The Effect of Fish Introductions on the Diatom and Cladoceran Communities of Lake Opeongo, Ontario, Canada

Abstract

Fish introductions are one of the most widespread anthropogenic perturbations to aquatic ecosystems. Paradoxically, the effects of these introductions on aquatic ecosystems are typically poorly documented. This project studied the effect of fish introductions on Lake Opeongo, an oligotrophic lake in Algonquin

The effect of fish stocking on mountain lake plankton communities identified using palaeobiological analyses of bottom sediment cores

“…The artificially introduced brook trout did not change this state, and even the higher density of fish in the lake did not affect the zooplankton. This finding is in contrast to the situation reported by Jacques et al (2005), who described a strong influence of cisco (Coregonus artedii Lesueur) on the density of Daphnia and an increase in the relative abundance of Bosmina longirostris. However, brook trout have food preferences similar to those of native brown trout and had no additional influence on zooplankton in MOK.…”

“…Fish stocking also indirectly causes an increase in nutrient contents and algal biomass (Carpenter et al 1995). A change occurs in the nutrient cycles supporting the growth of primary production by the assimilation and internal loading of phosphorus from the sediments, which is normally not available to pelagic communities in oligotrophic lakes (Jacques et al 2005). Phosphorus is one of the factors responsible for eutrophication of fresh water ecosystems (Katsaounos et al 2007).…”

Effects of a long term water level reduction on the ecology and water quality in an eastern Mediterranean lake

“…The cyprinids, such as roach (Rutilus rutilus), are well known to disturb the lake bottom and feed on large zooplankton (Lammens, 1999), enhancing thus the eutrophication and turbidity effects in lakes. On the other hand, the small sized Cladocerans, such as Bosmina spp., are less affected by fish predation and so they are able to maintain their numbers (St. Jacques et al, 2005). This appears to be the case in our study since the cladocerans were dominated by small sized Bosmina spp along with Chydorus sphaericus, although the high abundance of Chydorus sphaericus is related to the dense submerged vegetation (Mastrantuono and Mancinelli, 2005;Walseng et al, 2006) where the samplings were mostly conducted.…”

Using invertebrate remains and pigments in the sediment to infer changes in trophic structure after fish introduction in Lake Fogo: a crater lake in the Azores

“…Moreover, establishment of non-native and disappearance of native species cause biotic homogenisation of the fish fauna on a regional and global scale, threatening natural biodiversity (Lodge et al, 1998;Rahel, 2000). Still, effects of fish introduction on aquatic ecosystems are relatively poorly documented (Jacques et al, 2005). Remote, naturally fishless lakes are particularly well suited for studies of fish stocking and natural fish invasions.…”

“…Remote, naturally fishless lakes are particularly well suited for studies of fish stocking and natural fish invasions. Earlier findings have shown that sedimentary cladocerans and pigments can be indicators of changes in predation pressure by fish and zooplankton grazing and thus act as a useful tool for elucidating effects of fish introduction (Leavitt et al, 1994;Amsinck et al, 2005;Jacques et al, 2005;Buchaca & Catalan, 2007).…”