Tiger Salamander
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{{Taxobox | color = pink | name = Tiger Salamander | image = Tigersalamander_sm.jpg | image_width = 200px | regnum = Animalia | phylum = Chordata | classis = Lissamphibia | ordo = Caudata | familia = Ambystomatidae | genus = Ambystoma | species = A. tigrinum | binomial = Ambystoma tigrinum | binomial_authority = Green, 1825 | subdivision_ranks = Subspecies | subdivision =
- A. tigrinum tigrinum
}} The Tiger Salamander (Ambystoma tigrinum) is a species of Mole salamander. The proper common name is the Eastern Tiger Salamander, as to differentiate from other closely related species.
Eastern tiger salamanders are large, with a typical length of 6-8 inches. They can reach up to 13 inches in length, particularly neotenic individuals. Adults are usually blotched with grey, green, or black, and have large, lidded eyes. They have short snouts, thick necks, sturdy legs, and long tails. Their diet consist largely of small insects and worms, though it is not rare for an adult to consume frogs and baby mice
Adults are rarely seen in the open and often live in burrows. Tiger salamanders are almost entirely terrestrial as adults, and usually only return to the water to breed. Like all ambystomatids, they are extremely loyal to their birthplace, and will travel quite some distance to reach it. However, a single tiger salamander has only a 50% chance of breeding more than once in its lifetime. Males nudges a willing female to initiate mating, and then deposits a spermatophore on the lake bottom. The female picks up the packet and deposits the now-fertilized eggs on vegetation. Large-scale captive breeding of Tiger salamanders has not been accomplished, for unknown reasons.
The larvae are entirely aquatic, and are characterized by large external gills and a prominent caudal fin that originates just behind the head. Limbs are fully developed within a short time of hatching. Larvae come in two types - cannibalistic and non-cannibalistic. High larvae density is said to trigger the cannibalistic phenotype, which has a much larger head than normal. Some larvae, especially in seasonal pools and in the north, may metamorphose as soon as feasible. These are known as small morph adults. Other larvae, especially in ancestral pools and warmer climated, may not metamorphose until fully adult size. These large larvae are usually known as waterdogs, and are used extensively in the bait and pet trade. Some populations may not metamorphose at all, and become sexually mature while in their larval form. These are the neotenes, and are particularly common where terrestrial conditions are bad.
Tiger salamander adults are also often sold as pets, or used in research. Nearly all such salamanders are wild-caught.
The California Tiger Salamander (Ambystoma californiense), the Barred Tiger Salamander (Ambystoma Mavortium), and the Mexican Tiger Salamander (Ambystoma velasci), were all once subspecies of tigrinum, but are now considered separate species. Genetic studies made it necessary to break up the original tigrinum population, even though there is some hybridization between groups.
In 2005, Illinois voters chose the Eastern Tiger Salamander as the state amphibian.
External links
- Tiger Salamander facts - Wild Animals Online encyclopedia
de:Tigersalamander it:Ambistoma tigrinum nl:Tijgersalamander pt:Ambystoma tigrinum