The first cold winds announce the approach of winter in Punta del Este. It’s time for “2TK” to take flight and leave their summer resort in Uruguay to return to northern Canada, a feat that intrigues science and moves local birdwatchers.
Identified by its green plastic ring attached to one leg with “2TK” inscribed in capital letters and a metal ring with nine digits attached to the other leg, this Ruddy Turnstone (Arenaria interpres) spent the austral summer on these rocks which line the promenade facing the Atlantic Ocean to feed on mussels in the company of oystercatchers (Haematopus) and other birds.
It is when food is scarce in winter in the arctic tundra of Canada that the turnstones migrate to the south of the American continent, 15,000 km away.
In April “2TK” is now much more “chubby” and has traded its colors in shades of gray for browns and oranges, its “nuptial” plumage with which it will return to its native lands to reproduce, explains Alvaro Pérez Tort, 48-year-old amateur photographer, member of the ornithological observatory of Punta del Este which lists the stays of “2TK” in Uruguay since 2016.
He became infatuated with “2TK” and each year waits to find him to record “as many times as possible” his presence on www.reportband.gov, the continental database of bird sightings.
“What is interesting is that behind a ringed bird there is a story, there is a city, a country or a distant place, a journey and people,” said Alvaro Pérez Tort. With his location, he says to himself “that in a certain way he is part” of this story while “helping to spread it”.
– “Put the puzzle together”
According to the Bird Banding Laboratory, which coordinates the banding of one million birds a year in North America for research and conservation purposes, 2TK is about 14 years old.
It was banded in 2012 in the US Delaware Bight on the Atlantic coast, an important stopover for many North American migratory species.
For Antonio Celis-Murillo, head of the bird banding laboratory at the Maryland-based U.S. Public Geological Survey Agency, birder counts are key to “piecing together the puzzle” of each bird’s movements.
“Our work is only crowned with success thanks to the general public, to all those people who spot a ringed bird and report it,” he told AFP.
“It’s simple information but so valuable because scientifically it tells us a lot. Especially those censuses in South America that we lack,” he says of 2TK.
These surveys make it possible to trace the behavioral patterns of each species: migration path, places and length of stay in order to then refine conservation strategies.
According to a 2019 study published in the journal Science, three billion wild birds have disappeared from North America since 1970.
– Habitat loss –
Habitat loss affecting all biodiversity “clearly shows its impacts on migratory birds”, which find it increasingly difficult to make their extraordinary journeys, says Adrian Azpiroz, a biologist and bird conservation expert who also promotes ecotourism initiatives.
And while turnstones are not as threatened as other shorebirds, their population has also declined and is now estimated at 300,000 individuals on the continent. Among them, only a few hundred or a few thousand spend the “winter” on the Uruguayan coast. Others prefer the south of Brazil, or, even further south, the Argentine coast.
Scientists also claim that long-distance migrating birds have favorite wintering grounds and show high fidelity by returning there year after year, as is the case with 2TK.
Uruguay and its many coastal lagoons make the coasts “very food-productive” for shorebirds, says Azpiroz.
This is why 2TK would have already traveled nearly 350,000 km during its life, the equivalent of nine times around the Earth, an incredible feat for a bird of just over 20 centimeters.
The sophisticated physiological and neurological mechanisms that make it possible to locate oneself with such precision after thousands of kilometers traveled in several weeks of flight are still being studied.
Uruguayan birdwatchers like to think there’s also something akin to love in 2TK’s loyalty to Punta del Este.