If you’d like to know more about butterflies and help in their conservation, consider joining the North American Butterfly Association’s Rappahannock Butterfly Count, coordinated by Old Rag Master Naturalists, on July 27. No butterfly expertise is required.
Volunteers will get a brief training session and handouts to help with butterfly identification, and each team of counters will be led by an ID expert. For more information or to register for the count, visit oldragmasternaturalists.org (click on “Official 2013 NABA Butterfly Count in Rappahannock” on the left) or contact Don Hearl at 540-825-6660 during the day, after 5:30 pm at 540-672-5712 or by email at firstname.lastname@example.org.
This time of year, butterflies seem to be everywhere. While we expect them to be drifting over meadows and through forests, sometimes they appear in what may seem like odd places, such as around mud puddles. This week I decided to dig deeper into that phenomenon and also explore a new database for learning more about rare butterflies and other insects.
This spring, with all the rain we’ve had, clouds of butterflies, particularly swallowtails, were everywhere along our back roads, swarming around mud puddles. Among butterfly enthusiasts, this activity is known as “mud-puddling,” or simply “puddling.”
While I’ve long been familiar with the phenomenon, I was never clear about what the butterflies were after beyond vague explanations, such as “nutrients.” Digging a bit deeper recently, I found an article by researchers Jan Beck, Eva Muehlenberg and Konrad Fiedler, published in the journal “Oecologia” in 1999, that offered some answers. The article was aptly titled “Mud-puddling Behavior in Tropical Butterflies: In Search of Proteins or Minerals?”
Noting that adult butterflies and moths of many species “frequently visit moist ground, perspiration, tears, excrements or animal carcasses to suck water and dissolved nutrients,” the researchers used various lures of salt and amino acid solutions to find out just what those nutrients are. They determined that “overall, albumin solutions turned out to be the most attractive puddling resource.” Albumin, which is rich in protein and nitrogen, is found in blood plasma and egg whites.
Although albumin was on the top of the attractant list, the researchers also found that “butterfly families differed consistently in their resource preferences.” While the families of Lycaenidae (gossamer-winged butterflies – hairstreaks, coppers, harvesters and blues), Nymphalidae (brush-footed butterflies – longwings and fritillaries, crescents and checkerspots, brushfoots, and satyrs) and Hesperiidae (skippers) preferred the protein resource, salt solutions were more likely to attract Papilionidae (swallowtails) and Pieridae, a large family that includes whites and sulphurs (mostly smallish butterflies that are yellow, orange or white).
So how do the butterflies find these nutrients? The researchers found that visual cues, such as color, play an important role in locating puddling resources for butterflies in the Papilionidae and Pieridae families, which were looking for salt, while butterflies in the Lycaenidae family relied more on olfactory clues emitted by decaying organic matter to find nitrogen sources.
Interestingly, the researchers also found that “with one single exception, all attracted butterflies were males.” The explanation? “The strong attraction of male butterflies to nitrogen-rich resources suggests that, as in the case of sodium, these nutrients may increase reproductive success.”
Most of us who like to observe animals hope in the back of our minds that someday we’ll spot a rare one. Sorting out the common from the rare among some insects is now easier, thanks to an online resource the Virginia Department of Conservation & Recreation’s Division of Natural Heritage launched last year, the Atlas of Rare Butterflies, Skippers, Moths, Dragonflies & Damselflies of Virginia, at vararespecies.org.
The database was developed with funds provided by the Virginia Department of Game and Inland Fisheries through a state wildlife grant from the U.S. Fish and Wildlife Service and contains information on 193 species that are rare to Virginia; many are also rare nationally and globally.
The atlas has fact sheets for each species that include information about the species’ ecology and life history, identifying characteristics, photographs, population trends and potential threats, a county-level distribution map, images and more.
Database users can search on a species’ scientific or common name to get a summary of its state and national conservation-status ranks and a list of counties where the species has been observed in Virginia. Searches can also be done by the name of a locality to get a list of the rare species observed there.
I pulled up the county list for Rappahannock and found four butterflies – frosted elfin (Callophrys irus), early hairstreak (Erora laeta), atlantis fritillary (Speyeria atlantis) and regal fritillary (Speyeria idalia) – and one damselfly, the Appalachian jewelwing (Pyrgus centaureae) on it. The jewelwing is also on the Culpeper list, along with a dragonfly, the rapids clubtail (Gomphus quadricolor).
According to the DCR press release, zoologists used a variety of resources to develop the atlas: the latest survey data, published literature and reports, field notes from biologists, museum specimens and the personal records of knowledgeable naturalists, collectors and scientists.
The database is not only important for butterfly enthusiasts who want to know more about rare species in the Old Dominion; it will also help in setting priorities in conserving Lepidoptera, some of which depend on a single plant for their survival.