The misunderstood mudpuppy

Sorting out the fact and fiction about Michigan’s largest, fully aquatic salamander.

Mudpuppies are Michigan’s largest, fully aquatic salamander. Often referred to as ‘bio-indicators’ because they are sensitive to pollutants and water quality, these salamanders act as an early warning system for environmental problems but are often misunderstood.

While researching mudpuppies and using information from National Geographic, Michigan Department of Natural Resources and herpetologist David Mifsud of Herpetological Resource Management, I learned many people hold common beliefs about mudpuppies that are not true. Below I’ll sort out some of the fiction and the facts:

FICTION VS. FACT

Mudpuppies are a type of fish. Mudpuppies are actually an amphibian and although they have lungs and can gulp air they rely on their feathery red external gills for oxygen. Mudpuppies that are thrown on the ice by anglers will revive in the spring when the ice melts. Unfortunately if a mudpuppy freezes it will die. When thrown on the ice mudpuppies will eventually suffocate or freeze to death. Mudpuppies eat so many fish eggs that they decrease sport fish populations. Their diet is mostly crayfish, insect larvae, snails and small fish (including invasive round gobies). There is no evidence that they impact fish populations, and they more likely benefit them by helping control nonnative species. Mudpuppies are not protected in Michigan and can be collected all year round. According to MDNR, mudpuppies are a regulated species in Michigan. They have a closed season from November 15 to May 15 which is when most people catch them while fishing. When you catch a mudpuppy, please put them back. Mudpuppies are blind and are not good hunters. Mudpuppies are not blind, but their eyesight is limited. They rely on a keen sense of smell to find their prey. Mudpuppies are abundant and do not need any further protection. Historically, mudpuppies were much more common. Habitat loss, reduced water quality, sensitivity to lampricides, and collection/persecution have significantly reduced this species in Michigan. Currently this species is identified by the MDNR Wildlife Action Plan as a Species of Greatest Conservation Need. Mudpuppies abandon their eggs once laid. Female mudpuppies not only protect their eggs until they hatch but will also guard the nest while the young emerge and disperse. Anglers who hook them should cut the line because they are poisonous. Although slimy, mudpuppies are not poisonous. Anglers should gently remove the hook and return them to the water.

Other interesting facts about mudpuppies:

Mudpuppies mate in late fall but the females do not lay their eggs until the following spring.

Mudpuppies have no scales and their skin is very slimy.

Females usually lay 50-100 eggs in cavities or under rocks.

Eggs hatch 1-2 months after being laid.

Mudpuppies can live for more than 20 years and can take up to 10 years to reach sexual maturity.

Mudpuppies are also called waterdogs because of the barking sound they sometimes make.

Michigan Sea Grant is working with the University of Michigan, Eastern Michigan University, and Herpetological Resource and Management in collaboration with other partners such as the United States Geological Survey, United States Fish and Wildlife Service, Department of Natural Resources Fisheries Division, and Belle Isle Aquarium, to look at the conservation and management of mudpuppies in Michigan. The partners are asking the public to contribute all amphibian and reptile observations to the Michigan Herp Atlas to help better protect and conserve Michigan’s biodiversity! You can also enter data now using the new Herp Atlas smart phone app.