青葉山におけるヒメギフチョウの発生生態と棲息地の植生環境

抄録

Luehdorfia puziloi (Lepidoptera: Papilionidae) is a monophagous univoltine butterfly; its adult flight period in Japan from April to May. Although the butterfly appears on the Japanese Red List (status: Near Threatened), detailed data about its ecology is insufficient to inform conservation decisions. Therefore, we estimate the survival rates in a population of L. puziloi on Mt. Aoba, Miyagi Prefecture using a modification of the Kiritani-Nakasuji-Manly method. The habitat is a deciduous broad-leaved forest dominated by Quercus serrta and its core is approximately 50 m long and 30 m wide. We surveyed the numbers of eggs and larvae in the habitat 11 times from April 10 to June 23,2005, and obtained the following estimates of daily survival rate: egg to the first instar larva, 0.98; first to second instar larva, 0.97; second to third instar larva, 0.96; third to fourth instar larva, 0.96; fourth to fifth instar larva, 0.90. We also obtained the following estimates of population size: 517 eggs; 440 first instar larvae; 362 second instar larvae; 243 third instar larvae; 225 fourth instar larvae; 111 fifth instar larvae. The estimated number of adults that emerged on April 15, 2006 were 14.3 based on a Bailey's triple catch method. Therefore if we assume that there were no migrant adults form other populations, the estimated survival rate from egg (517) to adult (14.3) was 2.8%.