GRAND RAPIDS, Mich. (Michigan News Source) – The John Ball Zoo is working to save endangered species of butterflies.

The zoo says it has been working to restore the population of the Mitchell’s Satyr butterfly, which is a small brown butterfly that is federally endangered. In addition, zoo staff has been raising the Poweshiek skipperling which is also endangered.

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Between the two endangered species, the zoo says it has released more than 450 butterflies back into the wild so far this year. They expect more to be released over the coming months.