ISSN:
1573-5133
Keywords:
Fish diets
;
Fish feeding
;
Diel feeding
;
Characidae
;
Serrasalminae
;
Serrasalmus
;
South American fish
;
Tropical fish
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Synopsis During the 1988 rainy season, I studied the 24 h feeding chronology of juvenile (40–68 mm standard length) piranhas, Pygocentrus notatus (Characidae: Serrasalminae) from a natural population inhabiting a small savanna stream in Apure State, Venezuela. Stomach contents analyses, supported by laboratory determinations of digestion rate, showed that these fish are primarily diurnal carnivores. Predatory activity on 4–5 August 1988 increased markedly after sunrise, peaked around 1100 h, and essentially stopped after sunset. Means of stomach content weight-to-fish weight ratios among the periods sampled were significantly different. Small fish were the major prey at all hours (81% of total prey volume). Underlying factors responsible for the observed 24 h feeding patterns were not investigated, but avoidance of predation by adult piranhas, which were very active near sunset, may have been important.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00000568
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