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Wildlife Wonders

Today is Mudpuppy Day!

A mudpuppy?? Most people have probably not heard of mudpuppies.  No, it is not a puppy that has rolled in the mud and, unlike what many people might think, they really don’t bark like a puppy, but they do squeak.  So what is a mudpuppy?  A mudpuppy, or as they or called down south a waterdog, is an amphibian and one of the 12 salamanders found in Connecticut.  As people say there are always exceptions to the rule and the mudpuppy is an “exception”.

First, unlike most salamanders that don’t make noises, it is reported that the mudpuppy does make a squeak or grunt when in danger.  Next, the term “amphibian” implies that the animal would spend part of its life in the water and part on land.  Instead, the mudpuppy is fully aquatic, its entire life is spent in the water.  It lives on the bottom of lakes, ponds, rivers and streams and it never leaves the water. 

Amphibians go through metamorphosis…not the mudpuppy.  The mudpuppy is “neotenic”, no metamorphosis of any type occurs.  They retain their larval characteristics – gills and a swimming tail.  The mudpuppy has both lungs and external gills.  Their lungs are mostly used for buoyancy, inflating and deflating like a fish’s swim bladder.  Their bushy, reddish-maroon, external gills are used to breathe and depending on the water temperature and clarity of the water will determine the length of the gills.  Because there is less oxygen in warm, murky water they will have longer gills to get oxygen from the water.  Their skin is also permeable to take in oxygen. 

Mudpuppies are on average about 12 inches long, size varies from 8-17 inches.  They have broad, flat heads, small eyes, and short, rudder-like tails.  They are well camouflaged with green or brownish gray bodies with blue-black spots.  Unlike most salamanders, that have 4 toes on the front feet and five toes on the hind feet, mudpuppies have 4 toes on all feet. 

The mudpuppy’s Latin name is Necturus maculosus.  Necturus means “swimming tail” and maculosus – spotted or speckled.

Most salamanders breed in the spring…not the mudpuppy.  Mudpuppies breed during autumn, September to November and deposit their eggs the following spring.  The female deposits her eggs individually on the “roof” of her hollowed out nest.  Thirty to 200 eggs are attached to the underside of the rock or log.  The incubation is from five weeks to two months depending on the water temperature.  Once again the female exhibits a unique trait among salamanders, she guards the eggs until they hatch.  Newborns in turn will remain with each other and their mothers for a short time. Newly hatched mudpuppies have a broad mid-dorsal brown stripe with yellowish stripes along the side.  They lose the stripes after they second year and grow about 1 1/2 inches each year.  They don’t breed until they are 5 years of age, about 8 inches long.  Their lifespan in the wild is about 11 years and in captivity they have reached 30 years of age. 

They are carnivores feeding on a wide variety of foods including insects, fish, frogs, tadpoles, other salamanders, worms leeches and crayfish.  Insects and crayfish seem to be major staples of their diet.  Their predators are large fish, some mammals and turtles, but because they are so well camouflaged, can secrete a toxin for defense and are nocturnal. Their eggs, rather than the adults, are most at risk of being eaten. 

Their distribution and origins are poorly understood. It is believed they range from southeastern U.S., north to New York, Vermont and Quebec, west to North Dakota.  We do not know if it is a native Connecticut species or introduced.  Much of the literature says it was introduced throughout New England.   The first known specimen collected in Connecticut was collected in 1875 in Middletown. 

One thing we do know about mudpuppies is that they are the “canaries in the coal mines”,  animals used to detect risks to human by providing advanced notice of a danger.  They are indicators of water quality, because of their permeable skin that makes them especially vulnerable to toxins in the water.   In 2015,  the mudpuppy was listed as a Connecticut species of special concern.  Six of Connecticut’s 12 salamanders are listed as endangered, threatened or a species of special concern.  This mirrors what has happened worldwide, where nearly half of salamander species are threatened with extinction.  So although not cute and cuddly like a polar bear or panda, the mudpuppy is also worth protecting.  We especially need to keep our waterways clean and if you ever catch a mudpuppy while fishing, carefully remove the hook and quickly return it to its home and of course, keep learning about all these cool animals!


 Wildlife Fact Sheets – Mudpuppy

Salamanders of Connecticut

PARC – Partners in Amphibian and Reptile Conservation (PARC) Amphibian Week

Amphibians and Reptiles of Connecticut and Adjacent Regions by Michael J. Klemens

Stokes Guide to Amphibians and Reptiles by Thomas F. Tyning

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