Greenland White-fronted Geese make a 600-mile round trip each year to overwinter in Scotland but not every bird finds it easy, according to new research from Wildfowl and Wetlands Trust (WWT).
Specially designed bird ‘fitness trackers’ have revealed what happens to the birds as they struggle over the sea for long distances, trying to navigate the angry North Atlantic and getting blown off course by unpredictable storms.
Migration is a particularly vulnerable time for Greenland White-fronts. One goose took just 14 and a half hours to fly from Iceland to Greenland, but two others took days to complete the same journey, being forced to spend a lot of the time bobbing on the sea.
WWT researcher Ed Burrell has just returned from the tiny island of Islay, Argyll, where he’s been downloading data from the bird fitness trackers. He said: “We’ve just downloaded all this amazing data from these individual birds to see what they’ve been up to. From studying the leg from Iceland to Greenland in May this year, we see what a difference a day makes.
“We can tell that the weather turned on two birds who left the same evening, as they landed on the sea – so they wouldn’t be blown further, of course. By using an extra gadget called an accelerometer – a bird 'fitness tracker' so to speak – which measures the movement of the tag, we can tell that they bobbed about for a bit. To avoid the terrible conditions, the birds went for a swim.”
The blue-tagged goose left Iceland at 3.30 am on 6 May in calm conditions, arriving in Greenland 14-and-a-half hours later at a speed of 33.5 mph. The green-tagged goose left at 4 pm on 3 May accompanied by a good tailwind that later turned on the bird, blowing it towards the Arctic Ocean and forcing it to hunker down in the sea. It later landed in Greenland 53 hours after its journey began.
The red-tagged goose had it even worse, leaving the same evening as Green, but taking a traumatic 63 hours to complete the trip.