Ambient oxygen tension, metabolic rate, and habitat selection in freshwater snails
Hanley, Robert; Ultsch, Gordon R.
Archiv für Hydrobiologie Volume 144 Number 2 (1999), p. 195 - 214
published: Jan 22, 1999
ArtNo. ESP141014402002, Price: 29.00 €
The relationship between ambient oxygen tension (PO2) and metabolic rate (VO2) in freshwater snails was examined in order to determine if habitat selection is influenced by hypoxia tolerance. Laboratory and field data were collected on 11 species from lotic and lentic habitats. Metabolic rates were determined at 15 and 25 °C using a closed respirometer technique. In 3 of 20 cases, species were judged to be metabolic O2 conformers, in 8 of 20 to be metabolic O2 regulators, and in 9 of 20 to have two zones of metabolic O2 conformation, with the zone in the higher range of PO2 being characterized by less fall in VO2 with declining PO2 than in the zone in the lower range of PO2. We conclude that the response of aquatic VO2 to hypoxia among snails can not be predicted by any single taxonomic, ecological, or physiological classification.