June 7, 2017
David Angelini, Fini Just and James Gonzalez.
We postponed our original plan to visit Allen Island the previous day, when even Jake Ward, the Archangel’s captain agreed the weather was terrible. The weather on this visit could only be described as gorgeous.
Our goal was to survey bumblebee diversity. Islands often harbor an eclectic assortment of species, and last August, I’d found that Allen had a higher frequency of some species that are typically rare on the mainland, including Bombus borealis. The appropriately named Northern Amber Bumblebee is a big, fuzzy, caramel-colored bee. Last August half the bees we’d seen on Allen were B. borealis. However, they emerge relatively late in the spring, so wasn’t sure if we’d find any on this visit in early June.
Two students, Fini Just and James Gonzalez, and I started the day by driving the golf cart to the island’s center and hiking the southern coastal trail in search of flowering plants and bumble bees. We had mostly missed the bloom for red maples, a favorite of bumblebee in the early spring, but not many other plants were in bloom. The hike was beautiful. We saw an eagle, a sex-spotted green tiger beetle, and a killdeer protecting her nest of eggs. But no bumblebees.
Finally we returned to the houses at the northern end of the island. In the garden, the ancient crab apple tree was in full bloom. This had been our fall-back plan. We staked-out the tree and within a few minutes, we began to catch bees as they came to the tree. Maybe this was less satisfying than hunting them down, but letting them come to us was certainly easier! 
By the end of the day, we had logged 17 bumblebees. Most were workers of Bombus vagans, a common species on the mainland that nests in forested areas and gets an early start building colonies in the spring. We also found a queen of B. terricola, a species that was once among the most common in Maine, but it has declined dramatically in recent decades.
Of course, bumblebees sting, which makes catching them a bit of an art. Honeybees live in huge colonies, where only one queen reproduces, and all the other sterile workers live altruistically for the good of the colony. Honeybees typically only sting once, because they’re killed by harpooning their strings and venom glands into your skin. Bumblebees live in smaller colonies, and so they’re less willing to sacrifice themselves if they can avoid it. But they have smooth stingers, making them able to sting multiple times. Thankfully, no one in our group we stung on this trip. (No one’s been stung yet on this project this year!) But bumblebees advertise their painful stings with their distinctive black-yellow colors. Birds and mammals learn to avoid these patterns to avoid the pain of a sting. 
Other animals can exploit the bumblebees defenses too. We caught a bee-mimicking fly, which sported the same yellow and black colors. — Actually, we caught the same fly about three times. It was not very smart, and it just kept coming back. Or maybe we were slow to learn that it wasn’t a bee — Interestingly, it looked like this fly might be modeled after B. terricola. Despite being rare these days, B. terricola, the yellow-banded bumble bee, was once widespread across New England. If an insect evolves a color pattern that can be mistaken by predators for the warning coloration of a toxic species (something called Batesian mimicry), then it makes sense for the model to be a common one. 
While we were watching the tree for incoming bees, by chance, I noticed a bee flying low over the vegetation just over the fence. It ducked into a tuft of grass and disappeared. There was no mistaking that deep amber color though. I ran around the fence, to the tuft and gently prodded the grass with a collection vial at the ready. A tense second passed. An angry buzz. Got her! A beautiful B. borealis queen. I’m not sure why she’s ducked under the grass. It was a warm, dry space, but she hadn’t yet started building a nest, and B. borealis typically nest underground. Maybe she was shopping for real estate to start her family. We took as many pictures of her as we could and released her. That made my day.
After the ride back to Port Clyde we search the village for bees without finding any, despite several big apple trees in flower. Driving home through Spruce Head, we stopped as some honeysuckle and found a species we’d not seen on Allen, B. ternarius, another common mainland species.
Too soon yet to draw any conclusions for this year, but I’ll look forward to visiting Allen next month.