Tag: salamanders

Larvae of the Tiger Salamander

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Eastern Tiger Salamanders (Ambystoma tigrinum) are among the many interesting creatures found in the Suffolk County Boglands of Long Island, and these are a coastal plain lineage, subspecies (Ambystoma tigrinum tigrinum). They are known as Mole Salamanders, which spend most of their adult lives underground in burrows, except for when they emerge on rainy nights in the late winter, around February or March, to breed and lay their eggs in small ponds. Each female lays an egg mass that can contain up to 100 eggs which hatch in about two to six weeks, from late March to April depending on the water temperatures. The larvae are aquatic and small, measuring around a half an inch at hatching. As they begin to feed, they grow larger, and go through a metamorphosis growing limbs and transforming to terrestrial adults in a few months, usually by July, when they crawl out from the ponds and disperse, to begin their dark, subterranean lives underground.

These specimens seen in the photographs are of the aquatic larval stage, who some people call “water dogs”. Swimming through the water, with large, broad heads, and feathery gills ravenously eating anything that they can fit into their mouths, sometimes even the smaller members of their own species. Small crustaceans, insect larvae, molluscs, leeches, frog tadpoles, and the larvae of other salamander species are some of the many other things that they will eat as well. Their juvenile existence in the pond also consists of avoiding being eaten by predators such as larger aquatic insects, frogs, snakes, and birds. It is a highly competitive struggle for survival that these creatures are destined for, with only a small percentage of them ever reaching adulthood. Their natural predators may present formidable dangers for the salamanders, but it is the human influences that are the greatest threat to their long-term survival. Long ago, it is thought that all vernal ponds with sandy soils on Long Island once had Tiger Salamanders breeding in them. But today it is estimated that only about 90 ponds with breeding populations are left, and of those only about 13% are considered to be of excellent viability. Increasing development and pollution of their habitats are eradicating these strange and rarely seen creatures, at a rate that could unfortunately see them disappear from our local natural wildlands forever.

 

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