Excuse me, as what?
VINCERO= Viruses In Northern Cyclic EpiRrita and Operophtera populations
The last two years were hard on the mountain birches especially at Abisko (Sweden) and Kilpisjärvi (Finland) due to defoliation by Epirrita autumnata and Operophtera brumata. Densities of the two geometrids were extremely high in 2013 marking the peak of their 9-10-year cyclic fluctuations. High densities made our sampling under CAPISCO easy, but many of our samples died of a suspected virus disease. This led us collaborating with virus experts at our institute (O. Terenius & J. De Miranda, Swedish University of Agricultura Sciences), who confirmed our suspicions of a virus causing the loss of our larvae.
The virus(es) seem to occur especially at high density populations, but its/their role in the cyclic population dynamics is not known. Therefore, we took up the challenge of revealing the link between virus and cyclicity and hope to win (vincere – vincero)!
And what about this year?
This year, we will again sample our sites at Abisko (Sweden), Gratangen (Norway), Kilpisjärvi (Finland), Kevo (Finland), Nuorgam (Finland) and Neiden (Svanhovd, Norway). We started our trip on June 12th from Abisko, and it seems that densities there and at Kilpisjärvi are in decline, although still fairly high. We hoped to get a lot of material for the virus experts, and indeed, already now, some of our larvae from Abisko have died of suspected virus disease.
Being back on the road, we will sample from a wide range of population densities, and hope to see where and when virus occurs. In addition, we shall report you on what it feels like to cross the borders and time zones numerous times (can’t keep track how many…) and drive in various conditions.
Helena and Tea