ナミアゲハ個体群の自然死亡率および死亡要因について
THE NATURAL MORTALITY AND ITS FACTORS OF THE IMMATURE STAGES IN THE POPULATION OF THE SWALLOW-TAIL BUTTERFLY PAPILIO XUTHUS LINNE

Yoshitaka TSUBAKI
1973 Nihon Seitai Gakkaishi  
The life tab 三 e studies were carried out Qn the first and the second generations of Papiiio xuthus population at Omura , Nagasaki. Natural and sem ト natura1 ( caged in the fie [ d)popula ・ tions were used in order to detect the cause and the rate of mortality in each of the develop ・ mental stages , such as egg , 行ve larval instars and pupa . The effect of predation was measured by comparing the two survival curves obtained from the caged 〔 5 mm net )and the uncaged populations . By this
more » ... ons . By this treatment , it was made c 】 ear that small predators { spiders , etc , 〕attacked the young larvae and large predators ( pohstes wasps , etc . ) attacked the later larvae . The high mortality rate during the later larval instars was mainly due to the predation , Egg mortality was mainly due to the egg parasite , Tn ' chogra " ima dendrol 吻 i. Three species of parasitic wasps , Reroiualus pupatum, 7》θ 9 螂 mactator , and β π zc乃珈 8 洳 obscurata emerged from the pupae . These egg and pupal parasites killed 24. 3 per cent of the eggs and 83per cent of the pupae in the f} rst generation , though with only slight eff t on the second generation . The difference in egg population density between the first ( 12. 7 eggs per 10 plants) and the second generation ( 3。 3 eggs per 10plants ) was partially explained by the difference in the mean fecundities of the adults 、 The mean fecundity per female was estimated as , M . E = ( L − iength of pre − ovipositional period ) × Mean number of eggs laid per day. The mean length of the adult life span 〔 L ) was given as follows , L ; 1/ ( 1 − K ) where K is the daily survival rate of the adult under the natura 】condition , and K is given as the soiution of the fo】 10wing equatlon , N7N = K α where N is the total number of adults in a generation and N ' is the number of adults iiving longer than cr days.
doi:10.18960/seitai.23.5_210 fatcat:hgze6kqmvvhlbefztglahy7vli