Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-28T04:35:29.907Z Has data issue: false hasContentIssue false

The population dynamics of Lepeophtheirus pectoralis (Müller): seasonal variation in abundance and age structure

Published online by Cambridge University Press:  06 April 2009

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

Extract

The ectoparasitic copepod Lepeophtheirus pectoralis exhibited a regular annual cycle of abundance on its hosts. Both the incidence and intensity of infection were greatest in August or September and both declined over winter to their minimum values in April. Very similar cycles were observed in both 1972 and 1973. Analysis of the age structure of the parasite population showed that the increase in abundance coincided with the onset of the breeding season. Although females always outnumbered males the sex ratio approached unity during the breeding season, which extended from May to October. Copulating pairs were most commonly observed during this period.

There was a marked bimodal peak of egg production each year, with the first mode occurring around May and the second mode around August or September. This pattern was produced by a system of alternation of generations operating within the parasite population, with a summer type generation (distinguishable by its rapid maturation rate and reduced longevity) alternating with an overwintering type of generation.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1974

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Boxshall, G. A. (1974 a). Infections with parasitic copepods in North Sea marine fishes. Journal of the Marine Biological Association of the United Kingdom 54, 355–72.CrossRefGoogle Scholar
Boxshall, G. A. (1974 b). The developmental stages of Lepeophtheirus pectoralis (Müller, 1776) (Copepoda: Caligidae). Journal of Natural History 8, (in the Press).CrossRefGoogle Scholar
Boxshall, G. A. (1974 c). The population dynamics of Lepeophtheirus pectoralis (Müller): dispersion pattern. Parasitology 69, 373–90.CrossRefGoogle ScholarPubMed
Crofton, H. D. (1971). A quantitative approach to parasitism. Parasitology 62, 179–93.CrossRefGoogle Scholar
Deevey, G. B. (1960). Relative effects of temperature and food on seasonal variation in length of marine copepods in some Eastern American and Western European waters. Bulletin of the Bingham Oceanographic Collection, Yale University 17, 5586.Google Scholar
Grabda, J. (1963). Life cycle and morphogenesis of Lernaea cyprinacea L. Acta Parasitologia Polonica 11, 169–98.Google Scholar
Marshall, S. M. & Orr, A. P. (1955). The Biology of a Marine Copepod. Edinburgh and London: Oliver and Boyd.Google Scholar
McLaren, I. A. (1963). Effects of temperature on growth of zooplankton, and the adaptive value of vertical migration. Journal of the Fisheries Research Board of Canada 20, 685727.CrossRefGoogle Scholar
Scott, A. (1901). Lepeophtheirus and Lernaea. L.M.B.C. Memoirs on Typical British Marine Plants and Animals 6.Google Scholar
Tedla, S. & Fernando, C. H. (1970). On the biology of Ergasilus confusus Bere, 1931 (Copepoda) infesting yellow perch, Perca fluviatilis L., in the Bay of Quinte, Lake Ontario, Canada. Crustaceana 19, 114.Google Scholar
Wimpenny, R. S. (1953). The Plaice. London: Arnold.Google Scholar