Forest Preserve District of Cook County, Illinois
Nature Bulletins
Newton Home Page

Introduction and Instructions

Search Engine

Table of Contents

Copyright

Disclaimer

Waterdogs, Hellbenders, Sirens and Congo Eels
Nature Bulletin No. 757   May 23, 1964
Forest Preserve District of Cook County
Seymour Simon, President
David H. Thompson, Senior Naturalist

WATERDOGS, HELLBENDERS, SIRENS AND CONGO EELS
Occasionally a perch fisherman on Chicago's lake front lets out a startled gasp as he pulls in an ugly, squirming creature that looks like something out of a bad dream. It is a foot-long, chunky animal with a flat head, small eyes, a collar of red, bushy gills, four weak legs and a broad tail. The skin -- sickly gray with dark blotches -- is disgustingly slimy.

The Waterdog or Mud Puppy is the most numerous of four species of large salamanders that live in the streams and lakes of the Middle West. Unlike our smaller salamanders which change into an adult form that lives on land, these four remain in a juvenile stage and spend their entire lives in water. As a rule they are active only at night and so secretive in their habits that they are seldom seen except when one swallows a baited hook. Contrary to popular superstitions they are entirely harmless to man. Skinned and fried they are said to have the flavor of frog legs.

In late spring pairs of waterdogs perform a courtship dance and the female sticks about 100 quarter-inch, yellow eggs on the underside of a rock or sunken log. The female guards the nest until the inch-long young hatch some two months later. They grow slowly, finally becoming sexually mature at 7 or 8 years. They have been known to live 23 years in captivity. The diet is mainly crayfish, aquatic insects, worms and fish.

In school and college laboratories generations of zoology students have dissected preserved waterdogs in their anatomy classes. They are particularly well suited for the study of the circulatory system after the arteries have been injected with red and the veins with blue latex. The General Biological Supply House of Chicago prepares and markets about 10,000 of them each year under its scientific name, Necturus.

The Hellbender, so natives along the Ohio and Wabash rivers say, is "a creature from hell -- bent on returning. " Reaching two feet or more in length, it has a stout flattened body, a husky tail, four short thick legs and tiny eyes. It is as wrinkled as a dried prune with loose folds of skin along the sides. Although it may rise to the surface to gulp air into its lungs, it absorbs most of its oxygen through the skin. In September the female lays strings of eggs in a nest scooped in the gravel behind a rock in a fairly fast stream. Here they are guarded and fanned by the male until they hatch in November.

The Giant Salamander of the mountain streams in Japan and China is a near relative of our hellbender. The world's largest living amphibian, it reaches a length of five feet and a weight of 100 pounds. It is known to have survived 55 years in captivity. Now it is raised commercially in Japan as a table delicacy.

The Congo Eel that lives in pools and quiet waters of our southern states is a freak among the salamanders. With a cylindrical, serpentine, muscular body up to thirty inches in length it resembles an eel or a snake but is neither. The oddity about this animal is the ridiculous size of its legs. They are so tiny and weak that they are of no possible use either in walking or swimming. One has to look sharp to see them.

The Siren is another large, eel-like salamander. However, it has useful front legs but no hind legs at all. Like the waterdog it keeps its external gills throughout life. Its favorite habitat is a pond or slough in a river floodplain such as those of downstate Illinois. In early spring the female lays eggs in hollows in the mud bottom; When the ponds dry up, they bury themselves in the muck or retreat into crayfish holes and wait for rain.


To return to the Nature Bulletins Click Here!
Hosted by NEWTON

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Sponsered by Argonne National Labs