Effect of springtime water temperature on the time of emergence and size of Pteronarcys californica in the Henry's Fork catchment, Idaho, U.S.A.

Abstract

1. The emergence time of Pteronarcys californica in streams in the Henry's Fork catchment, Idaho, U.S.A. was negatively correlated with mean April water temperature. Emergence was in mid‐ to late May at sites influenced by groundwater, where April water temperature averaged 7.9 °C. Adults emerged in mid‐June in streams receiving run‐off from snowmelt (mean April water temperature 5.4 °C). Intermediate emergence times were observed in a regulated section of river where water temperature was influenced, on one bank, by dam release (mean April water temperature 4.5 °C) and, on the other, by a spring‐fed tributary stream (mean April water temperature 6.3 °C). 2. During each of the three study years, emergence was earlier on the bank of the regulated section that was warmer during April and May. The mean body length of P. californica exuviae, collected from the warm side of the river, averaged 1.2 mm longer than those collected from the cold side. 3. We tested the effect on emergence of altering springtime water temperature by translocating P. californica in cages from one location to another during April. Individuals moved to sites with higher April water temperature emerged earlier than individuals that remained at the site from which they were collected.

Invertebrate mesopredators are larger in streams with fish

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Increased growth and distribution of Ephemerella aurivillii (Ephemeroptera) after hydropower regulation of the Aurland catchment in Western Norway

“…Gregory et al (2000) found that April temperature was the best predictor for emergence of a Californian mayfly. Degree-day accumulation for egg incubation has been studied for several Australian mayfly species (Suter and Bishop, 1990;Brittain and Campbell, 1991;Brittain, 1995).…”

A new model estimating stonefly species production in the West Carpathian torrents

“…The larval growth of Nemouridae, Capniidae and Perlodidae in the Scandinavian stoneflies was largely positively influenced by water temperature (Brittain 1983). Water temperature affects the growth rate and emergence of stoneflies (Gregory et al 2000). Size of mature individuals depends on duration of larval development and growth rate, both of which are strongly influenced by temperature (Sweeney 1984;Perry et al 1987;Gregory et al 2000;Briers et al 2004;Krno, 2006).…”

“…Water temperature affects the growth rate and emergence of stoneflies (Gregory et al 2000). Size of mature individuals depends on duration of larval development and growth rate, both of which are strongly influenced by temperature (Sweeney 1984;Perry et al 1987;Gregory et al 2000;Briers et al 2004;Krno, 2006). Stonefly larval growth depended exponentially on water temperature (Elliot 1984(Elliot , 1987.…”