EAST LANSING, MI – Michigan and other parts of the central Midwest may present the best opportunity for monarch butterflies to fight extinction in the face of climate change.
New research shows that large parts of North America’s current natural summer frost range could become inhospitable for the beloved insect, which was only recently classified internationally as an endangered species in the coming decades. Climate change is expected to eventually cause air temperatures to rise and rainfall to decrease to degrees damaging to frosts, although a recent study shows that parts of the central Midwest may provide the last suitable habitat.
That means conservation efforts can be focused in that region — including southern Michigan and Ontario, and northern parts of Illinois, Indiana and Ohio — for the best chances of saving the critical pollinator insect.
“There are areas where we could be climate refuges, areas that could potentially be better for monarchs, and we could really focus conservation action there,” said Elise Zipkin, an associate professor at Michigan State University who was one of the scientists. who recently published a study on the decline in monarch butterfly populations due to climate change.
The high-tech climate modeling project showed that predicted changes in breeding season conditions are likely to lead to a sustained decline in the general monarchy. Statistics show that between 1996 and 2014, the number of eastern monarch butterflies decreased by more than 80%.
However, this new study predicts that there could be an increase in the number of colorful butterflies seeking refuge in certain parts of the central Midwest; it could result in more monarchs in those areas than in the summers now.
Zipkin explained that this is because areas in the Upper Midwest like Minnesota, Wisconsin and Northern Iowa are expected to become too hot and dry for native milkweed to thrive, while parts of the Southeastern Midwest are expected to receive much more rain than now. Milkweed species are the only host plants for monarchs to lay their eggs and later for hatched caterpillars to consume.
Among those expected extreme weather events is the central Midwest, where Zipkin said conditions could remain just right to bolster monarch numbers and provide the last, best chance to save the species.
“There’s a good place that might get better for monarch butterflies in the future — areas that don’t get too hot and also stay relatively wet,” she said.
The project’s extensive datasets and climate models predicted exactly which provinces are most likely to provide the best possible habitat in the face of climate change. Researchers ran four scenarios for the next 80 years with varying degrees of reduction in carbon emissions.
“These projections let us look at how monarch populations in the Midwest will change and say, ‘Here they’ll probably do a little better, here they might do a little worse,'” said Erin Zylstra, lead author of the new report. and a former postdoctoral researcher at MSU’s Zipkin Quantitative Ecology Lab.
She explained how this research can help communities establish targeted conservation efforts with milkweed and other native plants and habitats.
“If we can find the places where the impacts of climate change are not expected to be as bad, those could become the areas where we invest our resources,” Zylstra said.
Monarchs are known for having one of the longest annual migrations of any insect species. Eastern monarch butterflies spend the winter in the mountainous regions of central Mexico, but travel to the northern United States and parts of Canada. Western monarchs spend winters on the California coast and summers in several states west of the Rocky Mountains.
The dramatic decline in monarch butterfly populations is largely attributed to habitat loss, climate change and the widespread use of pesticides for agriculture.
The U.S. Fish and Wildlife Service has not listed monarch butterflies under the Endangered Species Act, although several environmental and conservation organizations claim they should be included on the list. The agency said in 2020 that other “higher-priority actions” prevented the monarch from being classified as endangered or threatened, but that the butterfly would become a “candidate” for future inclusion of endangered species.
Yooper makes cactus discovery in the heights of Michigan’s Huron Mountains
Michigan’s Northwoods could be destroyed by even modest climate change, researchers say:
‘Highly Invasive’ Spotted Lantern Fly Finally Lands in Michigan