Hormonal manipulations of growth rate and its influence on predator avoidance - foraging trade-offs

dc.contributor.authorAbrahams, MV
dc.contributor.authorPratt, TC
dc.date.accessioned2007-10-09T15:50:17Z
dc.date.available2007-10-09T15:50:17Z
dc.date.issued2000-01-31
dc.description.abstractTheoretical investigations into the impact that predators exert on prey species suggest that two parameters, growth rate and mortality rate, should be the most influential in determining when animals should risk exposure to a predator in order to achieve higher feeding rates. While these two parameters have usually been assumed to be environmentally determined, we used thyroid hormone (3,3',5-triiodo-L-thyronine (T-3)) to manipulate growth rates and examine the behavioural consequences associated with these manipulations. In two experiments, we examined how the growth rate of fathead minnows (Pimephales promelas) is affected by treatment with T-3, and used the results from this experiment to make a priori predictions about their relative willingness to risk exposure to a predator in order to receive increased feeding rates. The first experiment demonstrated that T-3 significantly reduced the growth rates of fathead minnows compared with an unmanipulated control. When groups were compared in their relative willingness to risk exposure to a predator, manipulated growth rates in the first experiment were an accurate predictor of behaviour; groups with relatively high growth rates were more willing to risk exposure to a predator. These results are consistent with the theoretical expectation that growth rates should be an important factor determining decisions that involve trade-offs.en
dc.format.extent174659 bytes
dc.format.mimetypeapplication/pdf
dc.identifier.citationCAN J ZOOL, JAN 2000, vol. 78, no. 1, p.121 to 127.en
dc.identifier.doihttp://dx.doi.org/10.1139/z99-185
dc.identifier.urihttp://hdl.handle.net/1993/2910
dc.language.isoengen_US
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dc.rightsopen accessen_US
dc.statusPeer revieweden
dc.subjectIDEAL FREE DISTRIBUTIONen
dc.subjectFOOD AVAILABILITYen
dc.subjectRAINBOW-TROUTen
dc.subjectLIFE-HISTORYen
dc.subjectANTIPREDATOR BEHAVIORen
dc.subjectSPECIES INTERACTIONSen
dc.subjectAVOIDING PREDATIONen
dc.subjectSTEROID-HORMONESen
dc.subjectRISK-TAKINGen
dc.subjectSELECTIONen
dc.titleHormonal manipulations of growth rate and its influence on predator avoidance - foraging trade-offsen
dc.typejournal articleen_US
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