With its dagger-like scarlet beak, dashing black eye-stripes, and long, streaming tail feathers, the Red-billed Tropicbird is a wonder to look at. But that鈥檚 a treat typically afforded only to those who live in or visit the bird's home turf in the Caribbean and on islands in the Pacific from California to the 骋补濒谩辫补驳辞蝉.
Luckily for avian enthusiasts at the Seal Island National Wildlife Refuge in Maine, one tropicbird decided to establish his summer home on the island, and has returned every year since 2005.
鈥淚t鈥檚 odd that he keeps coming back to the same spot,鈥 says Keenan Yakola, Seal Island supervisor for , which since the 1970s has restored colonies of Atlantic Puffins and other species on breeding islands in the Gulf of Maine. 鈥淗e鈥檚 very committed to it for some reason, despite the amount of effort it probably takes him.鈥
The nearest population of Red-billed Tropicbirds and on other islands in the Carribean during the Northern Hemisphere鈥檚 winter season. So it is a notable feat that this one has made the 2,000-mile journey to Maine every year, arriving in May and leaving in August.
The mysterious traveler draws birders from all over the country. John Drury, who leads boat tours from a nearby island, says he receives about 60 visitors every year who hope to catch sight of the magnificent bird. Some have come from as far as Arizona, California, and Alaska.
Not all locals welcome the summer guest, however. Since his first visits to the region, the bird has tried to get along with the island鈥檚 Arctic and Common Terns, possibly because they share similar red bills, white bodies, and black markings. But his efforts to display his V-shaped wingspan and cackling call have always been met with hostility. 鈥淗e tries to hang out with the terns and tries to belong, but they chase him away, poop on him, and pull on his long tail feathers,鈥 Yakola says. One day in July, the chase went awry when the tropicbird flew head-on into a tree and dropped to the ground. Luckily he was not seriously injured, and after a few days of rest, he was back on his daily routine of mixing it up with the terns.
He鈥檚 not the only lone-bachelor seabird known to travel north for the summer. A Black-browed Albatross, whose breeding range is around the southern tip of South America, from the 1960s until at least 2007, exhibiting similar behavior. Just as Seal Island鈥檚 tropicbird tries to fit in with terns, this albatross attempted to court a colony of gannets, which like him are big black-and-white birds. 鈥淭hese birds are obviously in the mood to be sociable, but followed a dispersal pattern that took them away from most of the species,鈥 says Kenn Kaufman, 探花精选 magazine鈥檚 field editor. 鈥淚t鈥檚 like an astronaut going into a singles bar full of space aliens鈥
Despite the Red-billed Tropicbird鈥檚 typical December-to-March breeding season, Seal Island鈥檚 special visitor has spent some summers trying to mate with a decoy of his own species that Drury set out on the water, as well as with lobster buoys that have a bright red spindle similar to the bird鈥檚 bill. In less social moments, the tropicbird relaxes in his burrow under a rock.
Hunkering down like that is a departure from the sea-wandering behavior typical of the species outside of its nesting months, says Patrick Jodice, a wildlife biologist at Clemson University. 鈥淥bservations like this are really good opportunities for us, as scientists, to be reminded of how much we still have to learn, especially about seabirds,鈥 Jodice says. 鈥淭hey are some of the most endangered birds globally for a variety of reasons, and it鈥檚 challenging to find research on many of these species.鈥
As the rarest of the three tropicbird species, Red-billed Tropicbirds have not been studied thoroughly. In an attempt to answer some of the basic questions, Jodice started tracking the birds with geolocators in 2012 to . His data shows that the Caribbean birds typically head northeast into the mid-Atlantic when their breeding season ends. But because they spend much of their time in open waters, little else is known about the birds鈥 habits during these months.
The Seal Island staff has tried to avoid conducting any research that would disturb the tropicbird, and has mostly been learning through observations. They still don't know where the bird goes when he leaves the island in August. Observers have also never seen the bird forage, and assume that he searches for food when he flies away in the evening. Some researchers on the island have begun to study the tropicbird's fecal samples to identify what he eats, but the results won't be in for a few months.
The bird was last seen on August 16, Yakola says, but there's reason for Maine birders to be hopeful about seeing him next summer. Based on Jodice鈥檚 estimate that the species鈥 longevity is about 30 years, this traveler might have another decade to continue his strange, but apparently effective, migration patterns. 鈥淎nimals don鈥檛 do things that don鈥檛 work; every decision they make is a trade-off ensuring that they can survive as long as possible and achieve reproductive success,鈥 Jodice says. 鈥淲hatever this Red-billed Tropicbird has figured out, it's working.鈥
It may be working for other Red-billed Tropicbirds, too. More have been seen off the Atlantic coast in recent years, according to Kaufman, and as the climate continues to warm, this long-distance expansion may become even more common. 鈥淚t would be amazing, but not totally surprising, if these birds eventually started nesting on the coast of Maine,鈥 he says. 鈥淭hen we would have to rethink the name."