September 1st   Leave a comment

Out at Fife Ness this morning there were a few waders: dunlin, ringed plover and a couple of bar-tailed godwits. I have written before about bar-tailed godwits being globally flight capable superstars and I can’t help revisiting this again after hearing a talk about them earlier in the week. The title of the talk was “There are no poor quality bar-tailed godwits in New Zealand”. I should probably add this was as part of the program of the European Ornithologists Union biennial conference (in sunny Norwich this time) where such an obscure talk title sits quite happily. Anyway, bar-tailed godwits have been studied by Jesse Conklin for the last 6 or so years and his population is the one that migrates non-stop from Alaska to New Zealand – 12 days or so flight to do 12,000 km. All the way over the Pacific from one end of the planet to the other. They have been tracked so we know that it is only the occasional bird that has to bail out and stop over on a Pacific island like Fiji. This incredible journey is the norm for these birds, not an exception. And they do it every year for 20 years or so. But the really impressive part of the journey is that the young birds do it when they are only 3 months old and they do it more or less independently, the adults having left earlier. The young feed up on the Alaskan coast after fledging – and not even the most southerly point in Alaska – and then head off for this incredible flight hoping to reach New Zealand nearly two weeks later. The navigation to do this is in itself incredible let alone the endurance. So you have probably guessed why there are no poor quality bar-tailed godwits in New Zealand. All the poor ones never make that first journey. They have to pass through the eye of a needle and any not up to scratch will simply die on the way with only a very rare second chance if they encounter one of the tiny islands scattered occasionally on the way. The population of fledglings goes through a huge selection immediately and only the fittest survive. Jesse has realised this after looking unsuccessfully for variation in the population. Normally when you study birds you find, just like people, there are individuals who are less fit than others, and so those that do better than others. But imagine if you studied the Kenyan Olympic running team: you wouldn’t really find much evidence for fitness problems, they’d just come first, second and third in any race they took part in. The New Zealand bar-tailed godwits are the elite track team of the bird world. The two out at Balcomie Beach today will not have come as far as a new Zealand bird has to, but they may have come from Taymyr in Siberia in a single flight. And when they took off in front of me as I walked on the beach they looked like every other bar-tailed godwit I have ever seen, capable of flying forever.

Bar-tailed godwit - the all time elite athlete of the bird world

Bar-tailed godwit – the all time elite athlete of the bird world

Another talk at the conference highlighted the fallibility in the incredible capability of the godwits. Such huge flights require good areas in which to fuel up. On their return journey to Alaska the New Zealand godwits take a different route. They do two flights this time, one non-stop to the Yellow Sea in China, before their final non-stop flight to Alaska. The logic of this is the godwits get to Alaska with spare energy to get breeding quickly, whereas they would need a month to recover if they flew direct from New Zealand. But the reliance on the Yellow Sea is their Achilles heel. Without this crucial link in the chain, the entire population will never reach Alaska. And the Yellow Sea is being reclaimed for industry by land hungry China at a fast rate with 30% having been lost or about to be lost already. Other wader species, such as great knot staging through South Korea, have already lost large populations as their stop-over sites have been taken away. I hope that enough habitat survives in the future for these fantastic godwits so others can wonder at their incredible journeys.

Sea-watching in the evening I saw my first sooty shearwater of the year flashing past Crail, heading round to Fife Ness and around the top of Scotland. Another global traveller passing through but linking us to the southern Atlantic rather than Siberia. My travels are over for the summer but I can watch the world coming to Crail for the next three months as the migration season really kicks in.

Sooty shearwater - I've posted this photo before but it's my all time favourite photo that John has taken - captures this exciting bird brilliantly

Sooty shearwater – I’ve posted this photo before but it’s my all time favourite photo that John has taken – captures this exciting bird brilliantly

Posted September 1, 2013 by wildcrail in Sightings

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