Population dynamics ofLuehdorfia japonica Leech (Lepidoptera: Papilionidae)

1. An adult population of a papilionid butterfly, Luehdorfia japonicaLeech , was studied by marking, release and recapture procedures in a hilly region in the suburbs of Kanazawa City, Japan.
2. Age of butterflies was estimated from the wing wear conditions, rated as winage categories 0 to 6.
3. Jolly (1965) andSeber's (1973) method was applied to the marking-recapture results for estimating the population parameters (sampling ratio, population size and survival rate).
4. Sampling ratio of males was consistently higher (around 50%) than that of females.
5. Newly emerged females were especially inactive, so that few of them were captured. From day 6.5 to day 10.0 they began to oviposit and became more active and more catchable.
6. An approximate sex ratio of 1∶1 was confirmed from the specimens collected in the field and by rearing experiments.
7. Daily survival rate was about 0.75–0.80 and mean longevity was about 4 days for both sexes. The maximum longevity observed was 17 days, for males and 21 days for females.
8. Dispersal by both sexes of the butterfly was more than 1 km.

     

A simulation study of population interaction between the greenhouse whitefly,Trialeurodes vaporariorum Westwood (Homoptera: Aleyrodidae), and the parasitoidEncarsia formosa gahan (Hymenoptera: Aphelinidae) I. Description of the model

A simple simulation model was developed to simulate the population dynamics of the system of the greenhouse whitefly (Trialeurodes vaporariorumWestwood ) and the parasitoid Encarsia formosaGahan . On the assumption that temperature is constant, the whitefly population was described as theLeslie Matrix model. Parasitization and host feeding by the parasitoid population were modelled by means of a modified disc equation. The validity of the model was demonstrated by comparing the predictions of the model with the observed values obtained in greenhouse experiments.