Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-25T17:04:55.612Z Has data issue: false hasContentIssue false

The biology of Echinocardium cordatum [Echinodermata: Spatangoidea] from different habitats

Published online by Cambridge University Press:  11 May 2009

John B. Buchanan
Affiliation:
Dove Marine Laboratory, University of Newcastle-upon-Tyne

Extract

An offshore and a littoral population of Echinocardium cordatum have been observed for a period of 7 years, starting from the time of their simultaneous larval settlement and establishment.

The littoral population was found in clean sand of low organic content. Individuals burrowed to a depth of 15 cm and could move through the sand at a speed of 6–8 cm/h. The test length increased at an average increment of 8 mm/annum. Breeding first took place in the third year and continued each year after.

The offshore population was found in very silty sand at depths of 30–40 m. Here individuals burrowed to a very shallow depth, 2 cm. or less, and moved very slowly through the sediment. The annual increment of test growth was only about 3 mm. Estimations showed that the littoral population had a production rate four times greater than the offshore. The offshore population did not reach sexual maturity during the period of observation. No new settlement was observed anywhere in the area during the period of observation.

The offshore population occurred in large discrete patches, each displaying a quantitatively concentric pattern with a central area of high density. Samples taken at single stations within the patch showed that the distribution was random for most of the year but that aggregations formed in June, July and August.

Both populations showed a steady mortality rate of about 15 % per annum and the longevity was estimated to be in the region of 15 years.

Based on prolonged aquarium observations of the feeding behaviour, reasons are given for believing that the surface collecting activities of the penicillate tube-feet of the anterior ambulacrum should be considered as a true feeding mechanism.

Type
Research Article
Copyright
Copyright © Marine Biological Association of the United Kingdom 1966

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

Buchanan, J. B., 1963. The bottom fauna communities and their sediment relation-ships off the coast of Northumberland. Oikos, Vol. 14, pp. 154–75.CrossRefGoogle Scholar
Chesher, R. H., 1963. The morphology and function of the frontal ambulacrum of Moira atropos. Bull. mar. Sci. Gulf Caribb., Vol. 13, pp. 549–73.Google Scholar
Clapham, A. R., 1936. Over-dispersion in grassland communities and the use of statistical methods in plant ecology. J. Ecol., Vol. 24, pp. 232–51.CrossRefGoogle Scholar
Hyman, L. H., 1955. Echinodermata. The Invertebrates, Vol. 4, 763 pp. New York.Google Scholar
Jones, M. L., 1961. A quantitative evaluation of the benthic fauna off Point Richmond, California. Univ. Calif. Publs Zool., Vol. 6, pp. 219320.Google Scholar
Moore, H. B., 1936. The biology of Echinocardium cordatum. J. mar. biol. Ass. U.K., Vol. 20, pp. 655–71.CrossRefGoogle Scholar
Nichols, D., 1959. Changes in the chalk heart-urchin Micraster interpreted in relation to living forms. Phil. Trans. R. Soc, B, Vol. 242, pp. 347437.Google Scholar
Orton, J. H., 1914. On the breeding habits of Echinus miliaris, with a note on the feeding habits of Patella vulgata. J. mar. biol. Ass. U.K., Vol. 10, pp. 254–7.CrossRefGoogle Scholar
Piper, C. C, 1947. Soil and Plant Analysis. Adelaide.Google Scholar
Robertson, D., 1871. Notes on Amphidotus cordatus (Perm.). Q. Jl microsc. Sci., Vol. 23 pp. 25–7.Google Scholar
Salt, G. & Hollick, F. S. J., 1946. Studies of wireworm populations. II. Spatial distribution. J. exp. Biol., Vol.23, pp. 146.CrossRefGoogle Scholar
Thorson, G., 1957. Bottom communities. In Treatise on Marine Ecology and Paleoecology. Mem. geol. Soc. Am., No. 67, pp. 461534.Google Scholar
Ursin, E., 1960. A quantitative investigation of the echinoderm fauna of the central North Sea. Meddr Kommn Havunders., N.S., Bd. 2, pp. 1204.Google Scholar