Completely aquatic and gilled throughout life. The mudpuppy is the largest member of the genus Necturus which also includes waterdogs. All mudpuppies and waterdogshave bushy external gills, two gill slits, a laterally compressed tail, and four toes on front and hind feet. Adult mudpuppies are 20-49 cm total length. Dorsal coloration varies from rusty brown togray or black with bluish black spots or blotches. A dark stripe occurs on the side of the head, passing through the eye and sometimes extending down the side. The venter is white, gray, yellow, orbrown, sometimes with dark spots. Sexually mature males can be distinguished by the swollen cloaca and pair of enlarged cloacal papillae that project posteriorly (Pfingsten and White 1989; Petranka 1998). Hatchlings are 14-15 mm snout to vent length (21-25 mm total length). Juvenile coloration is quite striking, consisting of a dark middorsal stripe bounded by two lightyellow stripes. A dark band occurs below the yellow stripes. Juvenile color pattern becomes more simlilar to adults with age, beginning at 13-15 cm total length (Shoop 1965; Petranka 1998).
Two subspecies are currently recognized which differ in geographic distribution (see below) and coloration. The mudpuppy (N. m. maculosus, sometimes called the common mudpuppy) isrusty brown to grey dorsally, with a gray venter that ranges from unspotted to densely spotted. The Red River mudpuppy (N. m. louisianensis, sometimes called the Louisiana mudpuppy orwaterdog) is light yellowish brown to tan dorsally, sometimes with a dark dorsal stripe bordered by lighter stripes. The back and sides of the belly have large dark spots or blotches, but the midlineof the venter is light colored with no spots (Conant and Collins 1991; Petranka 1998).
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Canada, United States
U.S. state distribution from AmphibiaWeb's database: Alabama, Arkansas, Connecticut, Georgia, Iowa, Illinois, Indiana, Kansas, Kentucky, Louisiana, Massachusetts, Maryland, Maine, Michigan, Minnesota, Missouri, Mississippi, North Carolina, North Dakota, New Hampshire, New York, Ohio, Oklahoma, Pennsylvania, South Carolina, South Dakota, Tennessee, Virginia, Wisconsin, West Virginia
Canadian province distribution from AmphibiaWeb's database: Manitoba, Ontario, Quebec
Widely ranging through the eastern United States and into southern portions of Canada. From southeastern Manitoba and southern Quebec to northern Georgia, Alabama,Mississippi, and Louisiana. Primarily west of the Appalachians, extending as far west as eastern Oklahoma, eastern North Dakota, and adjacent areas of Manitoba. The Red River mudpuppy isfound in the Arkansas River drainage and adjacent drainages, from southeastern Kansas and southern Missouri to north-central Louisiana. The rest of the range is occupied by the commonmudpuppy (Conant and Collins 1991; Petranka 1998). Mudpuppies inhabit a variety of permanent aquatic habitats including muddy canals and vegetated bays, large streams withfast-flowing water, sluggish streams, resevoirs, and clear, cool lakes. Animals are found under large rocks, logs, and other cover objects during the day, and they may live as deep as 27 m insome lakes (Petranka 1998).
Life History, Abundance, Activity, and Special Behaviors
Mating usually occurs in autumn or winter, but can extend through April. Precise timing varies with location. Courtship has not been described in detail. Oviposition takes placein May or June (Shoop 1965; Petranka 1998). Nests are excavated by females under rocks, logs, boards, and other submerged cover, and eggs are attached single to the undersides ofthese objects. Reported clutch size range from 30 to 140. Hatching occurs 1-2 months after laying, depending on water temperature. Females apparently attend the eggs during development,protecting them from predation (Shoop 1965; Pfingsten and White 1989; Petranka 1998).
Animals foraging on the bottom at night and retreat to burrows and cover during the day. Mudpuppies are active during winter months. Diet includes a range of aquatic invertebrates andvertebrates, including crayfish, annelids, snails, amphibians, fish, beetle and chironomid larvae, mayflies and caddisflies. Predators are poorly documented, but include water snakes (Nerodia).Humans are another source of mortality as fishers frequently discard mudpuppies on land when they are hooked (Pfingsten and White 1989; Petranka 1998)
Trends and Threats
Although many populations seem to be doing well, pollution and siltation are problems for these animals. Populations in Ohio are apparently declining due to these factors (Pfingsten and White 1989; Petranka 1998).
Relation to Humans
Mudpuppies and waterdogs are often seen in the pet trade.
A genetic survey found little divergence between populations of mudpuppies from Massachusetts, Minnesota, and North Carolina (Ashton et al. 1980). Necturus beyeri, N.alabamensis, and N. maculosus are relatively closely related (Guttman et al. 1990).
Ashton, R. E., Jr., Braswell, A. L. and Guttman, S. I. (1980). ''Electrophoretic analysis of three species of Necturus (Amphibia: Proteidae), and the taxonomic status of Necturus lewisi (Brimley).'' Brimleyana, 4, 43-46.
Conant, R. and Collins, J. T. (1991). A Field Guide to Reptiles and Amphibians: Eastern/Central North America. Houghton Mifflin, Boston.
Guttman, S. I., Weigt, L. A., Moler, P. E., Ashton, R. E., Jr., Mansell, B. W. and Peavy, J. (1990). ''An electrophoretic analysis of Necturus form the southeastern United States.'' Journal of Herpetology, 24(2), 163-175.
Petranka, J. W. (1998). Salamanders of the United States and Canada. Smithsonian Institution Press, Washington and London.
Pfingsten, R. A., and White, A. M. (1989). ''Necturus maculosus (Rafinesque). Mudpuppy.'' Salamanders of Ohio. Pfingsten, R. A., and F. L. Downs, eds., Ohio Biological Survey, Columbus, OH, 71-78.
Shoop, C. R. (1965). "Aspects of reproduction in Louisiana Necturus populations." American Midland Naturalist, 74, 357-367.
Written by Meredith J. Mahoney (molge AT yahoo.com), Museum of Vertebrate Zoology
First submitted 2000-07-27
Edited by M. J. Mahoney (2001-05-09)
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