By Staff
Regular readers may remember that several years ago I wrote about the plight of the Mitchell's satyr butterfly. This little chocolate brown butterfly with wings no bigger than a postage stamp is one of the country's rarest butterflies.
Once inhabiting a number of Upper Midwest and Eastern states, its last final holdout is right here in Southwestern Michigan and Northern Indiana. There are only eighteen known sites where they still exist and many of these are only a few acres in size, some less than an acre.
Like most rare species, the Mitchell's demise is habitat related. They only live in a unique wetland called a fen. Fens are like wet prairies with many of the fen's plant and grass species normally being associated with upland prairies. They are delicate places that easily lose their character with unnatural disturbance. Even a highway or drainage ditch running alongside a fen can change the hydrology enough to destroy the fen. The biggest problem with fens, though, is that they naturally grow in with invading brush. Originally fens were kept open largely by fire, both naturally occurring and those set by Indians. With fire being out of vogue for the better part of a century, many fens have simply reverted to brushy swamps. Mitchell's satyrs are very weak fliers and cannot simply pack their bags and move elsewhere. As the fen goes so, too, do the Mitchell's satyrs inhabiting it.
The Mitchell's satyr was listed as an endangered species in the 1980s. With this dubious honor comes the ultimate in protection. Sometimes that's good, sometimes not. In this case, not. This meant that without a special permit they could not be captured or even disturbed for study. Nor could the inhabited fens be managed or touched in any way shape or form. The result was that we had little clue of the habits and needs of the Mitchell's satyr. Without solid data for guidelines the Feds pretty much refused to issue study or management permits. Without the permits no data could be obtained to be used as guidelines. It was a losing catch 22 situation. Meanwhile, Mitchell's numbers kept falling as the years ticked by.
Two years ago the Feds finally realized the hopelessness of their hands off approach and began to issue some study and habitat work permits. For years I have been doing surveys where we monitored populations by counting all the Mitchell's we could find at each site. That gave me the opportunity to participate in some of these new studies. Let the learning begin! Last year I worked with a team doing oviposition studies. That's a fancy term for stumbling around in a swamp following girl butterflies until they lay their eggs. By noting where and on what they laid eggs we now have at least some insight as to critical plants in Mitchell's habitat. Last winter we also opened up some corridors between adjacent fens to see if the butterflies would move to other areas if given the opportunity. We also cleared brush from several fens that were becoming overgrown.
This year I participated in a capture, mark, recapture study. We galloped around in the marsh catching Mitchell's satyrs and numbering their wings with an ink pen for identification. The exact location of each capture was logged by GPS. As previously marked butterflies were recaptured over and over their precise movements were mapped. After nearly 2,000 captures and recaptures of several hundred Mitchell's we had very precise data on where they go and what they do, obviously very instrumental for management. My grand finale of the season was working with butterfly scientists from the Toledo Zoo to collect Mitchell's satyr eggs for captive rearing. The zoo scientists had practiced for several years rearing closely related species and were now ready for the real deal. If successful, the offspring will be released back into the wild.
The data coming from all these studies is finally giving us insight into the true life of one of this country's rarest creatures. Once sliding inexorably into the gullet of extinction, there is now a glimmer of hope. Whether we're too late or not only time will tell. Carpe diem.