The Mysteries of Maine's Butterflies: The Maine Butterfly Survey
by Rebecca Reineke
When we think of butterflies, we often assign them unflattering adjectives that reduce them to fragile nonsense and children’s fantasies. Or we idolize them as beings of beauty, mirages of freedom escaping the cruel confines of gravity, ephemeral guests in our brutal terrestrial existence. Ancients even saw them as omens. But in spite of the lore, butterflies are no more or less magical than your average maladroit land mammal - your average hominid. While their appeal to our imaginations is undeniable, butterflies play a practical role in the betterment of humanity, acting as beacons on our environmental horizon.
Silver Bordered Fritterlilly (image courtesy of Rose Gobeil).
In the rural expanses of Maine, an ambitious project is under way to study the butterfly populations of the state. It is called The Maine Butterfly Survey. Dr. Herb Wilson, Professor of Biology at Colby College, is one the leaders of this formidable citizen science project as well as its main spokesperson.
“The goal is to map the abundance of twenty or so butterfly species that occur in Maine. It started in 2005 and went public in 2007. We have over three hundred volunteers who gather information for each township,” said Dr. Wilson.
Volunteers go through a training program where they learn how to document butterflies for the survey.A voucher system is used to validate finds. In order for a discovery to become an official part of the survey.
“Proof is required, in the form of a specimen or alternatively, a photograph,”said Dr. Wilson.
Bob and Rose Marie Gobeil are among the many volunteers who contribute to The Maine Butterfly Survey each season. Perennially consistent, the Gobeils have participated every year since the earliest days of the project. Their home is slightly south of Portland, Maine, about forty miles from the New Hampshire border, a location which Bob Gobeil describes as prime real estate for studying northerly butterfly migrations into the state of Maine.
“Certain southern species are moving northward in sync with global warming. We do have an advantage here close to the New Hampshire border. If any butterflies are moving northward, we will see them,” he said.
Populated areas closer to the cities have already been surveyed, leaving the vast wildernesses of Maine to be searched.
“We try to go maybe an hour away at times, trying to find sites that haven’t been surveyed. It’s a long distance to get to them. Now they want us to go further inland,” said Bob.
Gobeil notes that one of the main goals of the survey is to identify which species are more or less common and to save those habitats that appear to be deteriorating.
Red Admiral (image courtesy of Rose Gobeil).
Gobeil, a biologist, is always accompanied on the butterfly quests by his wife Rose Marie who photographs and co-documents species in the wilderness. Bob’s interest in catching butterflies began as a child and has continued to be his passion in life. Now retired, the Gobeils are as active as ever in the pursuit of their favorite insects.
“When the Maine Butterfly Survey went public in 2007, my wife and I became involved. We go out together. We are two people finding specimens,” emphasized Bob, speaking of the advantages of working as a symbiotic team.
Beginning last year, in May of 2013, the Gobeils were granted special permission to conduct a thorough two-year survey of the butterfly species on Swan Island, a wildlife management area overseen by the Maine Department of Inland Fisheries and Wildlife (MDIFW). From May through September, they scour the island for butterflies at two-week intervals. In 2013, they reported forty-two species, thirty-eight of which were vouchered, confirmed and collected by The Maine Butterfly Survey.
On June 21, 2014, at Swan Island, Bob Gobeil publicly presented their findings from the summer of 2013. In this presentation, the audience could learn about the native species and habitats unique to the island and capture butterflies for observation. One of the participants was fortunate enough to find and photograph a Bronze Copper, a rare butterfly listed as a “Species of Special Concern” by the state of Maine. That was the first island sighting of a Bronze Copper for the year 2014 and an exciting moment for everyone on the field trip.
In the Gobeil’s official report, from last summer’s survey, they list their sightings for 2013. The most common butterfly was the Inornate Ringlet at over 800 individually counted insects. Bronze Coppers, on the other hand, were seen only four times last year. But perhaps the most curious find was the insect in absentia. The Monarch Butterfly, the distinguished black and orange giant, was nowhere to be seen.
