Salinity effects on macroinvertebrate assemblages and waterbird food webs in shallow lakes of the Wyoming High Plains
We determined the biomass and community structure of macroinvertebrates (>500 µm) associated with macrophytes, sediments, and unvegetated open water in three oligosaline (0.8 to 8.0 mS cm−1) and three mesosaline (8.0 to 30.0 mS cm−1) lakes in the Wyoming High Plains, USA. Total biomass of epiphytic and benthic invertebrates did not change with salinity, but biomass of macroinvertebrate zooplankton in open water was significantly higher in mesosaline lakes. Community composition of invertebrates differed between the two salinity categories: large grazer/detritivores (gastropods and amphipods) were dominant in oligosaline lakes, whereas small planktivores and their insect predators were more prevalent in mesosaline lakes. Both direct physiological effects of salinity, as well as a shift in the form of primary production from macrophytes to phytoplankton, probably explain these changes in community composition. Salinity effects on invertebrate communities appear to be less important to top avian consumers than are costs of osmoregulation.
Earth Systems Research Center
Digital Object Identifier (DOI)
Wollheim, W.M., and J.R. Lovvorn. 1995. Salinity effects on macroinvertebrate assemblages and waterbird food webs in shallow lakes of the Wyoming High-Plains. Hydrobiologia 310:207-223.
© Kluwer Academic Publishers 1995