Zooplankton composition and ecology in western boreal shallow-water wetlands / J. Ivor Norlin, Suzanne E. Bayley, and Lisette C.M. Ross.

Includes bibliographical references (pages 214-215).

Zooplankton are a functionally important but poorly studied component of western boreal forest (WBF)
wetland ecosystems. To characterize patterns in zooplankton abundance and composition an exploratory
study of 24 shallow-water wetlands in northern Alberta, Canada was carried out over the summers of 2001
and 2002. Results suggest zooplankton communities in WBF wetlands tend to exist as: (1) small-cladoceran
dominated communities, (2) larger sized cladoceran (e.g. Daphnia) dominated communities, or (3) communities
composed primarily of rotifers and/or other crustacean zooplankton. The presence/absence of
brook stickleback (Culea inconstans) was the factor most strongly linked to zooplankton structure with
small cladocerans tending to dominate in wetlands with stickleback. In fishless wetlands, communities
dominated by medium-large sized cladocerans tended to correspond with low-chlorophyll/high-submerged
aquatic vegetation (SAV) conditions. Conversely, communities composed of rotifers and other crustaceans
were associated with high-chlorophyll/low-SAV states. Macro-invertebrate predator abundance was not
strongly linked to patterns in zooplankton composition suggesting macro-invertebrate predation is not a
significant factor influencing zooplankton structure in fishless wetlands. Results suggest activities that
spread stickleback (e.g. ditching) or inhibit development of macrophyte-dominated/clear-water conditions
(e.g. nutrient loading) may seriously alter the zooplankton community structure, and thereby the functional
ecology, of these valuable wetland ecosystems.