They are among Michigan's most striking native animals, but many Michiganders have never seen one: blue-spotted salamanders.
The small amphibians are inconspicuous because they spend much of their life beneath logs and the soil. But each year, thousands of them march from their underground homes to vernal pools: unique habitats in forests that teem with life for a few months in spring.
When the weather conditions are right in early spring — usually a rainy, warmer night — the salamanders emerge and make their way to the breeding pools. In Presque Isle Park in Michigan's Upper Peninsula, the blue-spotted salamander population has to cross a road to get to and from their breeding pool.
Since 2020, officials in the park have closed Peter White Drive from 8 p.m. to 8 a.m. during salamander migration. The decision was prompted by a 2019 study that found that 400 salamanders were run over by cars during that year's migration.
But a new solution is in the works for the Presque Isle salamander population: migration tunnels beneath the road.
Thanks to a $27,000 grant from the Michigan Department of Natural Resources, the Superior Watershed Partnership and Land Conservancy — a Marquette-based non-profit — will be able to construct the tunnels.
The annual salamander migration in Presque Isle has become an event that draws many observers, so foot traffic is now a concern for the salamanders, said Kathleen Henry, the project coordinator for the Partnership. The organization hopes the tunnels will protect the salamanders from being stepped on; they hope to begin construction in the next year.
"They breed in the spring in what are often termed ‘explosive breeding events.’ So, that’s why projects like this are really exciting because what it means is that you often have a huge percentage of the population moving together on just a handful of nights in the spring to their breeding sites, and things like road mortality can be a really big threat to them," said Katy Greenwald, a professor and herpetologist at Eastern Michigan University.
Greenwald said there are many species of early spring breeding amphibians that depend on vernal pools for reproduction. They include spotted salamanders — a close relative of blue-spotted salamanders — wood and chorus frogs, spring peepers, and Eastern newts. Many of these species occur alongside populations of blue-spotted salamanders.
Greenwald said the salamanders typically stay within 300 meters of their breeding pools. For the salamanders, it’s a long journey; for salamander enthusiasts, the spring migration affords the chance to see something marvelous nearby.
“You don’t have to travel so far to be involved in a project or important conservation. I just really encourage everyone to look to their own community and see, you know, what little critters or creatures might need assistance with habitat fragmentation, and you can implement these sorts of things on a local level wherever you are,” Henry said.
