Hostname: page-component-77c89778f8-swr86 Total loading time: 0 Render date: 2024-07-16T21:47:04.508Z Has data issue: false hasContentIssue false
  • English
  • Français

Stability of Corynosoma populations with fluctuating population densities of the seal definitive host

Published online by Cambridge University Press:  05 October 2004

E. T. VALTONEN ,
E. HELLE  and
R. POULIN
E. T. VALTONEN
Affiliation:
Department of Biological and Environmental Science, University of Jyväskylä, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
E. HELLE
Affiliation:
Finnish Game and Fisheries Research Institute, P.O. Box 6, FIN-00721 Helsinki, Finland
R. POULIN
Affiliation:
Department of Zoology, University of Otago, P.O. Box 56, Dunedin, New Zealand
Get access Rights & Permissions [Opens in a new window]

Abstract

In theory there should be a strong coupling between host and parasite population sizes. Here, we investigated population size and structure in 3 species of acanthocephalans, Corynosoma semerme, C. strumosum and C. magdaleni, in ringed seals (Phoca hispida) from the Bothnian Bay over a period of more than 20 years. During this period, seal numbers first decreased markedly and then increased steadily; at the same time, a paratenic fish host particularly important for C. strumosum has gradually disappeared from the bay due to decreasing salinity. We found no evidence that the mean abundance of any of the 3 acanthocephalan species changed significantly over time, nor was there any relationship between parasite abundance at any point in time and seal numbers in the corresponding year. Based on the proportion of sexually mature female worms per infrapopulation, and on relationships between the sex ratio of worms and infrapopulation size, both C. magdaleni and C. semerme appear to be doing well, independently of the population size of their seal definitive hosts. In contrast, perhaps because of the loss of its main paratenic host, C. strumosum appears more at risk in the Bothnian Bay. Our results show that in complex natural systems, there are not necessarily simple, direct links between definitive host population size or density, and parasite population dynamics.

Keywords

stabilityacanthocephalan populationhost populationCorynosomaseals
Type
Research Article
Information
Parasitology , Volume 129 , Issue 5 , November 2004 , pp. 635 - 642
Copyright
© 2004 Cambridge University Press

