Tiny birds with tiny backpacks could help save Manitoba warbler species

The birds are small, and so are their backpacks — but they could deliver a big boost of information to help save a species that's on the decline in Manitoba.

A new study published in the journal Ecology shows that the Connecticut warbler makes a huge journey from Manitoba, over water, to the Amazon each year.

"It still blows my mind," said Emily McKinnon, a research affiliate with the University of Manitoba and lead author of the paper.

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McKinnon was looking at records for boreal breeding birds in the Winnipeg area when she noticed there was a gap in Connecticut warbler sightings in the fall.

"They just weren't there in the fall. They seem to sort of go towards the East Coast and then there was this blank," she said.

McKinnon started to wonder if the bird species was missing because it actually was taking part in a long-distance non-stop migratory flight over the Atlantic Ocean. A study in 2015 confirmed for the first time that the blackpoll warbler uses a similar non-stop overwater strategy, but McKinnon said it was thought that was unique to the species.

To find an answer, researchers put little tracking tags, which weigh about 10 per cent of the weight of a quarter, on the backs of 29 birds — kind of like little backpacks.

"It's really simple. All it does is it collects sunrise and sunset times and then it records that for the whole year. And the bird has to fly all the way to South America, survive, fly all the way back to Manitoba to its breeding site. I have to go out there, find the same bird, catch the same bird and cut off the harness and take the data from its tag," she said.

"From sunrise and sunset we can estimate latitude and longitude."

For a tiny bird, which weighs less than a AA battery, it's a harrowing journey. The birds travel from their breeding grounds in Manitoba, make their way to the mid-Atlantic region of the U.S. and then depart on a 48-hour non-stop overwater flight to the Greater Antilles, a group of islands in the Caribbean Sea.

They take a quick break for a few days before once again taking to the skies for a 600 to 800-kilometre flight to the South American mainland and the Amazon basin.

"It's not like they can land on the ocean. They just have to make a decision and go," McKinnon said.

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The epic flights might inspire wonder but McKinnon said she also hopes the data brings answers as to why the species' population is rapidly declining. The Connecticut warbler's population is trending down about 3.5 per cent each year.

"It really directs our attention more for where we need to go for conservation for birds like this," she said.

Another set of backpack-wearing warblers are taking to the skies with slightly better tracking tags, McKinnon said, adding the study has changed the game when it comes to understanding warbler migration.

"I think there is a big sort of amazing factor here that these are birds that might be travelling through people's backyards right now," she said.

"It's spring migration and all of these birds are flooding back and this is the kind of stuff they are capable of."