, Volume 208, Issue 3, pp 261–267 | Cite as

Recolonisation of four small streams in central Scotland following drought conditions in 1984

  • B. R. S. Morrison


Four streams in the Loch Ard Forest in central Scotland dried out almost completely during a drought in the summer of 1984. The recovery of the invertebrate populations in the streams was studied from September 1984 until March 1985 when most of the insect larvae and nymphs were almost full-grown.

The appearance of very small larvae belonging to several insect orders within a month of the streams' filling up suggests that they had survived the drought as eggs, or eggs had been laid by adults soon after the drought ended.

Statistical analysis showed that with the exception of 3 taxa there was no significant difference between the numbers of animals in November 1984 samples and in samples collected in March 1985.

Comparison of samples from March 1984 and March 1985 showed significant difference in population size for a few species; with 2 exceptions the 1984 samples (ie before drought) were larger. In the long term the overall effect of the drought on the invertebrate communities seems to have been limited.

Key words

stream benthos drought recolonisation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Cowx I. G., W. O. Young & J. M. Hellawell, 1984. The influence of drought on fish and invertebrate populations of an upland stream in Wales. Freshwat. Biol. 14: 165–177.Google Scholar
  2. Crichton M. J., D. Fisher & J. P. Woiwood, 1978. Life histories and distribution of British Trichoptera, excluding Limnephildae and Hydroptilidae, based on the Rothamstead Insect Survey. Holarct. Ecol. 1: 31–45.Google Scholar
  3. Elliott, J. M., 1977. Some methods for the statistical analysis of samples of benthic invertebrates. Freshwat. Biol. Ass. Scient. Publ. 25.Google Scholar
  4. Harriman, R. & B. R. S. Morrison, 1982. Ecology of streams draining forested and non-forested catchments in an area of central Scotland subject to acid precipitation. Hydrobiologia 88: 251–263.Google Scholar
  5. Harrison, A. D., 1966. Recolonisation of a Rhodesian stream after a drought. Arch. Hydrobiol. 62: 405–421.Google Scholar
  6. Hess, A. D., 1941. New limnological sampling equipment. Limnological Society of America, Special Publication no. 6: 1–5.Google Scholar
  7. Hynes, H. B. N., 1958. The effect of drought on a small mountain stream in Wales. Verh. int. Ver. theor. angew. Limnol 13: 826–833.Google Scholar
  8. Iversen, T. M., P. Wiberg-Larsen, S. B. Hansen & F. S. Hansen, 1978. The effect of partial and total drought on the macroinvertebrate communities of three small Danish streams. Hydrobiologia 60: 235–242.Google Scholar
  9. Morrison, B. R. S., 1978. Observations on the flight period of caddis flies (Trichoptera) at the Lake of Menteith, Perthshire. Entomologist's Rec. J. Var. 90: 38–41.Google Scholar
  10. Morrison, B. R. S., 1985. The influence of trees and water quality on fish and invertebrates in forest streams and lakes. In: Woodlands, Weather and Water (Eds. E. J. L. Harding & J. K. Fawell), Institute of Biology, London: 47–55.Google Scholar
  11. Townsend, C. R. & A. G. Hildrew, 1979. Form and function of the prey catching net of Plectrocnemia conspersa (Curtis) larvae (Trichoptera: Polycentropodidae) Oikos 33: 412–418.Google Scholar

Copyright information

© Kluwer Academic Publishers 1990

Authors and Affiliations

  • B. R. S. Morrison
    • 1
  1. 1.DAFS Freshwater Fisheries LaboratoryPitlochryScotland

Personalised recommendations