The feeding response of the epibenthic amphipod Siphonoecetes dellavallei Stebbing to varying food particle sizes and concentrations

• Published in: Journal of experimental marine biology and ecology 1986, Vol.98 (1), p.51-63
• Main Author: Guidi, L.D.
• Format: Article
• Language: English
• Subjects: Amphipoda; Biological and medical sciences; Crustacea; feeding rhythm; food concentration; food particle size; Fundamental and applied biological sciences. Psychology; ingestion; Invertebrates; Marine; Physiology. Development; Siphonoecetesdellavallei
• ISSN: 0022-0981; 1879-1697
• DOI: 10.1016/0022-0981(86)90075-4

The feeding reponse of the surface deposit-feeding amphipod Siphonoecetes dellavallei Stebbing was studied by measuring the uptake of four different 14C-labelled foods (a pure culture of bacteria and three diatom species) lying on top of the sediment, as a function of incubation time. Both the particle size of the food and, to a lesser degree, food density affected feeding. When the foods were offered at the same concentration in terms of organic carbon (23 μg·cm −2), ingestion rate was positively related to particle size, and varied from 4.5 to 85 × 10 −4 μg organic carbon·μg individual dry wt −1·h −1.The relation between feeding rate and density of a given food was similar to that reported for planktonic suspension-feeders, i.e. a saturated feeding curve. In these conditions, the upper limit of ingestion rate appeared to be fixed by the maximal capacity of the gut. Feeding rhythm switched from continuous to intermittent feeding at relatively low densities of large food particles, and appeared to be determined by the time required to fill the gut. This study shows that although S. dellavallei is capable of ingesting a wide range of food particle sizes, only large enough particles are used efficiently and enable the animals to maximize the ingested energy while minimizing the time spent feeding.