A Stellar’s sea eagle, native to East Asia. Design Pics Inc./Alamy

These two themes, birds and their various forms of adaptation, make Marion Renault’s article These Birds Aren’t Lost. They’re Adapting a perfect fit for sharing here as an excerpt, and recommending that you read the story where it was published:

Bird-watchers love to see vagrants, or birds that have traveled far outside their range. But scientists say they have a lot to teach us in a world facing ecological change.

From what we can tell, the Steller’s sea eagle trekking across North America does not appear homesick.

The bird has strayed thousands of miles from its native range in East Asia over the last two years, roving from the Denali Highway in Alaska down to a potential sighting South Texas before moving eastward and back north to Canada and New England. Its cartoonish yellow beak and distinctive wing coloration recently attracted crowds of rapt birders to Maine before turning up on April Fools’ Day in Nova Scotia.

“We live in a world of very little surprise,” said Nick Lund, the outreach manager for Maine Audubon and creator of The Birdist blog. Catching a glimpse of a far-flung bird in one’s backyard, he said, “is like the purest form of joy.”

But the rogue Steller’s sea eagle isn’t just a lost bird: It is an avian vagrant, a term that describes birds that wing their way well beyond their species’s normal range of movement.

Humans have long marveled at such exotic stragglers — which experts also refer to as waifs, rarities, extralimitals, casuals and accidentals — and what they suggest about the biological importance of wandering. “The ‘accidentals’ are the exceptional individuals that go farthest away from the metropolis of the species; they do not belong to the ordinary mob,” Joseph Grinnell, a field biologist in California, noted in 1922. “They constitute sort of sensitive tentacles, by which the species keeps aware of the possibilities of aerial expansion.”

The peripatetic sea eagle wasn’t 2021’s only extralimital. Other fan favorites strayed from the parts of Central and South America where they are typically found: an Inca tern spotted in Hawaii; a small-billed elaenia captured in a net in Quebec; a heron-like limpkin recorded in Texas for the first time; and, a gray-breasted Martin observed in Prospect Park in Brooklyn.

“Each time there’s a vagrant it’s its own exciting story,” Mr. Lund said. “It has this treasure hunter’s charm.”…

Read the whole review here.