Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-26T00:46:53.325Z Has data issue: false hasContentIssue false

Notes on the biology of the copepod Mytilicola intestinalis Steuer

Published online by Cambridge University Press:  06 April 2009

J. N. R. Grainger
Affiliation:
From the Department of Zoology, University College, Hull

Extract

1. The free-swimming larvae of Mytilicola intestinalis can develop in theabsence of external food. Approximate figures are given for the duration of the free-living and early parasitic stages.

2. Four of the twenty-one samples of Mytilus edulis collected from various parts of Ireland were infected with Mytilicola intestinalis. All the four mussel beds found to be infected were in the neighbourhood of ports.

3. 72·0% of the Mytilicola which were found inhabited the part of the recurrent intestine which is embedded in the digestive gland.

4. There is a significant correlation between mussel length and number of Mytilicola per mussel.

5. There is a significant decrease in the numbers of Mytilicola per mussel between November to December and May to June. It is almost certain that this represents a real decrease in the copepod population, especially in the mussels larger than 55 mm., due to a death-rate which is sufficient to more than offset the increment due to new infection during November to January. In certain chosen size groups of mussels there is also an apparent decrease as a result of mussel growth in the summer, a time when new infection is very small.

6. In the 50–69 mm. mussel group the number of adult Mytilicola per mussel was lowest in September. The number of immature stages was highest in November and December and lowest from May to August. Egg-bearing copepods were found through out the year. There was an excess of males in the adult population throughout the year.

The writer is very indebted to the various people who assisted in collecting mussel samples especially the Irish Sea Fisheries Association; to Miss M. Davidson, B.A., who made a bacteriological examination of a mussel sample; to Dr J. P. Harding for informing him of the specimens of Mytilicola intestinalis in the British Museum collection; and to Prof. J. Brontë Gatenby and Dr J. D. Smyth of Trinity College, Dublin (where this work was carried out), for their suggestions and advice.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1951

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

Caspers, H. (1939). Zool. Anz. 126, 161.Google Scholar
Cole, H. A. (1948). Personal communication.Google Scholar
Ellenby, C. (1947). Nature, Lond., 159, 645.CrossRefGoogle Scholar
Monod, TH. & Dollfus, R. Ph. (1932). Ann. Parasit. hum. comp. 10, 129.CrossRefGoogle Scholar
Mori, T. (1935). Zool. Mag., Tokyo, 47, 689.Google Scholar
Pesta, O. (1907). Z. wiss. Zool. 88, 78.Google Scholar
Raymont, J. E. G. & Gross, F. (1942). Proc. roy. Soc. Edinb. B, 61, 267.Google Scholar
Sproston, N. G. & Hartley, P. H. T. (1941). J. Mar. biol. Ass. U.K. 25, 361.CrossRefGoogle Scholar
Steuer, A. (1902). Zool. Anz. 25, 635.Google Scholar
Steuer, A. (1905). Arb. zool. Inst. Univ. Wien, 15, 1.Google Scholar
Vayssière, A. (1914). In Caillol, H. & Vayasière, A., Zoogéographie in Les Bouches du Rhône. Encyclopédie départmental. 3° partie, Tome 12, p. 278. [Quoted from Monod & Dollfus (1932). Not seen in original.]Google Scholar
White, K. M. (1937). Mytilus. L.M.B.C. Memoirs, 31.Google Scholar
Wilson, C. B. (1938). J. Wash. Acad. Sci. 28, 284.Google Scholar