Western Lesser Siren
Fully aquatic; known only from the Indiana portion of the Kankakee drainage, with current records only from Jasper County.
Description: The lesser siren is an unusual creature, elongated and eel-like except with two small front legs, and bushy external gills. Total length is 7 to 27 inches (18 to 68.6 cm). Above, the coloration is brown, olive, or almost black; the underside is gray. Small scattered black specks may be present.
Distribution and Status: The lesser siren is known from a few records, most of them old, in the Kankakee River drainage of Indiana. The closest known surviving population is in northern Jasper County, a little outside of the area covered by these accounts. One of the older records is documented by a large specimen in the collection of the Field Museum, taken near Hebron in Porter County. Some potentially excellent habitat exists near the Kankakee River in Illinois, between Momence and the state line; my only attempt to sample there was hampered by high water.
Habitat: The lesser siren inhabits a variety of permanent and semi-permanent aquatic situations, with many specimens taken in ditches and nearby ponds. The vicinity of the known localities would have once included a mix of wooded floodplain with swamp forest and oxbox ponds, and more open marshes. Much of that area has been channelized and drained today.
Minton (1972) described the habitat as "warm, quiet, shallow water with a mucky bottom and plentiful aquatic vegetation."
Phenology: There is no specific Chicago region information on life history. Populations in southern Illinois and Arkansas breed in the spring, with eggs reported in early April. Larvae apparently reach maturity after about two full growing seasons, possibly longer (Minton 1972) although there is little change in appearance, habitat, or behavior in this fully aquatic species.
Congregations of adults have been reported in culverts in winter. During drought the lesser siren burrows into the mud, and is apparently able to survive until rains once again raise the water level.
Minton, S. A., Jr. 1972. Amphibians and Reptiles of Indiana. Indiana Academy of Science, Monograph No. 3.