Abstract
During sporadic outbreaks of S. exempta, population densities sometimes reach extremely high numbers. Monitoring at one such outbreak revealed that a considerable synchrony exists in the developmental processes of such populations, so that at times up to 97% of the population is represented by only one stage of development. Heavy pupal mortality with symptoms of a cytoplasmic virus infection was noted. Flight behaviour of emerging adults revealed observable differences in the flight activity of the moths. Although a great majority of the emerging moths flew away from the area, some stayed back. Eggs layed by the latter produced a second brood but, due to a more or less total depletion of the food source, this subsequent brood did not survive in any appreciable numbers and finally died out.
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Khasimuddin, S. Behavioural Ecology of the African Armyworm, Spodoptera Exempta (Walker): Observations on Population Processes During a High-Density Outbreak. Int J Trop Insect Sci 1, 143–146 (1980). https://doi.org/10.1017/S1742758400000308
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DOI: https://doi.org/10.1017/S1742758400000308