2016-06-16

Ånn revisited



For the eighth year in a row we spent some hectic days in late May in the beautiful mountains around Storulvån in Jämtland, Sweden (63°N). With our international team, this year with people from Sweden, the Netherlands, Poland and Germany, we try to learn more about the life and secrets of the Great Snipe (“dubbelbeckasin”). Our focus is on their spectacular migrations, but since all of our field work is carried out on the breeding grounds, we cannot help getting fascinated by their breeding biology as well!


Our main hope this year was to get back one or more of the GPS loggers we attached last year. After visiting the focal leks, and realizing we got nothing, our disappointment was deep. But also short. Great Snipes are so exciting and we just need to find new ways of studying them. And the project will go on for some many years, we hope!

 
We also attached 20 accelerometers last year, and we got seven of them back. This is the expected frequency of returns (about 30%). The bad side is that none of them had worked properly, but we knew this already, so instead we saw the positive side of it – these devices certainly do not affect the birds negatively. We put on 20 new accelerometers this year, and hope for better success with them.


Weather was, for the first time in many years, on our side and we could visit, and trap at, eight leks. The first three days we visited our five “nearby” focal leks and had some good catches, and a few surprises. For example, of the only four males trapped at Lill-Getryggen, none was present last year but three were trapped the year before at Getryggen, some 5 km away! And at that lek, which was present on exactly the same spot as in previous years, only one out of nine males were ringed. That male had indeed been ringed at Getryggen three years earlier, but wasn’t trapped since then. So, of the nine males we trapped at Getryggen, none was the same as the 12 males trapped on this lek the year before! 

An especially magical night we had when we walked the almost three hours to the Tjallingen lek. We enjoyed a mild night with clear skies, beautiful scenery and a spectacular lek. There were about 30 males displaying, and we could trap 29 males and 6 females, 9 of them controls from last year. In addition we were accompanied by Long-tailed Skuas, Golden Plovers and many other mountain 
birds.


The last nights we visited three “new” leks, about 15-20 km away from our main study area, leks that didn’t get much attention before. At one we had trapped birds in our first year in 2009, and at the other two we had never trapped. In total 52 birds were trapped and not a single bird carried a ring. Given our intense ringing efforts around Storulvån in previous years, and the fact that many birds are known to switch leks, this strongly suggests that the distances the birds are prepared to move between leks are not that great.


Overall we ringed 103 Great Snipes and controlled 18 birds from previous years. Plans are already being made for next year, applications are being written and we have definitely started to long for late May 2017!

 //Åke Lindström
Photo: Johan Bäckman

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