Impact of Embryonopsis halticella eaton larvae (Lepidoptera: Yponomeutidae) feeding in Marion Island tussock grassland

摘要: Embryonopsis halticella is a brachypterous moth endemic to the Kerguelen Province of sub-Antarctic islands. Its larvae are strictly host-specific grass-borers tussock grass Poa cookii, and major herbivores on Marion Island. Monthly sampling over one year (1984) Island showed that E. reach biomass 0.222 g m-2 (dry mass) in P. cookii grassland summer. In feeding experiments conducted laboratory Island, consumed 0.3 X their own live mass leaf material daily. Extrapolated consumption rates field range from 1 kg ha-1 month-1 winter 18 Total annual consumption, based only, amounts 86 mass). Significant shifts diet foliage seeds occur during spring, also consume frass exuviae. It calculated remove 2.5% production grassland.