Genus/species: Siren lacertina
This is the largest of the sirens and they are known to exceed three feet (.9 m) in length. Sirens resemble overgrown larvae. They have long eel-like bodies and external gills. They are olive to black in color with a lighter belly. Young sirens have a light stripe on their sides, which is lost over time. They lack hind limbs and have relatively weak fore limbs that are not used in swimming or crawling. Their tail is laterally flattened and appears to have a fin around the edge.
Distribution and Habitat
There are only three species of sirens. This species ranges from Virginia south along the Atlantic coast through Florida and into the gulf coast of Alabama.
This fully aquatic siren is found in a greater variety of habitats than the other sirens, including ditches, streams, rivers, swamps, lakes, ponds, and some bays. They spend most of their time buried in mud or sand.
Diet in the Wild
They are effective predators of most aquatic animals, but have been found to eat vegetation occasionally. Carnivorous, they eat crayfish, aquatic insects, worms, snails, and small fish. They hunt at night and spends daylight hours hidden under debris or logs on the bottom. They use a lateral-line system to aid in prey location.
Siren reproduction is a mystery because mating has never been observed. The males lack the gland that secretes spermatophores and the females lack a receptacle in which the sperm is stored. This suggests that they practice external fertilization, however, the female lays eggs singly on widely dispersed aquatic plants. This suggests that the eggs were fertilized before they were laid. Either sirens have internal fertilization unlike that seen in any other salamander or the male follows the female around during egg-laying, fertilizing each individual egg. Scientists do know that the eggs are laid in either late winter or early spring and the larvae hatch about two months later.
It is estimated that they reach maturity in two to three years. Captive sirens have lived to be 25 years of age.
The greater siren in uncommon throughout its range, although it may be common in some locations. It does not seem to be threatened at present. The greatest potential dangers are draining habitats and using aquatic herbicides to clear vegetation from waterways.
Sirens are generally regarded as the most primitive of living salamanders although their ecology and natural history are poorly known. They lack hindlimbs and are completely aquatic throughout their lives, as evidenced by their external gills.
This salamander can aestivate to survive. If the siren’s body of water dries up it can burrow in the mud bottom and secrete a cocoon of mucus and shed skin that covers its body to prevent water loss. All body functions slow down, some by 70 percent, and it can live for more than a year, until the pond refills with water.
When grasped, they commonly emit a yelping sound.