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07-14-05
Butterflies on Endangered Species List
The Endangered Species Program is part of the U.S. Fish and Wildlife Service. An aspect of the program is to maintain a list of plants and animals that are threatened or endangered. This is appropriately called the List of Threatened and Endangered Species. This list includes all kinds of living things.
The living things on the list are there because their population numbers are dwindling. Populations of living things decline for a variety of reasons, but one of the most common is habitat destruction. So the Fish and Wildlife Service supports work to preserve or reconstruct habitats essential to the success of the target species.
This is where the list sometimes becomes a point of contention. Some industrial and financial interests demand use of natural resources that result in destruction of habitat. Housing developments are a good example of such activity. If a threatened species lives in that habitat, a potential conflict exists. To build or not to build then becomes the question.
All kinds of animals are included on the endangered species list. There are birds, snakes, snails, fish, rodents, plants and insects on that list. Some might be surprised that insects and snails have managed to wiggle onto the list. It is easy to understand that a majestic bird, such as the bald eagle, would be included. The symbolic bird for the United States is certainly worthy of preservation. But why worry about some tiny little insect?
As it turns out, some invertebrates, including insects, are excellent indicators of environmental health. Endangered or threatened insects include beetles, flies, moths and butterflies. Butterflies are the most common of the insects on the list. For instance, the California threatened or endangered species list includes 178 plants and 111 animals, of which 18 are insects. Those 18 include three beetles, a fly, a moth and 13 butterflies. Indiana has 25 threatened or endangered species: three plants and 22 animals. The animals include two insects. These insects, the Karner blue and Mitchell's satyr, are both butterflies.
Some butterfly species are very restricted in food and habitat so it follows that changing land use patterns will affect their populations. The most recent threatened and endangered species list added five new species, including the Miami blue butterfly that, as its name suggests, is found in southern Florida.
So, on a recent trip to Iowa, I was not surprised to read in The Des Moines Register that there was going to be a search for a tiny butterfly in Poweshiek County. It was an organized effort to find the Poweshiek skipperling. The butterfly was described in 1870 and named for the country where it was collected. According to writer Kate Slusark, "The one place you'd expect to find the elusive Poweshiek skipperling is in Poweshiek County, where it was discovered 135 years ago. But experts say the tiny butterfly has been missing from its namesake county for decades."
I decided to join the hunt for the elusive Poweshiek skipperling-a butterfly that the Nature Conservancy says is imperiled globally. It is not on the national endangered species list but is listed on the Iowa Department of Natural Resources threatened species list.
I went to Arbor Lake in Grinnell to join the search for the tiny skipperling, which in the past has thrived in native prairie habitats of the area. When I arrived at the lake, I encountered some heavy equipment operators who rather bemusedly assured me that they had seen neither skipperlings nor anyone who appeared to be searching for the long-lost butterfly. I next encountered a gentleman who was picking wild raspberries. He hadn't encountered any butterfly chasers either, but he insisted that picking raspberries was more fulfilling than looking for a butterfly that probably didn't exist in the area at the present time.
I did find a car in a parking lot that had books-designed to help identify butterflies-strewn across the back. Equipment no doubt belonging to someone intent on discovering the small brown-and-orange butterfly. I searched for an hour and encountered neither butterfly enthusiasts nor skipperlings. I did see a flock of Canadian geese, which are definitely not endangered species, on the lake. All of which just goes to show that as things change, some things fit in and others don't!
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