Abstract
A description is given of variations found in the life-cycles and local differences in weight of the leech E. octoculata from five different reaches of the River Trent which were subjected to different levels of pollution, mainly in the form of domestic sewage, and to different temperature regimes produced by the condenser effluents from four Power Stations.
In reaches receiving high levels of sewage pollution the mean weights of leeches were higher than in relatively unpolluted reaches (P < 0.001). This increase could have been produced by the abundance of tubificid worms present in the polluted reaches, the worms providing a ready food supply for the leeches.
Earlier emergence of newly hatched leeches which occurred at some of the sampling points was probably caused by the combined or separate effects of the increased temperatures below condenser effluents and the earlier production of cocoons induced by the greater availability of food organisms in the more polluted reaches.
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Bibliography
Alabaster, J. S., Garland, J. H. N. & Hart, I. C. - 1971 - Fisheries Cooling Water Discharges and Sewage and Industrial Wastes, Memorandum No. RD/L/M 312.
Aston, R. J. - 1973 - Field and Experimental Studies on the Effects of a Power Station Effluent on Tubificidae (Oligochaeta, Annelida). Hydrobiologia 1 42, 225–243.
Elliott, J. M. - 1973 - The life-cycle and production of the leech Erpobdella octoculata (L) (Hirudinea: Erpobdellidae) in a Lake District Stream. J. Anim. Ecol. 42, 435–448.
Elliott, J. M. - 1973 - The diel activity pattern, drifting and food of the leech Erpobdella octoculata (L) (Hirudinea: Erpobdellae) in a Lake District Stream. J. Anim. Ecol. 42, 449–259.
Howmiller, R. P. - 1971 - Effects of Some Common Preservatives on the Weight of Tubificid Worms and Chironomid Larvae. Report Center for Great Lakes Studies, Univ Wisconsin - Milwaukee.
Langford, T. E. - 1970 - The Temperature of a British River Upstream and Downstream of a Heated Discharge from a Power Station. Hydrobiologia 35, 353–375.
Mann, K. H. - 1953 - The life History of Erpobdella octoculata (Linnaeus 1758). J. Anim. Ecol. 22, 199–207.
Mann, K. H. - 1961 - The Life History of the Leech Erpobdella testacea and its adaptive significance. Oikos, 12, 164–169.
Mann, K. H. - 1964 - A Key to the British Freshwater Leeches. Sci. Pub. No. 14 F.B.A.
Mann, K. H. - 1967 - Limnofauna Europaea. Edited by Joachim Illies. Gustav Fischer, Verlag, Stuttgart
Ross, F. F. - 1958 - The Operation of Thermal Power Stations in Relation to Streams, Annual Conf. Inst. Sew. Purif. June (1958).
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ston, R.J., rown, D.J.A. Local and seasonal variations in populations of the leech erpobdella octoculata (L) in a polluted river warmed by condenser effluents. Hydrobiologia 47, 347–366 (1975). https://doi.org/10.1007/BF00039582
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DOI: https://doi.org/10.1007/BF00039582