Pearl Crescent Butterfly Party
Location: Lake Erie Coast, Toledo-area.
August 22, 2010 1:02 pm
Hello! I went on a walk along the Lake Erie shore today, and found many interesting things. One of my favorites was this group of butterflies (which I’m fairly sure are Pearl Crescents, but I’m no expert) either feasting on something or just having a good time together. Who knows! Hope you enjoy.
Katy
Hi Katy,
We believe you have correctly identified these butterflies as Pearl Crescents, Phyciodes tharos, which is represented on BugGuide, though BugGuide does indicate that there are several other species in the genus that look quite similar. In similar looking butterflies, often actual examination of the specimen by an expert is required for conclusive identification and DNA analysis is a recent, albeit expensive new tool. Though we do not believe your specimen is a Mimic Crescent, the description of the species on BugGuide includes this information: “Mimic Crescent is a recently described species that is similar to the common and widespread Pearl Crescent (P. tharos) and the Northern Crescent (P. cocyta) of the northern US/Canada. It is dubbed “Mimic” because its appearance mimics the Northern Crescent, while the mitochondrial DNA is more similar to that of Pearl Crescent. On average, they are slightly larger and have a higher, stronger flight than typical Pearl Crescent. Probably indistinguishable from Northern Crescent in the field, though Northern Crescent is not known to occur in the range of Mimic Crescent.” It is interesting to us that you called the activity in your photograph a party, because the butterflies are puddling, and a gathering like this is frequently called a puddle party. Butterflies gather at damp places and other locations to drink in fluids. The Roger Tory Peterson Institute of Natural History website indicates: “scientists don’t fully understand the function of puddling but it does appear that there are chemical ingredients that are essential for some butterfly species before they can reproduce. Research has shown that sodium is probably one of the most important ingredients but other chemicals are important too. Although mud puddles, urine, and feces seem to be the most common attractants, even carrion may be used by male butterflies; some species are attracted to specific substances while others are more generalists. … Those butterflies that participate in this behavior are the newly emerged males; females and older males do not puddle. Apparently, only those species that patrol territories, like the sulphurs and swallowtails, are the ones that puddle. It’s interesting that what probably appears to be a straight-forward behavior is not all that clear to entomologists.” The detail of your photographs clearly shows several specimens with their proboscises uncoiled and “drinking”.
