NEGATIVE BINOMIAL-DISTRIBUTION AS A MODEL FOR FLEAS ON SMALL RODENTS

The occurrence of fleas (Siphonaptera) as a group, as well as the spec ies Ctenophthalmus agyrtes on Apodemus flavicollis and Clethrionomys g lareolus in submontane and lowland conditions was analysed. The comput ed indices of aggregation (variance-to-mean, standardised Morisita ind ex, k of the negative binomial, index of discrepancy) indicated that a ll subsets of the data were aggregated. The frequency distribution of fleas and C. agyrtes on small rodents could in most cases be described as negative binomial.