A comparison of the population ecology of Asellus aquaticus (L.) and Asellus meridianus rac. in the reed beds of the Tjeukemeer
- 70 Downloads
The population ecology of Asellus aquaticus and Asellus meridianus was studied in a Tjeukemeer reed bed from March to October. The densities of the two species are similar at the beginning and end of the reproductive season, although A. meridianus is up to 3 times more abundant in between. In both species egg production is positively correlated to body length and summer brood sizes are smaller than in the spring. A. meridianus begins to reproduce at smaller sizes than A. aquaticus and is also more fecund for overlapping size classes. Over the season as a whole both species have the same reproductive output. The life cycles of the two species are very similar with three main periods of reproduction and the populations being replaced twice during the year. Despite the differences between the species no factors are found which gives one species an obvious competitive advantage against the other.
KeywordsAsellus aquaticus Asellus meridianus population dynamics life cycle competition
Unable to display preview. Download preview PDF.
- Andersson, E. 1969. Life cycle and growth of Asellus aquaticus with special reference to the effects of temperature. Rep. Inst. Freshwat. Res. Drottningholm 49: 5–26.Google Scholar
- Berglund, T. 1968. The influence of predation by brown trout on Asellus in a pond. Rep. Inst. Freshwat. Res. Drottningholm 48: 77–101.Google Scholar
- Berner, L. 1956. Note sur les Aselles d'eau douce. Arch. Hydrobiol. 51: 410–414.Google Scholar
- Edwards, R. W. & Learner, M. 1960. Some factors affecting the oxygen consumption of Asellus. J. exp. Biol. 37: 706–718.Google Scholar
- Haan, H. de. 1975. Limnologische aspecten van humusverbindingen in het Tjeukemeer. Doctoral Thesis, University of Groningen, 93 pages.Google Scholar
- Henry, J. P. & Magniez, G. 1970. Contribution à la systématique des asellides (Crustacea, Isopoda). Ann. Spéléol. 25: 335–367.Google Scholar
- Holthuis, L. B. 1956. Isopoda en Tanaidacea. Fauna Nederland 16: 1–280.Google Scholar
- Redeke, H. C. 1948. Hydrobiologie van Nederland. De zoete Wateren. de Boer, Amsterdam.Google Scholar
- Reynoldson, T. B. 1961. Observations on the occurrence of Asellus (Isopoda, Crustacea) in some lakes of Northern Britain. Verh. int. Verein. theor. angew. Limnol. 14: 988–994.Google Scholar