Food and feeding behavior of the guppy, Poecilia reticulata (Pisces: Poeciliidae)

Abstract

Digestive tracts of wild guppies, Poecilia reticulata (Pisces: Poeciliidae), contained mainly benthic algae and aquatic insect larvae. In the laboratory, guppies matured on diets consisting solely of Chlorococcum (Chlorophyceae), but growth rates were slower than those of fish raised on Daphnia or commercial dried food. Fish grazing benthic algae performed rapid pecks in which the jaws were maximally protracted to cover a relatively large area. Pecks were performed in series at mean intervals of 0.55 s. Jaw movements required 0.17 s, while substrate contact lasted 0.03 s. Ingestion per peck increased with fish size and algal density. Males fed at lower food densities and ingested more per peck than females of similar weight. Females had longer feeding bouts than males. The fish ingested 16–25% of their body weight in dry weight of algae daily when they were fed ad libitum.