An insect introduction to the maritime Antarctic

摘要: Although several invertebrates have been introduced by Man into the Antarctic, no holometabolous insects survived to colonize terrestrial habitats successfully. Data are presented on survival of populations a chironomid midge, together with an enchytraeid worm, for 17 years in maritime Antarctic site at Signy Island, South Orkney Islands. Both species thought plant material transplanted from either Georgia or Falkland Islands both 1967. Population densities average 25718m-2 dipteran larvae and 3243 m-2 worms. Successful completion midge's life cycle was indicated emergence brachypterous adults oviposition (the population is parthenogenetic only females present). taxa capable supercooling between -13 -26°C, this capacity may not be sufficient severe winter avoid lethal freezing. Four potential cryoprotectants were found insect extracts, but concentrations (< 1 % fresh weight) unlikely influence cold hardiness. appear pre-adapted much harsher conditions than they normally experience, extension existing physiological mechanisms. It concluded that main limitations invertebrate colonization suitable land areas soil-dwelling geographical.