Gut evacuation rates in Nephrops norvegicus (L., 1758): laboratory and field estimates

Abstract

Estimates of gut evacuation rates of Nephrops norvegicus (Linnaeus, 1758) (Crustacea, Decapoda) were obtained during laboratory and field experiments. Individuals were collected off the south coast of Portugal in December 1997 and July 1998. Gut evacuation rates (R.h(-1)) were calculated from the slope of the regression of the natural logarithm of dry stomach content weight versus time, using data obtained by the "serial slaughter method". The values obtained during laboratory (R = 0.172 h(-1)) and field experiments (R = 0.177 h(-1)) are compared with gut evacuation rates reported for other marine organisms. The results obtained for both experiments are within the range of the values in the literature, even in the case in which different methodologies were used.