Poster Details
SUMMARY OF INSECT EMERGENCE FROM FINDLEY LAKE IN THE CONIFEROUS FOREST OF THE CASCADE MOUNTAINS, USA
Insects were collected in floating emergence traps on oligotrophic Findley Lake. The biomass that emerged in 1973 after an early thaw on 7 June was more than in 1974 after a late thaw on 31 July. Procladius and Orthocladius (Diptera: Chironomidae), Apatania zonella (Trichoptera: Apataniidae) and Suwallia pallidula (Plecoptera: Chloroperlidae) started to emerge from the sites that thawed early, even though the rest of the lake was still covered with ice. There was a large emergence of the zooplanktivore Chaoborus trivittatus (Diptera: Chaoboridae) each year which peaked only nine to thirteen days after the entire fishless lake had thawed. The detritivores Clistoronia magnifica, Limnephilus santanus and Halesochila taylori (Trichoptera: Limnephilidae) emerged from deeper water after an early thaw than after a late thaw. C. magnifica, L. santanus and Hesperophylax designatus (Limnephilidae) emerged during the summer stratification. H. taylori emerged at the start of the fall mixing. Ephemeroptera emerged from most depths during the fall mixing, except near some wet meadows. Somatochlora albicincta (Odonata: Corduliidae) emerged from the shore near the wet meadows each year. Aeshna palmata (Odonata: Aeshnidae) emerged from the entire shore in warm years.
Truman Sherk (Primary Presenter/Author), retired, tsherk@gmail.com;
Greg Rau (Co-Presenter/Co-Author), retired, ghrau@sbcglobal.net;