ISSN:
1365-2427
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
SUMMARY. 1. During two, 1-month studies, the abundance of mayfly nymphs, Callibaetis californicus Banks, in small ponds that contained the tadpole shrimp, Triops longicaudatus (LeConte), often was significantly lower than in ponds without tadpole shrimps. Mayfly abundance was either positively correlated or not significantly associated with that of predacious insects.2. Larger mayfly nymphs were a greater fraction of the population in ponds with Triops than in ponds without tadpole shrimps. Between 2 and 3 weeks after ponds were flooded, the smallest mayfly nymphs were absent from ponds in which T. longicaudatus densities were 〉5 individuals per square metre during the summer and 〉15 individuals per square metre during the autumn.3. In prey-choice trials, T. longicaudatus consumed predominantly small C. californicus nymphs (mean headwidth ± 1 SD: 0.44 ± 0.05 mm). After encounters with tadpole shrimps, small mayfly nymphs moved relatively shorl distances, were easily overtaken, and were, consequently, more susceptible to tadpole shrimps than larger-sized nymphs.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2427.1991.tb00480.x
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