Mysterious and nomadic, one of the most compelling of all butterfly stories is that of the migrating Monarch Butterfly. Spanning the continent, the Monarch’s annual migration is epic. It defies any notion that butterflies are frail beings. Every spring, they begin their flight northward out of Mexico, spawning new generations that continue the journey. Then, according to Dr. Wilson, the last generation of the summer takes the most intense journey of all - flying southward without breeding until they arrive in Mexico, the birthplace of their great-great grandparents.
In the last twenty years, the number of Monarchs has disturbingly decreased. It is not a provincial problem. The disappearance of the Monarch is a mystery of hemispheric proportions. Clues lie all along the North American continent. According to Dr. Wilson, there are, “lots of potential hazards with migratory species.”
One of those hazards could be herbicide use in the Midwest. Monarch Butterfly caterpillars depend exclusively on Milkweed plants in order to survive to adulthood.
“We are worried about the use of pesticides that are killing milkweed plants. That might be a real threat to Monarchs. We are anxious to see what happens this year. Pesticide use is a threat to some species more than others. Unfortunately the Monarch is one species that is highly threatened in that regard,”said a concerned Dr. Wilson.
On Swan Island, the Gobeils are still looking for a Monarch.
“Right now, we have yet to see one this summer. The wintering ground was extremely small, about one and one half acres or so. With such a small population coming out of Mexico, very few will make it here,” said Bob who then added that the problem is clearly not in Maine, but further south. “We are dealing with three to four generations that migrate north. If that generation in Texas does poorly, very few Monarchs will make it to Maine. There were no great numbers in the state of Maine. I think it will be a low year again.”
The Gobeils recently published a paper in The Maine Entomologist titled Low Numbers of Monarchs (Danaus plexippus) Recorded in the U.S. and Canada During the 2013 Fall Migration. In the document, the Gobeils indicted herbicide use as well as climate change in the case of the missing Monarch.
“Climatic changes may be the most disconcerting. More frequent heat waves and droughts, especially in the Midwest, and extreme weather events such as severe rainstorms and freezing temperatures in Mexico while the Monarchs are on the wintering grounds are of special concern,” wrote Gobeil.
A Maine Monarch (image courtesy of Rose Gobeil).
Extreme temperature changes may also be perpetrating the destruction of Milkweed plants which are equally vulnerable in that way. Whichever is the main cause, it has become a struggle for the Monarch to migrate northward while maintaining its population size.
“There is a possibility that there might be a recovery, but it seems that every time there is a recovery, it is never as high as the previous recovery. It comes to a point where it will be difficult to recover. They will not be extinct soon, but they will decrease,” said Gobell.
As for Swan Island itself, the habitat is “perfect” for Monarchs with abundant Milkweed plants and otherwise ideal conditions. The Gobeil’s report also noted that the island could,“likely be one of the few State wildlife management areas in the U.S. actively managed for butterflies.” Experimental periodic mowing practices on the island and in certain Midwestern states could influence the way bird and butterfly conservation is handled in the future. This could help with repopulating certain species across the United States.
Nearing its conclusion, The Maine Butterfly Survey has one more year left. Dr. Wilson says that the next phase is to preserve the collection in a lasting form for posterity.
"2015 will be the last year of field work. Then there will be book - an atlas. It will provide a baseline for what the butterfly situation is like in Maine at the beginning of the twenty-first century. No one has ever done a comprehensive atlas of Maine butterflies before,”revealed Wilson.
When asked to give one final thought on the Maine Butterfly Survey, Dr. Wilson applauded the efforts of the volunteers, those citizen scientists who surpassed expectations by gathering an astonishing amount of information.
“We have added several species, such as the Short-tailed Swallowtail,” said Wilson, noting that it was found in Aroostook County, Maine, by Phillip and Emmet deMaynadier. “Prior to this,” he continued, “It had only been documented in New Brunswick and Nova Scotia, but never in the contiguous United States.”
Undeniably, the statewide survey is already a success as it has generated a lot of public interest in butterflies. Concerned citizens and officials will have vital statistics that may help predict the progression of local ecosystems as well as the health of the western hemisphere.
“This shows the power of citizen scientists.” concluded Dr. Wilson.