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The population dynamics of Lepeophtheirus pectoralis (Müller): dispersion pattern

Published online by Cambridge University Press:  06 April 2009

G. A. Boxshall
G. A. Boxshall
Affiliation:
Wellcome Marine Laboratory and The Department of Pure and Applied Zoology, University of Leeds, Leeds, LS2 9JT
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Extract

The numerical relationships between a population of Lepeophtheirus pectoralis and its host population (plaice) have been described. There was no significant difference between infection levels in male and female plaice. In most of the monthly samples (75%) there was no significant relationship between host length and either the incidence or intensity of infection. The samples in which significant positive correlations occurred were usually taken within the period November to April. It is probable that the immigration of smaller fish, with lower levels of infection, from shallower water produces this effect.

The parasite population was found to have an overdispersed distribution (variance > mean) within its habitat, the host population. The frequency distributions of numbers of parasites per fish were calculated and the negative binomial distribution was fitted to these. The fit was good in 22 of the 24 samples and the value of k, the exponent, was found to be directly related to the mean density of the parasite population. Iwao's (1970) method of dispersion analysis indicated that the observed negative binomial was generated by a model of randomly distributed clumps or colonies of individuals. A possible mechanism of producing this pattern was proposed based on evidence from studies of mortality in the parasite population (which indicated that all-or-none type mortality operates on the clumps at certain periods during the year), the infection process (which demonstrated that a single wave of infection produces an overdispersed spatial distribution) and the examination of parasites from individual fish (which displayed a clumping of parasites at certain stages rather than an even spread over the range of possible stages). The mechanism proposed is that the adaptations for host location of the infective copepodid stage tend to produce aggregations of these larvae in favourable areas of a heterogeneous habitat. Fish moving randomly into these areas will tend to be infected by more than one larva (a clump of larvae) at any one time when available for infection. The fish can be regarded as equivalent to random samples of the free larval population and the aggregated distribution of the parasite population on its hosts is therefore directly related to the aggregated distribution of the free-swimming infective larvae.

Type
Research Article
Information
Parasitology , Volume 69 , Issue 3 , December 1974 , pp. 373 - 390
Copyright
Copyright © Cambridge University Press 1974

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References

REFERENCES

Anscombe, F. J. (1950). Sampling theory of the negative binomial and logarithmic series distributions. Biometrika 37, 358–82.CrossRefGoogle ScholarPubMed
Bliss, C. I. & Fisher, R. A. (1953). Fitting the binomial distribution to biological data and a note on the efficient fitting of the negative binomial. Biometrics 9, 176–200.Google Scholar
Boxshall, G. A. (1974). The population dynamics of Lepeophtheirus pectoralis (Müller): seasonal variation in abundance and age structure. Parasitology 69, 361–71.Google Scholar
Cable, R. M. (1972). Behaviour of digenetic trematodes. In Behavioural Aspects of Parasite Transmission (ed. Canning, E. U. and Wright, C. A.), pp. 1–18. Supplement no. 1 to the Zoological Journal of the Linnean Society.Google Scholar
Crofton, H. D. (1971). A model of host–parasite relationships. Parasitology 63, 343–64.CrossRefGoogle Scholar
Elliot, J. M. (1971). Some methods for the statistical analysis of samples of benthic invertebrates. Scientific Publication of the Freshwater Biological Association, no. 25.Google Scholar
Fisher, R. A. & Yates, F. (1949). Statistical Tables for Biological, Agricultural and Medical Research. Edinburgh and London: Oliver and Boyd.Google Scholar
Griffiths, K. J. & Holling, C. S. (1969). A competition sub-model for parasites and predators. The Canadian Entomologist 101, 785–818.Google Scholar
Holling, C. S. & Ewing, S. (1969). Blind man's buff: exploring the response space generated by realistic ecological simulation models. In Statistical Ecology, Vol. 2. Sampling and Modeling Biological Populations and Population Dynamics (ed. Patil, G. P., Pielou, E. C. and Waters, W. E.), pp. 207–30. University Park and London: Pennsylvania State University Press.Google Scholar
Iwao, S. (1970). Problems of spatial distribution in animal population ecology. In Random Counts in Scientific Work, vol. 2 (ed. Patil, G.), pp. 117–49. Pennsylvania State University Press: University Park and London.Google Scholar
Iwao, S. & Kuno, E. (1971). An approach to the analysis of aggregation pattern in biological populations. In Statistical Ecology. Vol. 1. Spatial Patterns and Statistical Distributions (ed. Patil, G. P., Pielou, E. C. and Waters, W. E.), pp. 461–513. University Park and London: Pennsylvania State University Press.Google Scholar
James, B. L. & Srivastava, L. P. (1967). The occurrence of Podocotyle atomon (Rud., 1802) (Digenea), Bothriocephalus scorpii (Müller, 1776) (Cestoda), Contracoecum clavatum (Rud., 1809) (Nematoda) and Echinorhynchus gadi Zoega, in Müller, 1776 (Acanthocephala) in the five-bearded rockling, Onos mustela (L.). Journal of Natural History 1, 363–72.CrossRefGoogle Scholar
Kearn, G. C. (1967). Experiments on host-finding and host-specificity in the monogenean skin parasite Entobdella soleae. Parasitology 57, 585–605.CrossRefGoogle ScholarPubMed
Li, S. Y. & Hsu, H. F. (1951). On the frequency distribution of parasitic helminths in their naturally infected hosts. Journal of Parasitology 37, 32–41.CrossRefGoogle ScholarPubMed
Lloyd, M. (1967). Mean crowding. Journal of Animal Ecology 36, 1–30.CrossRefGoogle Scholar
Mackenzie, K. (1968). Some parasites of O-group plaice, Pleuronectes platessa L., under different environmental conditions. Marine Research 3, 1–23.Google Scholar
Neyman, J. (1939). On a new class of ‘contagious’ distributions, applicable in entomology and bacteriology. Annals of Mathematical Statistics 10, 35–57.CrossRefGoogle Scholar
Pennycuick, L. (1971). Frequency distributions of parasites in a population of three-spined sticklebacks, Gasterosteus aculeatus L., with particular reference to the negative binomial distribution. Parasitology 63, 389–406.CrossRefGoogle Scholar
Polya, G. (1931). Sur quelques points de la théorie des probabilités. Annales de l'Institut Henri Poincaré 1, 117–61.Google Scholar
Scott, A. (1901). Lepeophtheirus and Lernaea. L.M.B.C. Memoirs on Typical British Marine Plants and Animals, no. 6.Google Scholar
Southwood, T. R. E. (1966). Ecological Methods. London.Google Scholar
Thomas, M. (1949). A generalization of Poisson's binomial limit for use in ecology. Biometrika 36, 18–25.CrossRefGoogle ScholarPubMed
Wickens, J. F. & MacFarlane, I. S. (1972). Some differences in the parasitic fauna of three samples of plaice (Pleuronectes platessa L.) from the southern North Sea. Journal of Fish Biology 4, 9–21.Google Scholar
Wimpenny, R. S. (1953). The Plaice. London: Arnold.Google Scholar