Spring's the time for spotting salamanders on the move
April 24, 2014
Spring bird migrations can be an extraordinary sight, and state game and management areas - especially those that encompass wetlands - are popular destinations for bird watchers who wish to observe the waterfowl and shore birds that wing their way north from wintering climes. There's another significant wildlife migration happening right now, one that can be just as spectacular but often flies below the radar.
Michigan's salamanders are on the move.
"Salamanders are kind of a mystery," said Tom Goniea, the fisheries biologist who oversees herptiles (reptiles and amphibians) for the Department of Natural Resources. "They're mostly nocturnal or subterranean. Springtime is when people run into them the most because that's when they're moving over land to breeding pools."
Most Michigan salamanders are land-dwelling species that breed in the water, often in small, temporary wetlands. After their eggs hatch out, the creatures go through a larval stage until they mature and morph into terrestrials.
On warm, rainy spring nights, salamanders make their way from their terrestrial haunts to the wetlands where they'll reproduce.
Salamanders are amphibians - cold-blooded vertebrates that are typically aquatic (breathing through gills) when young, but become terrestrial (breathing by lungs or through their moist skin) as adults.
Michigan is home to about 13 species of salamanders that vary widely in life cycles. Perhaps the most well-known, the mudpuppy, is a fully aquatic species. The red-backed salamander is fully terrestrial, laying its eggs on land. The western lesser siren is a primarily aquatic species - without rear legs - that has been documented in Allegan and Van Buren counties, but has not been reported in more than 30 years.
Of the remaining species, many are called "mole salamanders" because they utilize burrows. Only tiger salamanders construct their own burrows, while spotted, blue-spotted and small-mouthed (a state endangered species) salamanders utilize burrows forged by other creatures.
Marbled salamanders breed in the fall on land and lay their eggs in depressions under logs or leaf litter. When the depressions fill with water from fall rains, the eggs hatch in about two weeks. If the depressions don't flood, the eggs will remain fallow until the next spring. Marbled salamanders have not been observed in Michigan for many years.
Four-toed salamanders lay their eggs in moss, leaf litter or rotting wood that overhangs a wet area. When the eggs hatch, the larvae drop into the water where they develop, metamorphosing into adult form in about six weeks.
Red-spotted newts exhibit an unusual, almost reverse life cycle. After hatching out in water, they live on land for three to seven years - when they are called efts - and then return to an aquatic environment.
David Mifsud, a private-sector biologist and self-described "salamander junkie," said most, if not all Michigan salamander species are in decline. "Almost all of the salamanders are in the state wildlife action plan and are included on the list of species of greatest conservation need."
The decline in Michigan salamanders can be traced to a number of factors, Mifsud said, though habitat loss and fragmentation (a decrease in habitat type or a breaking-up of remaining habitat into smaller, more isolated pieces) are chief among them. Salamanders are sensitive to storm-water run-off, invasive plants and chemicals.
Mifsud is optimistic about the future of salamanders, though "it's going to take recognizing them as valuable parts of our ecosystem, not as secondary players," he said. "The attitude is gradually changing - from my perspective, things are getting better in terms of awareness."
Mifsud's company - Herpetological Resources and Management, LLC - administers the Michigan Herp Atlas in partnership with the DNR.
"We now have a quarter-million records as part of the Michigan Herp Atlas database," he said. "It's an incredibly effective way for researchers, regulatory agencies and citizen/scientists to contribute."
Michigan's herptiles are managed by the DNR's Fisheries Division, largely by happenstance.
"Prior to 1988, there was no regulation of reptiles and amphibians in this state," Goniea said. "We had a fisheries biologist at the time who was concerned about the decline in turtles he'd been seeing, and he spearheaded the charge that we needed to begin managing them.
"When the DNR received regulatory authority from the Legislature, it was decided that Fisheries Division should regulate herptiles because we had a fisheries biologist interested in them."
It's a natural relationship, Goniea said.
"Amphibians are largely aquatic," he said. "They spend much of their time in water. All of our turtle species except for one are aquatic. A good portion of the other states regulate reptiles and amphibians under a fishing license."
In Michigan, herp collectors may have up to 10 frogs, toads and/or salamanders in possession from the last Saturday in May through Nov. 15, though there are a number of species of concern that may not be taken.
"For a long time frogs and salamanders were used by fishermen as bait, but with the advancement of artificial baits, particularly plastics, the use of those species as bait is completely unnecessary," Goniea said. "In many ways, Michigan is far ahead of a lot of states in the way we value and protect these animals."
Instead of collecting them, folks should just enjoy them, Goniea said.
"On a warm spring evening in April, take a flashlight and an inquisitive child out to a wet area, and see what you see. You may have to look hard. It takes a while, but there a variety of salamanders, frogs and toads out there to explore."
For more information on salamanders and other Michigan herptiles, visit www.miherpatlas.org.