Poster Details
SEASONAL VARIATION IN CHIRONOMID COMMUNITIES IN TWO FAROESE STREAMS
The aim of this study was to compare the seasonal variation in chironomid communities in two adjacent streams in the Faroe Islands, with different environmental characteristics.
Streams in the Faroes are generally steep and very short, on average less than one kilometer in length. The basaltic bedrock is mostly impermeable to water, so precipitation runs off after a short retention time and the discharge fluctuates accordingly. The smaller streams do dry out in periods of little rainfall. The water temperatures vary from freezing in winter to 15 ºC on sunny days. The two streams sampled for this study were located a short distance from each other in neighbouring waterbasins,but differed in length and average discharge. Invertebrate samples were taken over the course of 14 months using a Surber sampler.
The invertebrate fauna in both streams was dominated by chironomids of the subfamily Orthocladiinae, with Eukiefferiella minor and Tvetenia sp. as the most abundant species. Peak of chironomid emergence was in the month of May. Chironomid density was higher in the small stream compared to the larger stream.
Leivur Janus Hansen (Primary Presenter/Author), Faroe Islands National Museum – Nature and Culture, janush@savn.fo;
Agnes-Katharina Kreiling (Co-Presenter/Co-Author), University of Iceland, kreiling@holar.is;
Gisli Mar Gislason (Co-Presenter/Co-Author), University of Iceland, gmg@hi.is;