Doctoral Degrees (Conservation Ecology and Entomology)

Permanent URI for this collection

https://scholar.sun.ac.za/handle/10019.1/531

Browse

Browsing Doctoral Degrees (Conservation Ecology and Entomology) by Author "Achiano, K. A. (Kwaku Akoming)"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Carcinops pumilio (Erichson) (Coleoptera: Histeridae) as a predator of house flies in poultry manure
    (Stellenbosch : Stellenbosch University, 2004-04) Achiano, K. A. (Kwaku Akoming); Giliomee, J. H.; Stellenbosch University. Faculty of Agricultural and Forestry Sciences. Dept. of Entomology and Nematology
    ENGLISH ABSTRACT: In surveys carried out on poultry farms in the Western Cape Province, South Africa, the larvae of the flies Musca domestica L., Fannia canicularis (L.) and Leptocera sp. were found to be numerous. The majority of M domestica larvae and the mite Proctolaelaps sp. were recovered from manure with temperatures between 20 and 26°C while the larvae of F. canicularis and Leptocera sp. were mostly found between 14 and 22°C. Predominant predatory arthropods in the manure were the histerid Carcinops pumilio (Erichson), the staphylinid Philonthus sordidus (Gravenhorst) and the mite Macrocheles muscaedomesticae (Scopoli). These had a manure temperature tolerance of between 12 and 31°C. Macrocheles muscaedomesticae and P. sordidus preferred fresh manure, whilst C pumilio preferred aged manure. Therefore these two predators could complement one another in integrated pest management programmes. From a study of the vertical cross-sectional profile of the manure cone it was clear that the larvae of the prey species M domestica and F. canicularis and predator P. sordidus distinctly occupy the crest of the manure cone. The succession of arthropods in accumulating poultry manure and the effect of manure height on their numbers was studied. The prey species M domestica and F. canicularis were the first colonizers followed by the predators P. sordidus and M muscaedomesticae. Carcinops pumilio was a late colonizer. The numbers of M domestica and F. canicularis larvae were negatively correlated with the increase in manure height whilst the numbers of the predators C pumilio and M muscaedomesticae were positively correlated with this. The total developmental time of C pumilio from egg to adult emergence at 30°C was 20.5 days. Two larval instars were recorded. The immature stages sustained about 50% mortality before adult emergence. Carcinops pumilio adults can live up to 130 days at 30°C and had a Type I survivorship curve. The intrinsic rate of natural increase (rm) was 0.064943 and net reproduction rate (Rs) was 20.191.The rate of oviposition was directly proportional to body size and weight. Increase in density had a dampening effect on fecundity and led to an increase in developmental time. Thus density will be a critical factor in any mass rearing programme for this predator of fly larvae. In addition, an increase in density stimulated the dispersal of C. pumilio. A crowding level of 50 C. pumilio adults per 200ml container resulted in the least dispersal which did not exceed 2.5% per day, compared with up to 24.0% at a crowding level of 400. The predation rate of flies by C. pumilio in the laboratory decreased with an increase in predator density, but increased with an increase in starvation. Starvation had no effect on predation rate of M muscaedomesticae. A technique exploiting Drosophila melanogaster Meig. as a source of prey was successfully developed for rearing C. pumilio, which could be of commercial value. Drosophila melanogaster appeared to be an ideal candidate as a source of prey for mass rearing C. pumilio due to its short developmental time of about ten days. It is also inexpensive and easy to breed, and has a very high biotic potential. Carcinops pumilio that were fed on artificial diet had a prolonged developmental time and increase in weight, and laid fewer eggs than those fed on natural diet. C. pumilio completed its development on the artificial diet and both the F, and F2 generations fed on an artificial diet were able to lay eggs. This could be the first step towards finding an artificial diet that would allow continuous rearing of C. pumilio and their availability at all times for utilization in the biological control of houseflies.