Aspetuck Land Trust is hosting expert Victor DeMasi for its annual butterfly hike.
Searching for butterflies will happen Saturday, July 28, at 10 a.m. at the newly opened Randall’s Farm Preserve in Easton.
Mr. DeMasi, who lives in Redding, is a curatorial affiliate at the Yale Peabody Museum of Natural History and has traveled widely, studying butterflies in Africa and South America.
The walk will begin with a viewing of some museum specimens and books. To sign up, contact David Brant, Aspetuck Land Trust director, at firstname.lastname@example.org or 203-331-1906.
One of the butterfly species Mr. DeMasi expects to find is the giant swallowtail, a behemoth making a comeback in Connecticut.
Giant swallowtails, which surpass even monarchs in size, were being regularly sighted last season in Connecticut; chances are their populations are due to explode this year. They will be hard to miss — they are jet black with yellow patches, and big.
Swallowtails, like all butterflies, hatch from eggs that feed on plants as caterpillars. After weeks of dining, the insects morph into the adults we see nectaring in our gardens.
The giants feed only on mountain ash, which is fairly common in Connecticut but wilts as soon as fall frost arrives. Wilted leaves are poor feeding for giant’s caterpillars, which starve on frost-damaged foliage.
Connecticut recently experienced warmer fall weather and later frosts, which have produced excellent feeding conditions for giant swallowtails to complete their life cycle.
The Peabody Museum at Yale has specimens of giant swallowtail butterflies collected in the 1950s by several lepidopterists. They were again sighted briefly as caterpillars feeding on mountain ash in northwest Connecticut in the mid 1980s.
The Connecticut Butterfly Atlas was a massive effort over five years to document the state’s fauna. There were 110 different species of butterflies recorded by 351 searchers. More than 8,000 butterflies were sighted but not one giant swallowtail — although everybody looked hard.
The Butterfly Atlas was completed in 1999 and is one of the best local field guides to fauna in the country. It may be purchased online from the Connecticut Department of Energy and Environmental Protection bookstore for $19.95.