Tasmanian birdwatchers who traditionally gather on the state’s mudflats at this time of year to await the return of migratory shorebirds have been staggered to discover that one of the long-distance travellers has just broken the world record for avian non-stop flight.
A bar-tailed godwit making the southward journey along the East Asian-Australasian migratory flyway has been clocked flying non-stop from Alaska to New Zealand. The bird covered around 12,000 kilometres in 11 straight days.
Each year the godwits, along with 24 other species of shorebird, make a return journey of about 29,000 kilometres between their Arctic breeding grounds and wetlands in Australia and New Zealand, where they spend the summer months.
The godwits’ amazing feats of endurance have been known since 2007 when a female tagged with a satellite tracking device flew at least 11,500 km in nine days from New Zealand to Alaska.
Now this new flight by a male, which started on September 16, puts that record in the shade.
Like the previous record holder, the latest ultra-distance godwit was originally netted near Auckland and fitted with an onboard satellite tracker. After this, it headed north to south-west Alaska, where it spent a couple of months in the Alaskan tundra.
Heading south again, the godwit flew over the Aleutian Islands in the far north Pacific and landed near where it was first netted 11 days later. His tracker clocked 12,200 km, according to scientists monitoring the flight. Sometimes, the godwit reached a speed of 89 km/h, aided by tailwinds. Although the previous record-breaking flight had taken nine days, the second, slower flight covered more ground non-stop in 11 days.
The godwits are described as having the aerodynamics of a jet fighter to make such epic journeys. They also have the ability to shrink their internal organs for the migration in order to travel light.
“They have an incredibly efficient fuel-to-energy rate,” said Jesse Conklin, who is part of the Global Flyway Network, a group of scientists studying such migrations.
The bar-tailed godwit – with long knitting-needle bill – is considered one of the most dramatic of the waders, standing about 30cm tall on spindly legs.
Godwits are regarded as the harbinger of spring in New Zealand and their return has great cultural significance. To the Maori, the bird they call the “kuaka” signals good fortune.
Although these visitors are much-heralded at the far end of their range in Tasmania and New Zealand, the godwits along with other shorebirds are under threat on their migratory route.
Vanishing habitat along the flyway, especially in South-East Asia where mudflats have been drained to make way for industry, agriculture and housing are largely blamed for a fall in numbers that has seen the biggest of the waders, the eastern curlew, decline by 90 per cent in recent years. The curlew has now been declared a critically endangered.