Document Type

Article

Publication Date

10-1987

Publication Title

Great Basin Naturalist

Volume

47

Issue

4

First page number:

538

Last page number:

546

Abstract

Critical thermal maxima (CTM) and thermal preferenda of the common fishes of the Virgin River were examined. Differences in final temperature preferenda and CTM for species with low thermal lability (speckled dace, spinedace, roundtail chub) correspond well with differences in their distribution and abundance in the river. These species shifted their acute thermal preferences relatively little as acclimation temperature increased. For thermally labile species (woundfin, red shiner, desert sucker, and fiannehnouth sucker), the final preferendum is a less precise indicator of probable distribution. The woundfin, an endangered fish, has a high CTM (39.5 C at 25 C acclimation) and a labile acute preferendum (slope nearest 1) compared to other species in the system. The introduced red shiner likewise has a high CTM and a labile acute preferendum. In cooler temperatures, its acute preferendum shifts more rapidly than does that of the woundfin. At higher temperatures (above 15 C), the red shiner does not shift its acute preferendum as rapidly as does the woundfin. The red shiner, however, has a higher final preferendum. For thermally labile species, influence of acclimation temperature on mean preferendum, together with CTM, provides a better insight into distributional relationships within the system.

Keywords

Aquatic ecology; Environmental quality; Freshwater fishes; Lake Mead (Ariz. and Nev.); Virgin River (Ariz.; Nev.; Utah); Water temperature

Disciplines

Aquaculture and Fisheries | Desert Ecology | Environmental Monitoring | Environmental Sciences | Fresh Water Studies | Life Sciences | Natural Resources and Conservation | Sustainability | Terrestrial and Aquatic Ecology

Language

English