When learning about the immense migrations of many North American birds, the more zoomorphic among us may find themselves imagining what wondrous things these birds must encounter throughout their travels. From high Andean cloud forests to tropical Central American beaches to stark Alaskan tundras, these birds see a lot. Which may in turn lead us to wonder: what bird has the biggest lifelist?
First, how can we measure such a thing? Obviously, length of migration is an essential factor. Yet the arctic tern has the longest migration of any bird, and no doubt sees more of this world in its lifetime than even the most intrepid among us could hope to, but in terms of pure list-building, the arctic tern probably has a fairly modest list considering it avoids tropical forests brimming with species. No doubt a superciliaried hemispingus living in Manu National Park, the world’s epicenter of avian diversity, could trounce even the most observant arctic tern’s lifelist.
Perhaps more important than length of migration is diversity of habitats visited during migration and diversity of species within each of those habitats. Longevity is another important consideration. We can bet on the fact that Wisdom has picked up a vagrant or two in her many years of globetrotting. With those criteria in mind, here are some birds that could go toe-to-toe with even the most well-traveled listers.
1) Barn Swallow
The North American subspecies, erythrogaster, winters as far down as central Chile and establishes breeding territory into Canada. What’s notable about the barn swallow is that a sizeable percentage of the population migrates overland through Central America, moving through one endemic region after another. Any barn swallow hopscotching the Caribbean should meet with a fair share of lifebirds too.
2) White-rumped Sandpiper
Many shorebirds are justly famous for their yearly peregrinations, but one of the biggest shorebird big listers has got to be the white-rumped sandpiper. Breeding in Alaskan and Canadian tundra, most birds migrate through the Heartland or the East Coast before crossing the Caribbean and landing in northern South America. Once on the southern continent’s mainland, they move southeast along the coast before heading inland over the Amazon Basin. Finally, they reach their wintering grounds in southern Argentina, even as far down as Tierra del Fuego. White-rumps are famous for conducting their migrations in massive chunks, so it’s possible they wouldn’t build up their lists as impressively as one might imagine for a bird that travels so broadly, but any individual white-rump with the gift of longevity would surely be in contention.
3) Blackpoll Warbler
The longest migrant of any of the wood-warblers, the blackpoll warbler starts its year in various forest habitats of northern South America and sometimes as far south as northern Bolivia. In Spring migration, blackpolls move across the Greater Antilles, bagging Caribbean endemics and pelagics along the way, before dispersing through the Midwest and eastern US to finally breed in Canada and Alaska. In Fall migration, blackpolls take a more eastern route, departing the North American mainland from the East Coast and flying across the Atlantic ocean, then passing through the Lesser Antilles before finally reaching Venezuela and other northern parts of the bird continent, where they disperse. With that kind of habitat coverage, do blackpoll warblers regularly break 1000 birds a year? If only we could ask.
4) Swainson’s Thrush
Breeding nearly as far north as the blackpoll warbler and ranging significantly further south, as far away as northern Argentina, the Swainson’s thrush is in the hunt. Being a mostly nocturnal migrant, any Swainson’s familiar with the flight calls of other nocturnal migrants might fare particularly well. The gentle serenader of your local patch surely comes up with a yearlist the rest of us could drool over.
Possibly the most competitive raptor is the osprey, which breeds in Alaska and Canada before migrating south throughout the US, crossing the Caribbean, and arriving in Central America. Some winter as far down as northern South America. Considering ospreys move so broadly and cover both coastal and non-coastal habitat, they’re surely in the running for top lister. Note that some ospreys in Florida and California aren’t that big into listing and are non-migratory.
6) Arctic Warbler
The only Old World warbler to establish a foothold in North America is the arctic warbler, now belonging to the leaf-warbler family Phylloscopidae but formerly a part of the once massive Sylviidae. The kennicotti subspecies winters in the species rich Philippines and migrates up through various Asian islands and Russia to breed in the western Alaskan mainland, covering more than enough ground to be a competitive lister.
7) Northern Wheatear
Let’s not forget the passerine with the longest migration. Two subspecies occur in North America, and both have massive migrations. Some members of Oenanthe , the nominate race, breed in western Canada and Alaska after migrating from sub-Saharan Africa across the Arabian desert, Siberia, and the Bering Sea. Leucorhoa winters in western Africa, and then passes through Europe and the British Isles to breed in Iceland, Greenland, and as far west as eastern Canada. Occasionally, members of that race wander south to New England, fortifying their lifelists all the way.
8) Chimney Swift
Any bird that winters in the Upper Amazon Basin can be a contender for the biggest bird listing bird. A concern with chimney swifts is that they spend too much time gliding high above to tick some of the real skulkers of the Neotropics, but at least they’ve got a good vantage point for the canopy dwellers.
9) Scarlet Tanager
Not many tanagers are long-distance migrants, but the scarlet tanager is enough of a wayfarer to hold its own against the shorebirds and wood-warbler wanderers of the world. Ranging as far south as Amazonia and the lower regions of the Andes, the scarlet tanager migrates across the Gulf and breeds in Midwestern and eastern forests as far north as southern Canada. Those are some pretty species rich lifezones.
10) Red-eyed Vireo
The red-eyed vireo ranges as far south as Bolivia, Paraguay, and Argentina, and breeds as far north as Canada, but what really sets this species apart is that some individuals that winter in the very southern tip of their range migrate only as far north as Central America, passing through forested areas the entire time. So we’re talking about birds that spend their whole lives moving from one Neotropical forest to another. That’s a lot of lifers.
Note that Old World birds, due to the author’s ignorance, were mostly not considered for this article. But the piece is as much a crowdsourcing effort as anything, so please contribute your best guesses in the comments.
The prospect of vagrant individuals makes the thought-experiment even more intriguing. How about a pectoral sandpiper in Australia, ticking Eurasian peeps and other shorebirds in rapid succession? Indeed, when considering which bird has the biggest lifelist, one can’t help wonder whether the very question might help explain the phenomenon of vagrants and accidentals.