Recent
butterfly (and moth!) sightings at Fermilab
Tom Peterson
August 20, 2009
August brings
some of our larger moths, such as the "underwing moths" (genus
Catocala) and sphinx moths. The underwing moths generally
overwinter as an egg, so adults are out in late summer. Some
species may have two generations per summer. Most of our
underwing moths have a bright red-orange banded hind wing which is
normally hidden under the brown or gray front wing, like in the
thumbnail photo below. Many of these are larger than the
average moth, with 3 inch or more wingspans.
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But this week
I found an "Obscure Underwing" (yes, that's its name), which is one of
several with all black hindwings, often with a white fringe. This
had about a 3-inch wingspan.

Obscure
Underwing (Catocala obscura), Fermilab, August 17, 2009.
August 14, 2009
Gray Commas are flying, as are the Eastern Commas in the woods, and also Bronze Coppers, which are such
spectacular little Lycaenids. But we do not see the large numbers
of Giant and Tiger Swallowtails this year
that we had for the past couple of years. Viceroys
seem as abundant as usual near our wetlands, and one near the center of
the Main Ring posed for me, photo below.

Viceroy, near center of Fermilab Main Ring, July 28, 2009
July 9, 2009
It has been a relatively quiet summer so far for butterflies.
Perhaps the wet spring dampened their numbers a bit. I am seeing Monarchs and Common
Wood-nymphs now in our meadows. But some species which are
often common in early summer, such as Red
Admirals, have been nearly absent. I have found a few
nice new (for my Fermilab list) moths, such as the Tersa
Sphinx and Lettered
Sphinx. But the biggest news is that while I was off at a
conference ignoring the butterflies here, Bob Lootens not only spotted
but nicely photographed a Silvery
Checkerspot on June 27. These are common just north of here
in the West Chicago Prairie, but I had never found one (still haven't,
actually, but Bob has) on site.

Silvery Checkerspot at Fermilab on June 27 (photo by Bob Lootens)
April 21, 2009
With the warm weather last week, many butterflies were beginning to
emerge. Cabbage Whites, which
overwinter as chrysalises, are as I have said before, the "dandelion"
of butterflies, a European introduction which is out early, abundant
all season, and out late. In fact, the early Cabbage Whites are
often nectaring on dandelions in our lawns. Among the first
native butterflies to emerge from its chrysalis is the Spring Azure, which were flying last
week.
However, the first
butterflies to be seen at Fermilab are generally those which overwinter
as adults in the woods: Mourning
Cloak, Eastern Comma (winter
form), and Gray Comma.
The Mourning Cloak below was photographed on March 16 in our "Big
Woods" just north of Pine Street. My first butterfly of the year
was a glimpse of an Eastern Comma flying by in the same area on March
6. In each case, these days were among the first 60 - 65 degree
sunny days this spring. Sunny and 65 F without much wind is
generally warm enough to bring out these winter hibernators in early
March at Fermilab.

Mourning Cloak,
Fermilab, March 16, 2009