After a short midsummer break we drove 400km north to Kevo research station at Utsjoki in Finland. The rain from Norway caught up with us and the thunder and lightning that came with it hit the transmission tower near the station cutting us (and half of the people in Utsjoki village) off the internet.
The lack of internet gave us more chance to talk with our colleagues, who told us, that, against expectations, the larval densities were really low around Kevo area. We noticed that out ourselves too when looking for suitable sampling sites despite the rainy weather.
Luckily the bad weather didn’t last through the next day and we were able to collect our specimens from Utsjoki. The mosquitoes had so far been absent, but now we got to use our “mosquito jackets” when hiking up the steep slope we had picked to be our transect. For anyone heading to northern Fennoscandia for the summer, we would warmly recommend these jackets in addition to some powerful mosquito repellent.
To our surprise we were able to find more larvae on the steep slope than we hoped for: our physical effort was not in vain! To anyone who’s wondering how fit we are, the rise was about 1 meter for each 2 meter advance uphill on the transect. Luckily the sauna in the evening washed away all the aches in our muscles and we even tested the water temperature at lake Kevojärvi by dipping in VERY quickly.
The ninth day was another travel day. Heading towards the Norwegian coast and Svanhovd (BioForsk) research station, we decided to make an extra stop at Nuorgam, where the first and latest winter moth (Operophtera brumata) outbreak in Finland occurred a couple of years ago. Almost all of the mountain birches looked dead and only a couple of trees here and there had green leaves.
We didn’t expect to find any larvae there, but we decided to try to sample there anyway. We got very lucky again finding both autumnal moth (Epirrita autumnata) and winter moth larvae. The view over the whole landscape with dead mountain birches was spectacular, and made us wonder about the overall consequences of defoliation this magnitude on the ecosystem.
-Tea & Helena-