Spring butterflies of southern Maryland

Unseasonably cool, breezy weather greeted us on Sunday for a foray to southern Maryland looking for spring butterflies. Stephanie Mason and Dick Smith took us to two sites on the Coastal Plain. The weather checked the activity of the butterflies, but we found lots of other things to look at.

on guardOur first stop was at Calvert Cliffs State Park. The playground near the parking lot is guarded by a fierce dragon made of recycled tires.

We found a spread-wing skipper, most likely Juvenal’s Duskywing (Erynnis juvenalis), according to Dick, given the time of the year; a hairstreak, a battered Henry’s Elfin (Callophrys henrici); and an azure (Celastrina sp.).

old roadThe oaks in this sandy, acid-soil habitat are tricky to ID this time of year. Working from bark, leaves, and acorn cups, we found evidence of Chestnut Oak (Quercus prinus) as well as Swamp Chestnut Oak (Q. michauxii). The understory is well-populated with American Holly (Ilex opaca) and Mountain Laurel (Kalmia latifolia).

We watched three 4-inch-long, yellow-brown elvers (Anguilla sp.) wriggling in the current of a small, shallow brook.

There is a spring hunting season for Wild Turkey (Meleagris gallopavo) in parts of the park (which might explain why we didn’t see any). Back at the parking lot for lunch, a good half dozen of us spent 10 minutes looking for a steadily-singing Pine Warbler (Dendroica pinus) that would not budge from its concealment near the top of a pine. This has not been the first time I’ve chased a bird like this: I’m inclined to consider lack of visibility a field mark for Pine Warbler.

We moved on to the Glendening Nature Reserve of Jug Bay Wetland Sanctuary, and the butterfly action picked up a bit. Several Eastern Tailed-Blues (Everes comyntas) and American Coppers (Lycaena phlaeas) were found. And flitting about its host Juniperus virginiana, Juniper Hairstreaks (Callophrys gryneus). Whereas the elfin basks with its wings held perpendicular to the ground and the duskywings spread their wings parallel, the Juniper basks in a tree “rolled over” with both wings folded together, nearly parallel to the ground and angled to face the sun.

new growthIt’s only the new growth of a Virginia Pine (Pinus virginiana), but it’s the only close-focus image that I succeeded at for the trip.

unexpectedThis little patch of prickly pear (Opuntia sp.) was a bit of a surprise.

The big mystery for this stop was a series of burrows, ranging from 1 to 2 cm in diameter, some of them ringed with a little wall of twigs and beech scales. Ben measured one of the burrows to be 10 inches deep. The consensus is that the perfectly round holes were made by one or more species of solitary bee or wasp, but we couldn’t get more specific than that.

Update: Stephanie has suggested one of the scrub burrowing wolf spiders (Geolycosa sp.) as the maker of the holes.