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.
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.
Amazing morning at Torneträsk, in Abisko, after coming down from Latnjajaure. |
/Linus Hedh
2017-07-06
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