Snow, wind, rain, and Great Snipes

Trapping at our focal lek, in slight drizzle and knee-deep snow.

For the seventh season in a row, we are in the mountains of Jämtland to study Great Snipes. The full crew is about ten people, from three different countries. The overall aim is to learn more about the spectacular snipe migration to and from Africa.

No doubt this is the latest and coldest spring since we started working here. When we arrived in Östersund on Saturday 23 May, the birch trees still had no leaves. After travelling two hours westwards up to the mountains, we got more and more the feeling of winter. The first night, when we had planned to start trapping at the leks, there were very strong winds and snow fall. Basically full winter! Trapping was cancelled, but three small groups went out to look at the conditions. Our two of main leks were completely covered with snow, which was a real set-back for our plans. Only one birds was seen at each of these leks and absolutely no breeding activity was observed. A third lek did have some birds displaying though, which gave us some hope.

A Great Snipe displaying on a small snow-free patch.

 On the next evening there was only a thin drizzle of rain and modest winds, so we could actually trap at two distant leks. Four males were trapped on one of them. At the other we had more success, trapping seven males and five females. All females got a VHF transmitter, giving us a chance to find their nests later. Five males got GPS-loggers, a device new for this season. With the latter we hope to get very detailed spatial information, both from the breeding grounds and the migration. Maybe we will be able to find some new leks this way, because we know birds may visit different leks within a season and this would certainly be revealed by the GPS-loggers.

Six males got the new accelerometers that our CAnMove technical wizards have built, which we hope will reveal more exciting details of the spectacular long flights the birds do, including the crossing of the Sahara.

This bird has recveived a CAnMove-built combined accelerometer, pressure meter and geo-locator. If retrapped next year, it will reveal at what altitude the birds are migrating, and the exact duration of the non-stop flights (which may cover up to 7000 km in one go).

The third night we concentrated on one of our old focal leks, where the snow now had melted and rained away enough to give some bare ground for the birds to sit. About five-six males were active. Maybe it was too crowded on the few bare patches, because sometimes they even displayed on the snow. For our visiting Polish Great Snipe scientists, this was especially remarkable, because this is in sharp contrast to their leks in the rich fens and peatlands of Polish lowland. We got three of the males, and they all received a GPS-logger. The weather was still very “dull”, with a constant drizzle and a cooling wind, but the spirits of the team are high!

The GPS-loggers are attached with so called leg-loop harnesses and will record the exact positions of the bird once every hour.

When writing this, we are planning for a revisit the coming night to the first site where we put on GPS-logger, to receive the very first GPS-positions of the project! The weather forecast promises slight improvements during the night, so maybe our last night here will be another memorable one. We know there are breeding Hawk Owls and Short-eared Owls along the track, and the singing Bluethroats and Ring Ouzels will surely keep us company.

The Dutch part of the team, Raymond Klaassen and Roeland Bom, will stay another few days and hopefully be able to put on the remaining two GPS-loggers and 14 accelerometers.

Raymond Klaassen and Michal Korniluk join forces to put on GPS-loggers in the best possible way.

 /Åke Lindström

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