|Recovery of zooplankton assemblages in mountain lakes from the effects of introduced sport fish|
Donald, D.B.; Vinebrooke, R.D.; Anderson, R.S.; Syrgiannis, J.; Graham, M.D. (2001). Recovery of zooplankton assemblages in mountain lakes from the effects of introduced sport fish. Can. J. Fish. Aquat. Sci. 58(9): 1822-1830
In: Canadian Journal of Fisheries and Aquatic Sciences = Journal canadien des sciences halieutiques et aquatiques. National Research Council Canada: Ottawa. ISSN 0706-652X, more
Populations; Populations; Predation; Species richness; Fresh water
|Authors|| || Top |
- Donald, D.B.
- Vinebrooke, R.D.
- Anderson, R.S.
- Syrgiannis, J.
- Graham, M.D.
Impacts of introduced fish on zooplankton assemblages of lakes may persist for decades following fish removal. We tested this hypothesis by comparing zooplankton assemblages from four categories of lakes located in western Canadian mountain parks including lakes without and with fish that differed in their fish community complexity and fish-stocking history. Zooplankton species richness was greatest in lakes with a complex community of fish and least in pristine fishless lakes. Canonical correspondence analysis showed that taxonomic shifts in zooplankton assemblages could be attributed to differences in fish-stocking history between the study lakes. In fishless lakes, larger copepods (Eucyclops agilis, Diaptomus leptopus), cladocerans (Diaphanosoma, large Daphnia), and chaoborids were abundant, whereas in the presence of fish, small crustaceans were more common and chaoborids were relatively rare. Once introduced trout were absent from lakes, recovery trajectories for zooplankton showed a general taxonomic shift towards assemblages characteristic of fishless lakes that had never been fish stocked. Based on separation between previously stocked fishless lakes and naturally fishless mountain lakes in ordination space (chi-squared distance), taxonomic recovery by zooplankton assemblages from the influence of introduced salmonids may require an average of 19 years.