Skip to Main Content
Due to a lapse in federal funding, this USDA website will not be actively updated. Once funding has been reestablished, online operations will continue.
An emergent multiple predator effect may enhance biotic resistance in a stream fish assemblageAuthor(s): Bret C. Harvey; Jason L. White; Rodney J. Nakamoto
Source: Ecology 85(1): 127-133
Publication Series: Miscellaneous Publication
PDF: View PDF (250 KB)
DescriptionWhile two cyprinid fishes introduced from nearby drainages have become widespread and abundant in the Eel River of northwestern California, a third nonindigenous cyprinid has remained largely confined to <25 km of one major tributary (the Van Duzen River) for at least 15 years. The downstream limit of this species, speckled dace, does not appear to correspond with any thresholds or steep gradients in abiotic conditions, but it lies near the upstream limits of three other fishes: coastrange sculpin, prickly sculpin, and nonindigenous Sacramento pikeminnow. We conducted a laboratory stream experiment to explore the potential for emergent multiple predator effects to influence biotic resistance in this situation. Sculpins in combination with Sacramento pikeminnow caused greater mortality of speckled dace than predicted based on their separate effects. In contrast to speckled dace, 99% of sculpin survived trials with Sacramento pikeminnow, in part because sculpin usually occupied benthic cover units while Sacramento pikeminnow occupied the water column. A 10-fold difference in benthic cover availability did not detectably influence biotic interactions in the experiment. The distribution of speckled dace in the Eel River drainage may be limited by two predator taxa with very different patterns of habitat use and a shortage of alternative habitats.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
CitationHarvey, Bret C.; White, Jason L.; Nakamoto, Rodney J. 2004. An emergent multiple predator effect may enhance biotic resistance in a stream fish assemblage. Ecology 85(1): 127-133
Keywordsbiotic resistance, Cottidae, cover, Cyprinidae, emergent multiple predator effects, introduced species, laboratory stream, predation risk, stream fish
- Effects of an introduced piscivorous fish on native benthic fishes in a coastal river
- Basin-scale patterns in the drift of embryonic and larval fishes and lamprey ammocoetes in two coastal rivers
- Habitat relationships and larval drift of native and nonindigenous fishes in neighboring tributaries of a coastal California river
XML: View XML