Bar-tailed Godwit in Chatham One of a Species that Flies 7k Miles Non-stop

Jul 19, 2017

I don’t know if you’ve heard, but there’s a world champion in town, and I don’t mean that Brady and Belicheck are visiting their respective Cape and Islands summer homes. The world champion of all animal migration has made an improbable visit to the outer beaches of Cape Cod. 

And like the ornithological equivalent of paparazzi, birders from all over the region grabbed their big lenses and are swarming to catch a glimpse of this champ.

 


A suspicious large sandpiper with the characteristic super-long and slightly upturned bill of a godwit was first reported in Nauset Marsh in Eastham about a month ago, but the ID was never clinched. Last week, probably this same bird showed up on the mud flats at Mass Audubon’s Tern Island sanctuary in Chatham, where the dean of Cape Cod birding, Blair Nikula, was able to nail down the identity of this wayward shorebird: it was a Bar-tailed Godwit. Having found the majority of the rare shorebirds on Cape Cod over the last few decades, Blair knew of what he spoke. Not satisfied with just a species-level identification, he noted that the bird’s structure and under-wing color revealed it to be the Siberian breeding subspecies of Bar-tailed Godwit, rather than the Scandinavian form. This important detail placed this bird squarely in the world-champion class of migrants.

 

You see, the Bar-tailed Godwits breeding in Siberia or western Alaska have been shown via satellite tracking studies to migrate non-stop from Alaska to New Zealand each summer. This flight was suspected but not proven for many years. Then, beginning on August 29, 2007, one particular female bearing a satellite backpack, with the unassuming name E7, flew 7258 miles non-stop from the Avinof Peninsula in Western Alaska to the Piako River in New Zealand. Why no one thought to name this bird Amelia, I will never understand. With this flight, E7 set the new world record for non-stop migration by any animal without feeding. Because godwits can’t land on the water, this meant eight straight days of continuous, and foodless, flapping over the trackless Pacific. This kind of puts your cardio routine in perspective.

 

These birds get downright lazy in spring, when they fly a mere 6000 miles non-stop from New Zealand to China’s Yellow Sea. After refueling there it’s a leisurely 3,000 miles non-stop to Alaska. So how do they accomplish this seemingly impossible athletic feat? While human distance athletes stay thin and then load up on carbs just before the race, the key to real long-distance racing according to a Bar-tailed Godwit is packing on prodigious amounts of fat. And while this fattening allows them to perform these absurd physiological feats, it also makes them terrible personal trainers.

 

So none of this explains why this particular Bar-tailed Godwit ended up on Cape Cod when it was supposed to fly to New Zealand. Maybe this was just a lazy youngster avoiding that scary first fall migration, or a bird with a genetic defect in its navigational abilities, which happens in a small percentage of birds. Given that it showed up in June, it’s likely that this bird got short circuited somewhere on the northbound migration in spring before wandering to the east coast. Maybe it has something to do with the fact that China is destroying large swaths of their critical spring stopover habitat by converting formerly protected Yellow Sea mud flats to industrial parks. However and for what reason it came here, I just hope this bird remembers to cash in those frequent flyer miles, because it’s a long way from Cape Cod to New Zealand.