Common Ringed Plovers from south to north (2:2)

The field station with the lake Latnjajaure in the background, still covered with ice and snow.
Loading up a helicopter with three weeks worth of supply and field equipment is always exiting. Loading one that it’s heading to a place where data loggers sitting on Common Ringed Plovers is even more exiting. Except for my self three other people were preparing for getting up to Latnjajaure (jaure means lake in Sami) in Abisko, working with everything from plant phenology to gas emissions in post-permafrost sites. With the mountains in our bearing we took off from the helipad in Abisko on the 14th of June.

A newly ringed Common Ringed Plover with an activity logger visible on the back.

The reason for my stay was to catch Common Ringed Plovers. As mentioned above to retrieve geolocators, but also deploy new ones. In an earlier blog post from June 13th I mentioned that this year I use activity loggers. This gives the opportunity to in better detail describe a number of aspects of flight performance in the Common Ringed Plover, such as duration of individual flight bouts and the number of flights and consecutive stop-overs. The overall aim is to compare these aspects between populations migrating different distances and breeding/wintering in different climate zones. The population this field trip is aimed for breeds close to one of the Abisko Scientific Research Stations/Swedish Polar Research Secretariat’s field station in Latnjavaggi (vaggí means valley) approximately 15 km west of Abisko. 

A Common Ringed Plover nest beautifully placed among flowering Alpine Azela (krypljung) and Dwarf Willow (dvärgvide).
Despite the present warm weather down in Abisko there was as usually much snow left up around the lake. This year was particularly late and much of the previous breeding sites were covered with snow. During the first days I was somewhat worried that the plovers had given up the site already in the beginning of June, when they usually arrive. The only two individuals observed during the first two days were one unmarked (new) and an old friend who has had a territory close to the field station for the three subsequent years. However, this season he ended up alone.  Slowly however, more individuals showed up. One male I was very exited to see again. Also he has kept his territory since the beginning of the project in 2014. What makes him extra special is that he used the same exact nest scrape for three years in a row. This year there was a new scrape, but located only ten meters from the previous one.

Measuring the wing area, one of the many measurements taken.
The first bird was caught short after incubation had started. Following that most birds in the valley where caught except for the lonely male. Right after midsummer several waders were seen on the lakeshore. Among them the first Ruffs ever observed in Latnjajaure, a small flock of Common Ringed Plover and the first Dotterel for the season. This individual came flying on high altitude through the valley. That behaviour together with the flocking behaviour of the plovers made me draw the conclusion that these were failed breeders moving towards initial staging areas.

Not long before the first helicopter back to Abisko was going I stumbled upon a new nest. It turned out that both the male and the female was ringed and logger at a previous year. The female carried a logger that were deployed in 2015, which means that it could potentially contain data from two consecutive years! Due to these and a couple of days of bad weather, which did not give any opportunity for trapping, I missed the helicopter. 
Bad weather in the summer could mean snow in the mountains.
After a couple of trapping attempts a few days later I managed to retrieve both loggers. After making sure, to the best of my ability, that there was no more breeding pairs I hiked back to Abisko with a total of four geolocators to be analysed when coming back to Lund.

The fantastic bird life in the area is not the only thing that amazes. This is a Diapensia lapponica, a resistant pincushon plant that each year survives thick snow cover, freezing and thawing during the flowering period, and trample by reindeers. This particular clone is a real champion since it is, judged by the size, about 800 years old. Maybe it started its life during Marco Polo adventures in eastern Asia?

 Amazing morning at Torneträsk, in Abisko, after coming down from Latnjajaure.

/Linus Hedh

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