Black toad
Encyclopedia
The black toad also known as the Inyo toad or Deep Springs black toad, is a true toad
that lives only in scattered oases in the Deep Springs Valley
of Inyo County, California
. In fact, its scientific name
, Bufo exsul means "exiled toad," which refers to its species' isolation in a tiny spot in the high desert wilderness of the Californian Great Basin
.
.
continues a program to care for the wild population of this species, and owns much of the land where its habitat is found. Livestock grazing has occurred in much of the toad habitat for more than one hundred years, and grazing, vegetation management, and irrigation have been suggested as possibly increasing the suitable habitat for the species, which breeds in otherwise comparatively rare open water. As noted in the 2006 IUCN Red List the population of this species was reported to be more or less stable in the early 1970s, and no significant change was reported in 1990 or 1999. The population at Antelope Springs was once reported to have died out , but was found by researchers in 2003 , and is now apparently thriving where vegetation has been maintained in a suitable state. In 1977 it was estimated that there were more than 80,000 individuals in the population.
The toad's primary habitat is watercourses, irrigation ditches, and marshes (grass, sedge, dwarf bulrush, and watercress) formed by waterflow from springs, surrounded by cold desert steppe. Adults are more aquatic than other toad species in California, and breed in shallow marsh and pond waters. The toads retreat to rodent burrows or other refuges in winter . At present, there do not appear to be any major threats to this species. However, potential future threats might include habitat destruction from changes in irrigation schemes or other factors resulting in water table alteration, well-intentioned but non-scientifically based conservation efforts, changes in water availability, recreational vehicle use, collection by humans, changes in grazing regimes and predation by introduced fish. Anaxyrus exsul. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.1.. Downloaded on 11 May 2010. Other desert toads in nearby areas have done well, and even thrived, with more active management. Bufo exsul adults prefer habitats with short plant cover and unobstructed access to still or slowly flowing water . In recent years, fencing some springs to exclude cattle has resulted in an overgrowth of vegetation requiring hand cutting to keep the habitat accessible for toads. The toads have been able to maintain a fairly stable population regardless of changes in agriculture and grazing practices over the past 20 years.
True toad
Bufonidae is the family of the true toads, members of the order Anura . They are the only family of anurans all members of which are known as "toads." The bufonids now comprise more than 35 genera, Bufo being the most widespread and well known.-Characteristics:True toads are widespread and occur...
that lives only in scattered oases in the Deep Springs Valley
Deep Springs Valley
Deep Springs Valley is a high desert valley in the Inyo-White Mountains of Inyo County, California. It is east of the Owens Valley and the Sierra Nevada mountain range, and south of Fish Lake Valley, Nevada, near the California-Nevada state border....
of Inyo County, California
Inyo County, California
-National protected areas:* Death Valley National Park * Inyo National Forest * Manzanar National Historic Site-Major highways:* U.S. Route 6* U.S. Route 395* State Route 127* State Route 136* State Route 168* State Route 178...
. In fact, its scientific name
Binomial nomenclature
Binomial nomenclature is a formal system of naming species of living things by giving each a name composed of two parts, both of which use Latin grammatical forms, although they can be based on words from other languages...
, Bufo exsul means "exiled toad," which refers to its species' isolation in a tiny spot in the high desert wilderness of the Californian Great Basin
Great Basin
The Great Basin is the largest area of contiguous endorheic watersheds in North America and is noted for its arid conditions and Basin and Range topography that varies from the North American low point at Badwater Basin to the highest point of the contiguous United States, less than away at the...
.
Physical description
The toad's black skin is covered in white and tan speckles and it sports a white midline down its spine from head to rump. Adults are approximately 5 centimetres (2 in) in length. They are active during the warmer months and overwinter underground near their native springs. This species walks rather than hops, and never strays far from water. Male black toads do not have vocal sacs and do not make a real advertisement call, but rather a small chirping noise as a territorial call around other males; much like its close relative the western toadWestern toad
The Western toad more commonly known as is a large toad species, between 5.6 and 13 cm long, of western North America. It has a white or cream dorsal stripe, and is dusky gray or greenish dorsally with skin glands concentrated within the dark blotches...
.
Conservation status
The habitat of the black toad is relatively intact, however it is still considered a vulnerable species because although it is abundant within its habitat, the black toad has one of the most limited ranges of any amphibian. Deep Springs CollegeDeep Springs College
Deep Springs is a private, all-male , alternative college in Deep Springs, California, in the United States. A two-year college, the institution currently aims for a student body size of 26, though the number is occasionally lower...
continues a program to care for the wild population of this species, and owns much of the land where its habitat is found. Livestock grazing has occurred in much of the toad habitat for more than one hundred years, and grazing, vegetation management, and irrigation have been suggested as possibly increasing the suitable habitat for the species, which breeds in otherwise comparatively rare open water. As noted in the 2006 IUCN Red List the population of this species was reported to be more or less stable in the early 1970s, and no significant change was reported in 1990 or 1999. The population at Antelope Springs was once reported to have died out , but was found by researchers in 2003 , and is now apparently thriving where vegetation has been maintained in a suitable state. In 1977 it was estimated that there were more than 80,000 individuals in the population.
The toad's primary habitat is watercourses, irrigation ditches, and marshes (grass, sedge, dwarf bulrush, and watercress) formed by waterflow from springs, surrounded by cold desert steppe. Adults are more aquatic than other toad species in California, and breed in shallow marsh and pond waters. The toads retreat to rodent burrows or other refuges in winter . At present, there do not appear to be any major threats to this species. However, potential future threats might include habitat destruction from changes in irrigation schemes or other factors resulting in water table alteration, well-intentioned but non-scientifically based conservation efforts, changes in water availability, recreational vehicle use, collection by humans, changes in grazing regimes and predation by introduced fish. Anaxyrus exsul. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.1.
External links
- Bufo exsul at CalPhotos
- Black Toad Band