Estimation of Gut Throughput Time in Gammarus Pulex under Laboratory and Field Conditions with a Note on the Feeding of Young in the Brood Pouch

Abstract
A field method for measuring the minimum and mean throughput time of gut content of G. pulex using powdered charcoal applied as a food label to natural substrates is described. The possible effects of charcoal addition and gut mixing are considered. Preliminary results on mean gut throughput time of adult G. pulex were 119-160 min at 7.0.degree. C and 45-59 min at 13.8.degree. C. Young fed within the brood pouches of females.