blue-tongued sites are found in the few unplowed areas The undisturbed patches also support rare orchids and other plants butterflies and an endangered bird the plains wanderer Conserving the remaining grasslands will benefit the pygmy blue tongues as well as the other rare fauna and flora Conservation Projects The discovery of an extinct species was exciting and various government bodies museums zoos and universities cooperated in the search for new habitat sites A recovery plan was devised its first task was to study skinks in the wild and in captivity O Although Although less than half the size of the larger blue-tongued skinks familiar to many reptile keepers the pygmy blue-tongued skink is otherwise similar in appearance Its common name comes from the blue tongue displayed by most lizards of the genus Tiliqua However while the pygmy skink’s mouth lining is pinkish-blue its tongue is actually pink The dramatic color combination provides a startling effect that deters attackers The lizard is found in the Mount Lofty Ranges north of Adelaide in South Australia Unfortunately the animal’s preferred habitat is also highly suitable for farming The climate is ideal and the native grassland can be easily plowed Pasture improvement a process of replacing native plant species with agricultural species such as hay grasses and crops like alfalfa and DATA PANEL varies from gray-brown to orange brown with darker flecks along back Diet Insects and some plant material Breeding Gives birth to 1 4 live young per year Related endangered species No close relatives but more than 40 other skink species are listed by IUCN Status IUCN EN South Australia New South Wales AUSTRALIA Victoria Pygmy blue-tongued skink Tiliqua adelaidensis Family Scincidae subfamily Lygosominae World population About 5,500 Distribution North Mount Lofty Ranges southern South Australia Habitat Grassland with tussocks and open areas open woodland Size Length 7 in 18 cm males often slightly smaller than females Form Heavy body with relatively short limbs scales small and smooth Male has larger head than female Color 10

Reptiles and Amphibians — page 8 — A group of pygmy blue tongued skinks was taken to Adelaide Zoo to be studied Specimens were also displayed to increase public awareness of the lizard’s plight After seven years in captivity the colony had not bred It was decided to set up another group in private free from disturbance by the public Little was known about the animal’s behavior and requirements but captive breeding for possible release into the wild was an important part of the recovery plan Pygmy blue tongues are listed under the Endangered Species Protection Act and the South Australia National Parks and Wildlife Act An important task has been to persuade landowners to protect known skink habitat sites on their land There are also several laws that could be enforced to prevent habitat destruction Law enforcement is perhaps the most important task since the habitat is fragile and small in area Some owners of land enclosing sites with good habitat for the species have signed agreements to run their properties as wildlife sanctuaries Other landowners have been eager to sign up though there have been legal problems over grazing rights Two previously unknown sites have also been discovered By early 2000 the situation for the pygmy blue tongued skink had improved An area of native grassland unpopulated by the species but close to its other habitats was made into a conservation park in the hope that it will be suitable for translocations The park could be the first secure home for the animals The pygmy blue tongued skink has a heavy body with relatively short limbs and a fairly short tail and its scales are small and smooth Despite its name the skink’s tongue is in fact mainly pink The total number of blue tongues is difficult to estimate because of their patchy distribution but it may be about 5,500 However the figure is still too low to justify changing the lizard’s Endangered status to Vulnerable Although relatively few populations are unprotected now the lizard will keep its status until larger populations exist in secure habitats One project to increase numbers involves the provision of artificial burrows They are made from wooden tubes that are the same length and diameter as the favored spider hole but less easily destroyed Advising landowners on habitat management such as weed clearance grazing and the use of pesticides is also an important part of the program Community involvement is a high priority and a local school has been involved in studies as part of the plan Despite such efforts the outlook for the pygmy blue tongued skink is by no means certain since funds for wildlife conservation are limited 11

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