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

ANDERSON, R. M. & MAY, R. M. ( 1978). Regulation and stability of host–parasite population interactions. I. Regulatory processes. Journal of Animal Ecology 47, 219–247.Google Scholar
ANDERSON, R. M. & MAY, R. M. ( 1979). Population biology of infectious diseases: part I. Nature, London 280, 361–367.CrossRefGoogle Scholar
BARYSHEVA, A. F. & BAUER, O. N. ( 1957). Fish parasites of Lake Ladoga. In Parasites and Diseases of Fish ( ed. Petrushevskii, G. K.), pp. 171–223. Bulletin of the All-Union Scientific Research Institute Fresh-water Fisheries. XLII, The Israel Program for Scientific Translations, Jerusalem.
CHUBB, J. C., VALTONEN, E. T., McGEORGE, J. & HELLE, E. ( 1995). Characterization of the external features of Schistocephalus solidus (Müller, 1776) from different geographic regions and assesment of the status of the Baltic ringed seal (Phoca hispida botnica) (Gmelin, 1785) as definitive host. Systematic Parasitology 32, 113–123.CrossRefGoogle Scholar
DELYAMURE, S. L., POPOV, V. N. & TRASHCHENKOV, A. N. ( 1980). A study of the helminth fauna of seals in the Baltic Sea and Lake Ladoga. Doklady Vysshei Shkoly, Biologicheskie Nauki 7, 43–45.Google Scholar
DONNER, J. ( 1995). The Quaternary History of Scandinavia. Cambridge University Press, Cambridge, UK.
HÄRKÖNEN, T., STENMAN, O., JUSSI, M., JUSSI, I., SAGITOV, R. & VEREVKIN, M. ( 1998). Population size and distribution of the Baltic ringed seal (Phoca hispida botnica). NAMMCO Scientific Publications I, 167–180.CrossRefGoogle Scholar
HÅRDING, K. C. & HÄRKÖNEN, T. ( 1999). Development in the Baltic grey seal (Halichoerus grypus) and ringed seal (Phoca hispida) populations during the 20th century. Ambio 28, 619–627.Google Scholar
HELLE, E. ( 1980). Aerial census of ringed seals Pusa hispida basking on the ice of the Bothnian Bay, Baltic. Holarctic Ecology 3, 183–189.CrossRefGoogle Scholar
HELLE, E. ( 1986). The decrease in the ringed seal population of the Gulf of Bothnia in 1975–84. Finnish Game Research 44, 28–32.Google Scholar
HELLE, E. & VALTONEN, E. T. ( 1980). On the occurrence of Corynosoma spp (Acanthocephala) in ringed seals (Pusa hispida) in the Bothnian Bay, Finland. Canadian Journal of Zoology 58, 298–303.CrossRefGoogle Scholar
HELLE, E. & VALTONEN, E. T. ( 1981). Comparison between spring and autumn infection by Corynosoma (Acanthocephala) in the ringed seal Pusa hispida in the Bothnian Bay of the Baltic Sea. Parasitology 82, 287–296.CrossRefGoogle Scholar
KOKKO, H., HELLE, E., LINDSTRÖM, J., RANTA, E., SIPILÄ, T. & COURCHAMP, F. ( 1999). Backcasting population sizes of ringed and grey seals in the Baltic and Lake Saimaa during the 20th century. Annales Zoologi Fennici 36, 65–73.Google Scholar
LEONARDSSON, K., ANDERSIN, A.-B., MÄKINEN, A. & RÖNNBERG, O. ( 1996). Benthic Biology. In Third Periodic Assessment of the State of the Marine Environment of the Baltic Sea, 1989–1993; Background Document. Baltic Sea Environment Proceedings No. 64B, 42–46.
MAY, R. M. & ANDERSON, R. M. ( 1978). Regulation and stability of host–parasite population interactions. II. Destabilizing processes. Journal of Animal Ecology 47, 249–267.Google Scholar
MAY, R. M. & ANDERSON, R. M. ( 1979). Population biology of infectious diseases: part II. Nature, London 280, 455–461.CrossRefGoogle Scholar
MONTREUIL, P. L. ( 1958). Corynosoma magdaleni sp. nov. (Acanthocephala), a parasite of the grey seal in eastern Canada. Canadian Journal of Zoology 36, 205–215.Google Scholar
NICKOL, B. B., HELLE, E. & VALTONEN, E. T. ( 2002). Corynosoma magdaleni in gray seals from the Gulf of Bothnia, with amended descriptions of C. strumosum and C. magdaleni. Journal of Parasitology 88, 1222–1229.Google Scholar
PETROCHENKO, V. I. ( 1956). Acanthocephala of Domestic and Wild Animals Vol. I: Izdatel'stvo Akademii Nauk SSSR, Moscow.
SINISALO, T. & VALTONEN, E. T. ( 2003). Corynosoma acanthocephalans in their paratenic fish hosts in the Northern Baltic Sea. Parasite 10, 227–233.CrossRefGoogle Scholar
SINISALO, T., KUNNASRANTA, M. & VALTONEN, E. T. ( 2003). Intestinal helminths of a landlocked ringed seal (Phoca hispida saimensis) population in the Eastern Finland. Parasitology Research 91, 40–45.CrossRefGoogle Scholar
SINISALO, T., POULIN, R., HÖGMANDER, H., JUUTI, T. & VALTONEN, E. T. ( 2004). The impact of sexual selection of Corynosoma magdaleni (Acanthocephala) infrapopulations in Saimaa ringed seals (Phoca hispida saimensis). Parasitology 128, 179–185.CrossRefGoogle Scholar
VALTONEN, E. T. ( 1983 a). On the ecology of Echinorhynchus salmonis and two Corynosoma species (Acanthocephala) in the fish and seals of the northern Gulf of Bothnia. PhD thesis. Acta Universitatis Ouluensis, Series A Scientiae Rerum Naturalium No. 156, Biologica 22, 1–49.
VALTONEN, E. T. ( 1983 b). Relationships between Corynosoma semerme and C. strumosum (Acanthocephala) and their paratenic fish hosts in the Bothnian Bay, Baltic Sea. Acta Universitatis Ouluensis, Series A Scientiae Rerum Naturalium No.155, Biologica 21, 1–32.
VALTONEN, E. T. & HELLE, E. ( 1988). Host–parasite relationships between two seal populations and two species of Corynosoma (Acanthocephala) in Finland. Journal of Zoology, London 214, 361–371.CrossRefGoogle Scholar
WIKNER, J. ( 1996). Gulf of Bothnia (Bothnian Bay, Bothnian Sea, Åland Sea, Archipelago Sea). In Third Periodic Assessment of the State of the Marine Environment of the Baltic Sea, 1989–93; Background document. Baltic Sea Environment Proceedings 64B, 28–46.Google Scholar