The Karner Blue – a small, powder-blue butterfly – once lived in oak savannas and pine forests in the Midwest and Northeast.
But over time, much of the Karner Blue’s habitat has been destroyed, and today only a few small populations remain in areas such as Michigan, Wisconsin and New York.
Now climate change poses a whole new threat to this endangered butterfly.
The caterpillars of the Karner Blue butterfly feed exclusively on a plant called wild lupine. However, as winters have become warmer, the caterpillars hatch earlier in the year, before the lupine emerges from the ground.
Hoving: “And then there is nothing left for them to eat and they cannot survive.”
Christopher Hoving works for the Michigan Department of Natural Resources.
He says that a similar timing discrepancy could occur in the fall.
Normally two generations of Karner Blues hatch each year, but higher temperatures may cause a third generation of eggs to hatch instead of remaining dormant over the winter.
These Karner Blue caterpillars may have trouble growing and laying their own eggs before it gets too cold. And they may have trouble finding food.
Hoving: “In autumn there are actually no lupin plants in the landscape. … That is one of the biggest threats.”
Climate change could bring these lively little butterflies even closer to the brink of extinction.
Reporting credit: Ethan Freedman / ChavoBart Digital Media
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