GWC Prior Butterfly Stories 2003 continued ( Page 8 )

Butterfly species numbers are starting to rise to respectable levels in southeast Michigan. On Saturday April 26, I surveyed Crosswinds Marsh in southwest Wayne County and found seven species. Among them were my first American Painted Lady (Vanessa virginiensis) and my first two Sleepy Duskywings (Erynnis brizo).

The next day Sunday April 27, I surveyed the Nature Conservancy's Nan Weston Preserve and neighboring state game lands in southwest Washtenaw County. The species total increased to eight for the day. Among them was my first Tiger Swallowtail (Papilio glaucus). It was floating and landing on the floor of the Beech-Maple forest at Nan Weston. The very smallness of the butterfly made quite an impression. Another good find for the day was a lone Gray Comma (Polygonia progne) on state game lands off of Prospect Hill Road.

This site also produced disappointment since no duskywings or Pine Elfins (Incisalia niphon) were flying at the White Pine-dry prairie location there. During the past four years, Pine Elfins have been consistently found here. Hopefully they are still there and will eclose sometime this week.

On Monday April 28, I visited the Geology Center area in northwest Washtenaw County and had a total of 10 species for the day. The best finds were Brown Elfins (Incisalia augustinus) at Cedar Lake bog and a second Blueberry bog north off of Bush Road. At both locations the Brown Elfins seemed most interested in the Leatherleaf (Chamaedaphne calyculata) and it would not surprise me if they are using it as their host plant. Other good butterfly species Monday included two more Tiger Swallowtails, a Sleepy Duskywing, and three American Painted Ladies. One of the American Painted Ladies was visiting Pussy-toes that were just coming into bloom and spending a lot of time at the plants--a possible indication of oviposition.

Again on Monday there was more disappointment in not finding Pine Elfin, this time at Cedar Lake. The campground area at Cedar Lake has several nice patches of White Pine and has been over the years the traditional location to find the Pine Elfin in Washtenaw County. However getting the timing just right to see Pine Elfins there always seems to be tricky. First the species never seems to stay out and be visible for an extended period of time. More trouble arises from the fact that either the campground maintenance people mow down all good nectar sources (Pussy-toes and Wild Strawberry) for the butterfly at the site or squads of hungry dragonflies overrun the area. On top of all this, the breeding population there does not seem large--I have never seen more than 10 Pine Elfins at any one time. The butterfly could well be at risk for a local extinction. That would be a tremendous shame since it is such a beautiful species.

April 26-28 Butterflying Summary:
======================================================================
Crosswind Marsh          Sharon Valley Area        Geology Center Area
---------------          ------------------        -------------------
Mourning Cloak           Spring Azure              Spring Azure
Cabbage White            Mustard White             Eastern Comma
Red Admiral              Eastern Comma             Mustard White
Sleepy Duskywing         Mourning Cloak            Brown Elfin
Spring Azure             Tiger Swallowtail         American Painted Lady
American Painted Lady    Red Admiral               Mourning Cloak
Eastern Comma            Cabbage White             Cabbage White
                         Gray Comma                Red Admiral
                                                   Sleepy Duskywing
                                                   Tiger Swallowtail
=======================================================================

My trip to Petersburg State Game Area on May 28 was quite successful. For the day I found 26 or 27 species. The most important of them was a Dusted Skipper(Atrytonopsis hianna). This butterfly, which was vouchered for the Michigan Lepidoptera Survey, represents only the second sighting of the species in the history of the Greater Washtenaw County Butterfly Survey and the first since 1996. I discovered the butterfly while I was checking the Wild Lupine for small duskywings. Out of the corner of my eye, I saw this small black skipper zipping around the fields and I immediately thought I found a Roadside Skipper (a very good butterfly at Petersburg also latter seen that same day) so I went over to check it out. As it landed, I could see that it had white apical spots. So I knew I had to catch it as it was probably a Dusted Skipper which was confirmed once captured.

Other good butterflies found at Petersburg on May 28 included Dreamy Duskywing (Erynnis icelus), Sleepy Duskywing (Erynnis brizo), Common Sootywing (Pholisora catullus), Roadside Skipper (Amblyscirtes vialis), Purplish Copper (Lycaena helloides) and Northern and Southern Cloudywings (Thorybes pylades and bathyllus). The Roadside Skipper was the first seen at Petersburg since 1998.

An interesting fact about the Purplish Copper sightings (5 butterflies) was that all of them were in the dry prairie area where Sheep Sorrel and American Coppers are dominant. Could it be that Purplish Copper is now naturalizing on Sheep Sorrel a Rumex as a larval host plant? It would be great if it was since Purplish Copper is a decidedly uncommon and localized species in Southeast Michigan when dependent on native hostplants. I have since noticed similar behavior by Purplish Copper in two other dry sites in southeast Michigan ( Sharon Valley Road SW Washtenaw county), so I will be making a special effort to see and document if any of female Purplish Coppers oviposit on Sheep Sorrel.