The littoral Chironomidae (Diptera) of saline lakes in central British Columbia

Abstract

Collections of chironomid larvae, pupae, and adults were taken from the 1-m depth zone of 15 lakes of varying salinities in central British Columbia. Thirty-four species were identified.The littoral chironomid fauna of the lake series is divided into predominant associations whose existence seems to depend on salinity and productivity levels. A Cricotopus abanus – Procladius bellus association prevails in the lowest salinities (40 to 80 μmho/cm (1 mho = 1 S) conductivity) while in conductivities between 400 and 2800 μmho/cm a Glyptotendipes barbipes – Einfeldia pagana association predominates. In the most saline lakes (conductivity 4100 to 12 000 μmho/cm) a Tanytarsus gracilentus – Cryptotendipes ariel association is characteristic.Using these three chironomid associations it is possible to divide the 15 lakes into three groups. Waters with conductivities from 40 to 80 μmho/cm have chemical characteristics and a chironomid fauna distinct from those of higher salinities. The 10 lakes showing increasing conductivity (400 to 2800 μmho/cm) have physical, chemical, and biotic characters related to high productivity. In the particular case of this saline lake series, lakes with salinities about 3‰ (conductivity above 4000 μmho/cm) have a reduced productivity and a chironomid fauna characteristic of high salinities.

Salinity effects on macroinvertebrate assemblages and waterbird food webs in shallow lakes of the Wyoming High Plains

“…For example, chironomids were abundant in all lakes (Tables 3-6, Fig. 4), but the species composition probably changed with salinity (Cannings & Scudder, 1978). Nevertheless, decline of gastropods and amphipods indicates that important shifts in community structure occurred at the low end of the salinity range (cf., Williams et al, 1990).…”

Distribution and seasonal abundance of benthic macroinvertebrates in a subtropical Florida lake

“…Both chironomid and oligochaete communities, particularly those of the profundal zone, have been used as indicators of trophic state and/or pollution (e.g., Humphries, 1936;Brundin, 1949Brundin, , 1951Brundin, , 1956Brinkhurst, I966, I970a, b;Saether, 1975;J6nasson & Thorhauge, 1976;Cannings & Scudder, 1978;and Moore, 1978). This relationship between indicator organisms and lake type stems from differential tolerance of oxygen deficits by various species (Cannings & Scudder, 1978). Thus, the number of species and diversity of benthic invertebrate communities tend to decrease with depth in eutrophic lakes which stratify, even for short periods, during the summer.…”

Threads and Serendipity in the Life and Research of an Entomologist

“…I was also delighted to find that these water bodies contained a rich water boatman fauna, with a differential distribution that seemed to be linked to the water salinity. Over the following 14 years with the support of graduate-student research, the physical and chemical features of these saline lakes were documented (124), the biota therein was determined (7,8,44,60,61,83,104), and some aspects of their biology were investigated (9,122,123).…”