The Bar-tailed Godwit (Limosa lapponica) has one of the longest (if not the longest) flight paths of any migratory bird on the planet. Few, if any species, can match it. Let's begin with a look at its life history.
There are two subspecies of the Bar-tailed Godwit, the Asian and the European. The European subspecies breed in eastern Europe and Iceland and spend their winters in Mauretania and western Europe. The Asian subspecies breed on the western slopes of Alaska and winter in New Zealand. Either subspecies is a rare visitor to North America. A few can be found in Alaska and the Pacific coast. Rarely one might be found along the Atlantic coast. They nest in shrubs, sedge clumps and bogs on tundra and taiga.
The Bar-tailed Godwit is about the same size as the other godwit species. It measures 33-42 cm (16 in). Its distinguishing features are: relatively short legs (compared to the other godwits), white or barred underwing coverts, and a white or barred rump. In breeding plumage the male shows a rufous colour all the way to and including the tail underparts. The Asian subspecies shows the barring on the underwing and rump, but the European subspecies shows plain white. Note, the Black-tailed Godwit shows heavy barring in the belly and undertail parts.
Now let's consider the world record migration path of this species. The following material is taken from a recent publication of Birdwatch Canada, Winter 2021, Number 94, p. 19, in an article written by Jody Allair and Pete Davidson. The incredible features about the migration of this species is the distance it flies and the time it is in the air, non-stop without touching down to feed and rest. The ability to place satellite transmitters on large birds has given us these amazing facts. Migration studies are blessed with modern technology.
The studies have found that in the fall, the Bar-tailed Godwits leave Alaska and fly non-stop to New Zealand. That is a trip of more than 11,000 km and they take 8 to 11 days to do it! Yes, that is correct. They fly non-stop over ocean for 8 to 11 days and cover over 11,000 km. That is astounding. That is a fact we moderns can now marvel at. I wonder if Roger Tory Peterson would have believed it. These same birds who flew so far to go to wintering grounds return in the spring by a different route. They fly 8,000 km from New Zealand to the Yellow Sea in China and to the Korean Peninsula. There they stop to rest and refuel before they continue on the rest of their journey, 6,000 to 7,000 km to Alaska. Wow, take a look at a globe/map and appreciate how large the Pacific Ocean really is.
In this study the bird that flew the farthest was a male who flew 12,200 km non-stop in 11 days. This breaks a previous world record set in 2007 also by a Bar-tailed Godwit. This truly is awe-inspiring!
If you are paying attention, there is at least one weak link in the chain of these migratory flight paths. Did you catch it? Yes, the Yellow Sea in China and the Korean Peninsula. As you know there are huge human populations there with all its activity, pollution, coastal garbage, etc. The loss of the intertidal flats there would (and have) cause a severe decline in the Bar-tailed Godwit population.
This study was a collaboration between Bird Studies Canada, Birds New Zealand, Massey University, and the Global Flyway Network. Please consider supporting these groups so they can continue their studies and attempts to protect our migrating shorebirds (and others).
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