Monday, July 2, 2012

4th of July Butterfly Count

White Admiral Butterfly --only one was found during our survey
Every year during the last week of June, a couple of us locals participate in the Annual Butterfly Count. This nationwide survey (plus Canada and Mexico) is sponsored by the North American Butterfly Association. The Butterfly Count is patterned off of the National Audubon Society’s Christmas Bird Count which takes place annually in mid December. In fact the 15 mile diameter count circle that we use for the Butterfly Count is precisely the same one that we use for our local Christmas Bird Count.
15 Silver-spotted Skippers were seen on the day of the butterfly count

The objective of the Butterfly Count is to spend a day counting every butterfly that we see in an assigned area within the count circle. We note each species and number of individuals found. We also keep track of our time in the field and how many miles we cover while counting. All of the collected information will go into a database that will help conservationists understand more about the health of butterfly populations and their species' distribution throughout the continent.

2 Dun Skipper were located during the count
Unlike the bird Count, the butterfly count’s exact date is not selected far in advance. Inclusive are any dates in June or July. The Count is generally known as the 4th of July Butterfly Count since most of the leaders that run the individual counts choose a date near the July 4th holiday. Our own count has traditionally been run in the last week of June.
14 Great Spangled Fritillary were seen -most were at the nature preserve

For the day to be productive we need to pick a warm, relatively cloudless and windless day –all conditions favorable for the maximum butterfly activity. Normally the count day is selected just a few days ahead of time so that the weather forecast is more accurate. The truth is if you choose a cold rainy day, you might as well stay home, because no butterflies will be flying.

The Hickory Hairstreak  - 3 were found at the nature preserve
My counting territory is largely restricted to our nature preserve, while the count leader takes his own well-established route that samples a larger part of the good butterfly habitat in our count circle. The leader and founder of our count is Ernest Williams, a Hamilton College Professor and nationally known butterfly expert.

A Striped Hairstreak Butterfly drinks from Milkweed flowers 
On Thursday, I found 28 butterfly species at the nature preserve and a total of 223 individuals. We collectively found a total of 591 butterflies representing 32 differnt species. The most common species was the Cabbage White–a nonnative. The Cabbage White almost always attains the 1st or second most common status on our count, and I suspect on many other counts conducted throughout the country.

15 Baltimore Checkerspot Butterflies were located  -all in wet meadows

Not nearly so common, the Baltimore Checkerspot, one of my all-time favorite butterfly species, was located in our nature preserve’s boggy wetland. The wetland is populated by the plant called turtlehead, which is the Checkerspot’s main food plant. There I found only one adult, but Ernest located 15 checkerspots in a wetland a few miles to the north. This species had become hard to come by for the last several years, so we were pleased to see that they finally seem to be having a good year.

19 Monarch Butterflies were found -this male is feeding on Milkweed

In a normal year, the Milkweed Plants are just beginning to bloom during the last week of June, but this year the blooms of milkweed, as well as many other field plants, were much more advanced. This meant that there were a lot more flowers than usual to check for butterfly visitors.

Monarch Butterflies were well represented at the nature preserve this year. Most were found in meadows filled with their hostplants (Common Milkweed) and some were seen laying eggs on those plants. In early successional fields where young willow seedlings are common, the Monarch’s smaller lookalike, the Viceroy Butterfly, was found. No surprise, the Viceroy’s foodplants are trees in the willow family.
16 Questionmark Butterflies were seen during the count

Acadian Hairstreak Butterflies also lay their eggs on Willow, but this year I found none of that species anywhere at the preserve. However, during the course of the morning, I did find 3 other species of hairstreak butterfly, including the Hickory Hairstreak, Banded Hairstreak and Striped Hairstreak.

10 Eyed Brown Butterflies found in our boggy wetland

Restricted to the habitat of our boggy meadow was a decent sized population of Eyed Brown butterflies –these guys turned out to be the only representatives of their species found on our count. The caterpillars of Eyed Brown Butterflies feed on sedges, which grow plentiful in that particular wetland.

9 Red Admiral were found during our count, but I expect more to emerge any day now
The Red Admirals that were so plentiful earlier in the early spring were found only in small numbers by both of our teams in the field. I suspect the numbers of this species will be increasing any day now, as the progeny of those original migrants begin emerging from their chrysalises, which are no doubt hidden away in wooded recesses throughout the region.

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