Sympatry in four species of Rhinichthys (Pisces), including the first documented occurrences of R. umatilla in the Canadian drainages of the Columbia River

Autor: Grant W. Hughes, Alex E. Peden
Rok vydání: 1988
Předmět:
Zdroj: Canadian Journal of Zoology. 66:1846-1856
ISSN: 1480-3283
0008-4301
DOI: 10.1139/z88-267
Popis: Four species of Rhinichthys (R. cataractae, R. falcatus, R. osculus, and R. umatilla) are recognized in Canadian sections of the Columbia River, with sympatry occuring between all species except R. falcatus and R. osculus. Species status of the latter is supported by morphological dissimilarity between it and the morphologically similar R. falcatus and R. umatilla. Populations of R. umatilla from the Similkameen, Kettle, and Columbia (including Kootenay and Slocan) rivers have morphological and pigmentary differences, but are identifiable with R. umatilla of the lower Columbia River. Canadian R. osculus are similar to historically known populations near the Colville and Little Spokane rivers of northeastern Washington. Populations from more distant tributaries of the Columbia system are variable in morphology and habitat and require separate study to determine their relationships to Canadian populations. Rhinichthys osculus was apparently replaced by R. umatilla in the Colville River, an event that may have been correlated with historical changes of water quality or flooding by the Roosevelt Reservoir. Because R. umatilla prefers swift clear portions of large rivers, it is potentially in conflict with hydroelectric projects. Though not immediately threatened, the status of this species in Canada should be monitored in connection with future development of river systems.
Databáze: OpenAIRE