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Effects of fish chemical cues on the interactions between tadpoles and crayfish

Nyström, Per LU and Åbjörnsson, Kajsa LU (2000) In Oikos 88(1). p.181-190
Abstract
We studied the effects of predatory crayfish (Pacifastacus leniusculus), the non-lethal effects of fish chemical cues (Oncorhynchus mykiss), and the combined effects of crayfish and fish chemical cues on the performance of tadpoles of two co-existing anuran species, Rana temporaria and Bufo bufo, in experimental pools. We also examined grazing effects on periphyton, the main food source for the tadpoles. Crayfish significantly reduced tadpole survival, particularly by feeding on Bufo. Rana benefited from reduced numbers of competitors, resulting from crayfish predation, by increased growth rate, whereas the growth rate of Bufo was unaffected by crayfish. The proportion of Rana in refuges (in relation to the number of survivors at the end... (More)
We studied the effects of predatory crayfish (Pacifastacus leniusculus), the non-lethal effects of fish chemical cues (Oncorhynchus mykiss), and the combined effects of crayfish and fish chemical cues on the performance of tadpoles of two co-existing anuran species, Rana temporaria and Bufo bufo, in experimental pools. We also examined grazing effects on periphyton, the main food source for the tadpoles. Crayfish significantly reduced tadpole survival, particularly by feeding on Bufo. Rana benefited from reduced numbers of competitors, resulting from crayfish predation, by increased growth rate, whereas the growth rate of Bufo was unaffected by crayfish. The proportion of Rana in refuges (in relation to the number of survivors at the end of the experiment) was unaffected by crayfish, whereas proportionally more Bufo stayed in refuges in the presence of crayfish, relative to controls. Fish cues had no effect on tadpole survival of either species. During the entire larval period, Rana responded to fish cues by increasing the use of refuges relative to controls, whereas Bufo, did not show any significant behavioural response to fish cues. In accordance with these observations, the proportion of Rana in refuges at the end of the experiment was high in the presence of fish cues, whereas the use of refuges by Bufo was not affected by fish cues. Predatory crayfish and fish chemical cues had effects on tadpole survival, growth and refuge use.

Tadpoles in all treatments reduced periphyton biomass. Both crayfish and fish cues had positive indirect effects on periphyton biomass. The positive indirect effect of fish cues on periphyton was likely an effect of reduced grazing from Rana. Thus lethal, as well as non-lethal, predator effects on prey populations can influence lower trophic levels. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Oikos
volume
88
issue
1
pages
181 - 190
publisher
Wiley-Blackwell
external identifiers
  • scopus:0343550379
ISSN
1600-0706
DOI
10.1034/j.1600-0706.2000.880120.x
language
English
LU publication?
yes
id
f20683f2-fd49-4d3b-8abc-3c26cef188f7 (old id 149791)
date added to LUP
2007-06-28 15:51:41
date last changed
2017-02-19 03:26:37
@article{f20683f2-fd49-4d3b-8abc-3c26cef188f7,
  abstract     = {We studied the effects of predatory crayfish (Pacifastacus leniusculus), the non-lethal effects of fish chemical cues (Oncorhynchus mykiss), and the combined effects of crayfish and fish chemical cues on the performance of tadpoles of two co-existing anuran species, Rana temporaria and Bufo bufo, in experimental pools. We also examined grazing effects on periphyton, the main food source for the tadpoles. Crayfish significantly reduced tadpole survival, particularly by feeding on Bufo. Rana benefited from reduced numbers of competitors, resulting from crayfish predation, by increased growth rate, whereas the growth rate of Bufo was unaffected by crayfish. The proportion of Rana in refuges (in relation to the number of survivors at the end of the experiment) was unaffected by crayfish, whereas proportionally more Bufo stayed in refuges in the presence of crayfish, relative to controls. Fish cues had no effect on tadpole survival of either species. During the entire larval period, Rana responded to fish cues by increasing the use of refuges relative to controls, whereas Bufo, did not show any significant behavioural response to fish cues. In accordance with these observations, the proportion of Rana in refuges at the end of the experiment was high in the presence of fish cues, whereas the use of refuges by Bufo was not affected by fish cues. Predatory crayfish and fish chemical cues had effects on tadpole survival, growth and refuge use. <br/><br>
Tadpoles in all treatments reduced periphyton biomass. Both crayfish and fish cues had positive indirect effects on periphyton biomass. The positive indirect effect of fish cues on periphyton was likely an effect of reduced grazing from Rana. Thus lethal, as well as non-lethal, predator effects on prey populations can influence lower trophic levels.},
  author       = {Nyström, Per and Åbjörnsson, Kajsa},
  issn         = {1600-0706},
  language     = {eng},
  number       = {1},
  pages        = {181--190},
  publisher    = {Wiley-Blackwell},
  series       = {Oikos},
  title        = {Effects of fish chemical cues on the interactions between tadpoles and crayfish},
  url          = {http://dx.doi.org/10.1034/j.1600-0706.2000.880120.x},
  volume       = {88},
  year         = {2000},
}