Bio Facts: Siren, Greater
District of Columbia south throughout Florida and southern Alabama
Shallow, muddy water
Bodies are olive to light gray in color with dark spots on belly, and have one small pair of forelimbs and external feathery gills. Length is 20-30 inches, but can reach lengths in excess of 3 feet. Young have a light lateral stripe that fades as they mature.
Up to 25 years in captivity
In the wild, they eat worms, crayfish, mollusks and some aquatic plants ingested while feeding. In the Zoo they eat pinky mice and salmon pellets.
Greater sirens lay up to 500 eggs that are attached singly or in a layer to underwater plants. Eggs are laid in the spring, and young take several weeks to develop.
Nocturnal by nature, greater sirens spend daylight hours underneath debris, mud or hearty vegetation.
As with most amphibians, the greater siren absorbs oxygen through its skin and external gills. If there is a drought, mucous glands in the skin secrete a thick cocoon over the body to prevent dehydration. When rain returns, water dissolves the mucous and softens the mud to release the siren from the cocoon.
The Greater siren is the second largest salamander. The largest one on record was 38½ inches long.
Sirens are basically salamanders that got stuck in the larval stage of development. Sirens never leave the water, as do other amphibians. They breathe with feathery external gills, and they have lungs.
“Salamander” comes from the Greek word salamandra, which means, “fire.” It was once thought that these creatures loved the warm flames of the fire.
There has been a decline in numbers for salamanders over the past 10-20 years, but scientists just recently began studying this. Some believe that acid rain and snow may be contributing factors, since amphibian skin can absorb toxic substances present in soil and water.
Jacksonville Zoo History:
This species first appears in the Zoo’s animal collection in November 1966.