Crustacean Plankton of 146 Alpine and Subalpine Lakes and Ponds in Western Canada

Abstract

Investigations of crustacean plankton communities in 146 alpine and subalpine waters in some western Canadian national parks and environs showed that species composition varied little from year to year and that there was a mean of 2.93 species per community Diaptomus arcticus occurred in 60% of the communities. More cladoceran species than copepod species were found, but there were usually more copepod than cladoceran species in a community. Many of the species found in subalpine waters did not occur in alpine waters, where they were probably limited more by physical factors — such as temperature and morphometry — and the presence of large predators than by altitude. Except for anostracans, few species seemed to be restricted to either lakes or ponds in the study area. Congeneric occurrences of large cladocerans or nonpredaceous diaptomid copepods were uncommon, as were co-occurrences of large cladocerans and nonpredaceous diaptomids.