Changes in the feeding behavior of the deposit feeder polychaete Laeonereis acuta on soft sediments inhabited by burrowing crabs.

PALOMO M. G.; MARTINETTO P.,; IRIBARNE, O.

MARINE BIOLOGY

SPRINGER

Año: 2004 vol. 145 p. 657 - 667

0025-3162

In this paper, we evaluate the influence of theburrowing crab Chasmagnathus granulatus on the feedingbehavior, body condition, burrowing activity, andfecal production of the deposit-feeding polychaete Laeonereisacuta. Previous results and ours show that, dueto crab activity, sediment organic matter decreases withdepth outside a crab bed, but there were no differencesinside. Also, particle sizes were smaller inside the crabbed. Polychaetes showed better body condition insidethe crab bed, suggesting higher energy gain. They fed onthe surface more frequently outside the crab bed thaninside. However, feeding rate was higher inside the crabbed, which is consistent with the larger weight and volumeof fecal pellets found inside crab bed. In both areas,the bedload sediment transport was not similar to thesediment ingested by this polychaete. A 1-month exclusion/inclusion experiment performed outside and insidethe crab bed showed that the body condition of polychaeteschanged between areas but that this was notdirectly due to crab manipulation. Thus, our resultssuggest that the higher sediment quality inside a crabbed can positively affect the feeding behavior of thedeposit-feeding polychaete L. acuta, increasing itsfeeding rate and consequently enhancing its bodycondition.