Year Report 2016

DRAGONFLIES

  • In 2016, I extended my dragonfly research to an inventory of dragonfly exuviae. Still, I also made some dragonfly adult observations, but not too many. As usual, I also studied the butterfly community along Liesjärvintie.
  • For the dragonfly exuviae research I visited 10 different waterbodies (9 lakes and 1 river). In total I collected and identified 365 larval skins of 15 (+ 1 Zygoptera = 16) dragonfly species, which are almost all the species (19 species) that I observed during the previous eleven years. This year I also discovered two species new to the area: Liitokorento (Epitheca bimaculata) and Suoukonkorento (Aeshna subarctica). Of Liitokorento, first, I found its’ exuviae, thereafter also one adult.
  • In addition, I measured the electric conductivity  (EC) and the pH of all sampling locations. To my surprise there was not much variation in EC and pH between the various water bodies. Only one small lake (Peräjärvi) had a strongly deviating EC (96 uS) which was much higher than the EC at the other locations (19-35 uS). Maybe because of the surrounding agricultural landscape? The pH of the larger lakes in forest areas was about 7. The small lakes in peat bog areas were more acid (pH=6).

BUTTERFLIES

  • Most of the common butterflies were present in the summer of 2016, except for Pihlajaperhonen (Aporia crataegi).
  • We observed more Keisarinviitta (Argynnis paphia) then in any of the previous years since 2011 (= first year present in Liesjärvi).