By Michael Price
Most folks are very familiar with the two most common types of amphibians that reside in this state. Nearly everyone has heard a frog calling, or seen a toad in their own backyard. Yet most people are not aware of a foot-long, 4-legged and tailed amphibian that dwells here as well, and that is the Barred Tiger Salamander.
The Barred Tiger Salamander (Ambystoma tigrinum mavortium) belongs to a genus of salamanders that are categorized as Mole Salamanders. This genus has five representatives in Texas, and this particular species has the most extensive range of the faction. This distinctive species occurs in the northern extensions of the Edwards Plateau northward throughout the entire Texas Panhandle and westward throughout the entire Trans-Pecos region. It is in these eco-regions that it resides almost exclusively near semi-permanent bodies of water, primarily in areas of rocky or sandy grasslands. Moderately or heavily vegetated cattle watering tanks and stock ponds (ones that are not stocked with carnivorous fish) are often utilized as breeding areas. In the Texas Panhandle, ephemeral playa lakes are heavily exploited as breeding sites, especially playas that have been unaltered by farmland or industry.
As the family name implies, this group of salamanders is well suited to living life underground, much akin to moles. It rarely makes an appearance above ground, typically after heavy deluges of spring and summer rains, although occasional specimens may be surface active after sufficient winter rainfall. Its propensity to remain underground makes this creature a common, but rarely observed treasure, even by those who are looking for it.
The old adage “everything is bigger in Texas” holds true with this species. Whereas other members of this clan are undersized, this type is the largest terrestrial salamander species in the eastern United States. Adults can range in size from seven to nine inches, although foot-long individuals are not uncommon. The water-dwelling larvae often achieve a total length of six inches or so.
This impressive salamander variety is usually, but not always, stunningly colored. The dorsal coloration is typically black, and most individuals have a series of bright yellow bars and dots that are painted along the backside, the reason that it bears the common name Tiger Salamander. In some individuals, the yellow is the predominating color, giving the animal an astonishing appearance. The water-bound larvae are generally colored a mediocre olive-brown with large, limb-like gills on either side of the head. Many larvae are sold by bait stores to game fisherman.
The breeding cycle of this magnificent amphibian is a bit unusual, not only for the time of year that it generally takes place, but also in the reproductive habits as well. Unlike most other arid-living amphibians, who wait for the summer rainy season to emerge to reproduce in shallow pools, this unique amphibian will often congregate in areas of water during the winter months when the air temperatures are considered to be too low for other “herptiles” to be active. I have observed many specimens in temperatures too cold for me – which just happens to be any temperatures below 50 degrees!
Males will enter the breeding pools first, awaiting the arrival of the females. Once the females arrive, the males will begin to deposit spermatophores (a small capsule that containing spermatozoa). Once the males make the deposit, they will then begin to nudge a receptive female to “pick up” the capsules in their cloaca.
The females will then proceed to lay the large fertilized eggs, numbering up to 300, in clumps of vegetation. The larvae that hatch will attain a total length between 4 and 6 inches before they begin the transformation into land-dwellers. This process, depending on how long it takes to achieve this size, may take months or sometimes years. On rare occasions, the larvae never achieve the appropriate size and will remain in the larval state permanently.
Although they are rarely seen, the Barred Tiger Salamander is very widespread and the population densities are somewhat stable across their range. The biggest threat, at least in the Panhandle, is the decimation of the playa lakes, their primary breeding sites.