Door to Nature: Seldom Seen Salamanders

The blue-spotted salamander Charlotte holds has moist, slimy skin, as seen by the bits of soil and other debris adhering to its body. Photo by Roy Lukes.

I have heard a muddy puppy give out a yelp or two, but have you ever heard a mudpuppy bark? Supposedly it was thought years ago that these, the largest of Wisconsin’s salamanders, could actually bark. I know some of you have handled mudpuppies while you were ice fishing and that upon removing them from the hook they let out a guttural squeak or two.

During my brief ice fishing days in the Little Sturgeon area, around 1948, it was quite common to reel up what you thought and hoped would be a nice perch, only to find a slimy, foot-long mudpuppy instead. According to the field guides, this cold-blooded, naked creature can attain a length of up to 19 inches. Several very similar but smaller species native to Southern states are called water dogs. Maybe that’s where the belief originated that these backboned aquatic animals could bark.

There is a fascinating spring ritual going on in woodland pools and swamps these mild April nights that very few people ever get to see: the mating of the blue-spotted salamanders. You have the best chance of observing this in areas where the wood frogs, spring peepers and Western chorus frogs will be singing and courting.

Like most other salamanders, these slender-bodied, four to five-inch, earless, long-tailed amphibians with four legs of about equal length make their unerring way to the same secluded bodies of water every year at this time. There, in the water, following some vigorous splashing and various posturing tactics, the male will deposit several tiny sperm sacs, called spermatophores, on the bottom of the pond.

Very soon after this occurs, the female will pick them up with her cloaca, the chamber through which both eggs and waste are passed to the outside. They will be stored in her cloaca until the eggs are laid, which may be several weeks in the future.

The eggs hatch into tiny gilled larvae that will spend perhaps as little as a few months in the water, where they will become excellent predators of, for example, mosquito larvae. Soon they will be transformed into what appear to be tiny salamanders looking considerably like the adults, and then they will leave the water. Some salamander species develop lungs, while others – such as the red-backed salamander, will not. This species will “breathe” through its skin, which is why they have to be constantly slimy on their outer surface.

This red-backed salamander shows its bulging eyes. Photo by Roy Lukes.

The tiny red-backed salamander is one of the most commonly seen of this region. It is around four inches long and as thick as a common lead pencil, with a reddish stripe running the full length of its back. Unlike most other species, this lungless creature does not depend upon being in water at any time during its life cycle.

Mating occurs this time of year, and the six to 14 eggs will be laid sometime in June. A typical location for egg laying will be the inside of a rotting log. The female will remain with the eggs into August, protecting them from predators and keeping them moist until they hatch.

These very small amphibians live in moist woods under leaves, tree bark and logs. Be happy if you discover some of these fascinating animals living on your property. Their presence indicates a healthy woodland. One could expect them to consume sowbugs, crickets, snails, slugs and worms. These salamanders in turn become food for other members of the forest community, such as birds and small mammals.

Studies done by a University of Wisconsin-Green Bay post-grad research student about 12 years ago revealed an unknown abundant population of the rare four-toed salamander in northeast Wisconsin. It was in a State Natural Area, a protected preserve that contains perfect refugia for these four-inch salamanders to exist.

They look a little like the red-backed but have tails that are paler in color than their backs. All other salamanders have five toes on the hind legs but this unusual species has only four. They are active from April through November.

Richard Carl Vogt said in his book Natural History of Amphibians and Reptiles in Wisconsin that in a healthy deciduous forest, one having a good tree canopy and plenty of litter on the floor, nearly 3,000 salamanders can be expected per hectare (approximately two and a half acres). This is twice the biomass of birds in an equal area. This fact again reinforces the importance, as well as the inconspicuousness, of salamanders.

The four most common salamanders in Wisconsin are the mudpuppy, blue-spotted, red-backed and the spotted. I became most familiar with the spotted while I was teaching at the Door-Kewaunee Normal School in the early 1960s. One of my biology students brought in a gorgeous spotted salamander she found in the woods north of Green Bay. It was about nine inches long and black, with a row of yellow spots along each side from head to tail.

The students had set up a wonderful 10-gallon terrarium complete with mosses, lichens, various other tiny native plants, pieces of rotten wood; a perfect environment in which the colorful salamander could live. Earthworms, beetles and other insects didn’t last long when introduced into that spotted creature’s kingdom.

Toward the end of May, just before school let out, we treated our pet amphibian to a couple dozen nightcrawlers, hoping this supply would suffice until September. What a surprise I received upon walking into my classroom that fall to find the spotted salamander as healthy as ever and waiting for more food.

There is a salamander native to the South, the hellbender, that attains a length of up to 27 inches. Another species common to the Smoky Mountains National Park, called the green salamander, is considered to be the only climbing species of the East. This five-inch creature closely resembles the lichens on cliffs it inhabits. In the same general region also lives the pigmy salamander that grows to only two inches.

Even though slimy, creepy-crawly critters turn a lot of people off, you can rest assured that the salamanders of this region will continue to be among the best hiders of all wild animals, and also very important members of many healthy forest food chains.