Waterdog fish are commonly referred to as mudpuppies; these organisms spend most of their lives underwater and are actually salamanders. Mudpuppies live in waterways around the United States; they occur primarily east of the Mississippi and prefer habitats of streams, rivers and swamplands.
Mudpuppies are one of only several species of salamanders that communicate using vocalization. These species are relatively unattractive in appearance; they have thick brown mottled coats that do not hold great visual appeal but help mudpuppies stay camouflaged when swimming through the water. When provoked or frightened, mudpuppies emit squeaks that resemble the barking of dogs. They are among the largest species of salamander and may reach full-grown heights exceeding 15 inches; there is little variation in size between adult males and females.
These creatures breed in the spring to produce eggs, which hatch into live young mudpuppies. Female mudpuppies lay relatively large clutches or broods of eggs, which they guard until the young hatch. Mudpuppies have bushy red gills on the outsides of their bodies, which develop in the larva stage. These creatures seldom leave water and emerge at night to feed on their prey, which includes crayfish, worms, crustaceans and snails. These creatures have flat heads, stubby legs and wide tails.