Michigan's most endangered species nears extinction in one county
At an idyllic, quiet, tranquil patch of fen and prairie in Oakland County's Springfield Township, a tragedy is unfolding.
It's there that Michigan's most endangered species, the Poweshiek skipperling butterfly, flutters away what may be its last days on Earth.
The brownish-orange, thumbnail-sized butterfly, with a wingspan of only an inch or so, once was fairly common on the North American plains. Now, it's precariously close to extinction: Fewer than 200 are known to remain—in one tiny pocket of the Canadian province of Manitoba, in a solitary area of Wisconsin and the largest remaining number, fewer than 70, in Oakland County, particularly at the Shiawassee Basin Preserve in Springfield Township.
Not long ago, "it was probably the most frequently encountered prairie skipper, a type of butterfly," said Tam Smith, a wildlife biologist with the U.S. Fish and Wildlife Service's Minnesota-Wisconsin field office.
"When folks went out doing surveys for butterflies in the Midwest, they would see the Poweshiek skipperling everywhere," she said. "They paid little attention to it because it was so common."
But starting in the early 2000s, surveyors began to notice an abrupt and rapid decline in Poweshiek populations, Smith said.
"We don't really know for sure what happened," she said.
Leading ideas include the loss of the butterfly's very particular habitat—pristine, never-tilled prairie grasses—to agricultural development. Unlike Monarch butterflies, which migrate across North America to Mexico each winter, Poweshieks are homebodies, sticking to their particular habitat—meaning when it's spoiled, they are in trouble.
Other possible stresses include climate changes such as hotter summers and rainier springs, or the introduction of new pesticides or pathogens, Smith said.
Listed as an endangered species in October 2014, federal, state and other researchers are working to learn not only what happened, but what can be done now. The Fish and Wildlife Service collaborates with partners at the Minnesota Zoo in the Twin Cities suburb of Apple Valley to breed Poweshieks in captivity, and reintroduce them to Oakland County and other locations where they still exist. For the first time this summer, two Powesheiks bred in captivity were released in Oakland County.
"That's really exciting for us," Smith said. "We overcame a lot of obstacles to get to where we're at right now."
Other projects, focused on preserving and improving existing habitat, and attempting to restore lost habitat, are also ongoing, Smith said.
The Poweshiek skipperling has a one-year life cycle, and is in flight only for one month, from mid-June to mid-July, when it breeds and the female lays her eggs, and both the male and female die. A green caterpillar hatches over the summer, growing to only about the width of a penny. It stays in caterpillar form over the winter, when it enters a hibernation-like state.
"Many other prairie skippers will create little shelters out of grasses, down in the dust layer," to get through winter, Smith said. "The Poweshiek doesn't really do that. It spends its winter on top of the grass, exposed to the cold, frost and snow. It has a kind of anti-freeze in its body so it can survive over the winter."
In the spring, the caterpillar awakens, goes into pupa form and emerges as a flying butterfly.
"Flight season is very short—only a couple of weeks," Smith said. "It's a very crammed field season" for scientists "where we're trying to get a lot done."
The researchers head to areas where they know the Powesheiks are mating. "We try to take a proportion of the females that we observe in the field, to take their eggs that they lay during the flight period," she said. "We collect an adult female, take her back in a small, plastic cup with some nectar sources in it that are kept fresh, some grasses."
The female stays in the cup for two or three days, until she lays her eggs. "Then we release her back into the field where she was collected initially," Smith said.
The eggs are then taken back to the Minnesota Zoo, where they hatch within about two weeks. The small caterpillars are then raised in the lab through the summer, fall and winter.
"It was kind of a learning curve for us to learn how to do this," Smith said. "It was the first time it's ever been done.
"Hopefully, their survivorship at a zoo will be greater than we're typically seeing out in the field."
Researchers follow temperature and humidity gauges in Oakland County and "report that data pretty much in real time back to the zoo, so they can mimic what's happening in the field and keep conditions as natural as possible," Smith said.
Springfield Township Supervisor Collin Walls didn't start out a butterfly advocate.
"My first reaction was, 'What the heck is a Poweshiek skipperling?' " he said. "It took me a while to be able to pronounce it." (It's pronounced pow-eh-SHEEK.)
"The more you learn about it, like anything else in nature, or in life, it's part of our heritage—it's part of our ecosystem. It's worth trying to preserve."
The township hired a natural resources manager, Michael Losey, to more carefully focus on the butterfly and the township's other natural attractions. Losey met in the township this spring with personnel from the U.S. Fish and Wildlife Service and the Michigan Department of Natural Resources, as well as counterparts from other U.S. states and Manitoba, to discuss best practices and future courses to help save the Poweshieks.
While the township encourages visitors to the Shiawassee Basin Preserve, it's circumspect about where, specifically, the small pocket of remaining Poweshiek skipperlings are located.
"We had an issue last year—a photographer aware of where they were occurring and being a little too pushy of getting into the habitat while they were mating and laying their eggs," Losey said.
"People who are interested in seeing butterflies in their habitat and interested in butterfly conservation are always welcome to come visit our preserve. But with the Poweshieks, since they are federally endangered, if you're following them to take pictures, and you're trampling their habitat, that could be a negative impact on the species."
Though Oakland County is the Poweshieks' remaining stronghold, that's a relative term. A few years back, as many as 300 of the butterflies could be found locally, Losey said. Now the count is less than 70.
"That's why we're really sensitive about having folks in the habitat where they remain—loving them to death," he said.
Many scientists believe the planet is experiencing its sixth mass extinction in the past half-billion years, the first since the dinosaurs were lost 65 million years ago. Human activities are believed behind the increased pace of extinctions.
Those working to save the Poweshiek skipperling acknowledge that it's on the knife's edge of joining the millions of species lost to the ages.
"Given that worldwide we're looking at an extinction crisis, it's possible we're looking at the same thing in Oakland County in 2018," Losey said. "But it goes to show how much we're still learning about the natural world, how our impacts are maybe contributing to their declines."
Why should people care? Walls said Springfield Township residents consider protecting and enhancing the natural habitat around them as a "major goal" for the enjoyment it brings, the recreational opportunities, and for property values.
The Poweshieks may be a harbinger, Smith said.
"While we are witnessing the decline of this species, we're also seeing the decline of other prairie butterflies, bumblebees. And maybe for similar reasons," she said.
The continued loss of natural pollinators could have major, negative impacts on the agricultural industry worldwide, studies have shown.
"They're kind of a canary in the coal mine. Something happened to cause this dramatic decline in the early 2000s. It's an indicator that something is wrong that we need to pay attention to."
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