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Back in 2022, a bar-tailed godwit named B6 set a new world record for the longest non-stop migration by flying an impressive 13,558.7 kilometers (8,425 miles) from Alaska to Tasmania, Australia, at just 4 months old.
The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.To better understand the migration of juvenile bar-tailed godwits (Limosa lapponica), a study fitted the birds with tiny 5-gram solar-powered satellite transmitters, and individually coded metal bands and leg flags so that each bird could be identified as they made their first ever southern migration.
"The package has to be so small given this bird travels 12,000 kilometres. It can't have any impact on the migration or welfare of the birds," Dr Eric Woehler of Birdlife Tasmania told the BBC at the time.
After feeding on the Kuskokwim Delta near Nome, Alaska, B6 set off on October 13, 2022, and just 11 days later the bird arrived in Australia on October 26 after covering the distance of over 13,500 kilometers. These birds migrate these long distances every year, but the specific migration of juvenile chicks southbound had never before been tracked.
Bar-tailed godwits are small wading birds with a wingspan of around 70-80 centimeters (27-31 inches), weighing around 230-450 grams (0.5-1 pounds). Impressively, they are able to shrink the size of their internal organs to make extra room for fat supplies.
As a wading migrating species, their feeding sites are of crucial importance to ensure they have enough energy reserves to make their long journeys.
"We used to think they stopped on route," Sean Dooley of BirdLife Australia told IFLScience in 2022. But as it turns out, the landmasses they fly over on their epic journey "are generally not good feeding places for these birds," Dooley confirmed.
They feed on insects, worms, mollusks, and crustaceans. Alaska provides an abundance of coastal ecosystems that supply not just the godwits with food, but support a total of 37 migratory shorebird species.
The US Geological Survey (USGS) Alaska Science Center aims to identify key migration and breeding sites as well as exploring the reasons for declines in shorebird populations. The information acquired from investigations like the bar-tailed godwit study can help inform scientists and other groups of the threats that these species face.
These shore species are especially vulnerable to climate change effects like sea-level rises and habitat degradation. Further threats include habitat modification and the spread of infectious diseases.
