Photo by Sam Galick of silvery blue at Minisink Valley Preserve (Sussex Co). Click to enlarge.
On Saturday May 28, Sam Galick and Tom Reed made the butterfly find of the year, if not the decade. They identified and photographed a silvery blue, Glaucopsyche lygdamus, at The Nature Conservancy’s Minisink Valley Preserve in Sussex County.
This seems a new species for the state. Michael Gochfeld and Joanna Burger note in their Butterflies of New Jersey (1997) that there were no definite or even hypothetical records of the species. Art Shapiro in his Butterflies of the Delaware Valley (1966) had only a handful of records and those from Pennsylvania only.
Cech & Tudor in their Butterflies of the East Coast note that the northern race, couperi, has been expanding southward “along highway corridors, feeding on introduced cow vetch,” but as far as known at the moment, no one has ever documented the species for the state.
NABA’s Jim Springer notes, “Very exciting… I am unaware of any reports since 1997 when Butterflies of New Jersey was published.”
David Wright has confirmed the identification:
“It is subspecies couperi, which has been spreading southward out of Canada in the last two decades.
“[I have corresponded] this morning with Bob Dirig at Ithaca. Bob documented the irruption of this population with a paper in [The Journal of the Lepidopterists’ Society]
“It is following the pattern that the ringlet started nearly 20 years ago moving south out of the Catskills. Very nice find. Congrats to Sam. I would consider it the first bona-fide NJ record.”
Here’s a link to a 1991 study by Robert Dirig in JLS that I believe is the one referenced by David:
The Status of the Silvery Blue…in New York by Robert Dirig and John F. Cryan
This is an out-of-South-Jersey-area report, but it’s so cool (and found by two South Jersey birder/butterflyers) that we have to note it here. If/when more details come in, I’ll update this blog post.
June 2 Update
Jim Springer reports about an effort he and others made to re-locate the silvery blue yesterday:
“A number of butterfliers from northern/central NJ went to Minisink Preserve today, June 1, to look for Silvery Blue following up the report of a single individual from last Saturday. While we had 21 species of butterflies at the Preserve, unfortunately we didn’t find a silvery blue. We investigated both the original location in the field on the west side of Clove Road as well as an extensive area on the east side of Clove Road that is a former sand/gravel pit that is in the process of being revegetated with willows, clover, grasses, etc. We’ll put the word out for people to keep their eyes open for this butterfly on their field trips in the northern part of the state. Hopefully, the butterfly seen last Saturday is the first vanguard of what will become a regular breeder within the state. It would be great to have a new addition to our fauna instead of always seeming to be losing species.”