Growth, mortality and yield of the mudprawn Upogebia pusilla (Petagna, 1792) (Crustacea: Decapoda: Gebiidea) from western Greece

The paper presents data on growth, mortality and yield of the mud prawn Upogebia pusilla in western Greece. The species is intensively exploited in the area as live bait for hand lines and long lines both for professional and sport fishermen. The study area is a closed bay in western Greece with a small opening which connects it to the Ionian Sea. Longevity of the species in the study area was found to be 4+ years. Females' total length ranged between 18 and 54 mm; for males it ranged between 16 and 58 mm. The von Bertalanffy parameters for males were L-infinity=60.30 mm, K=0.520 per year and t(0)=-0.0166 years; for females they were L-infinity=58.80 mm, K=0.621 per year and t(0)=-0.1261 years. Overall von Bertalanffy equation parameters were L-infinity=61.05 mm, K=0.521 per year and t(0)=0.086 years. Maximum weight was estimated as 3.440 g at L-infinity based on the length-weight relationship. Mortality estimates were Z=1.510 per year, M=0.928 per year and F=0.582 per year resulting in an exploitation ratio of E=39%. Using the above values, yield per recruit was estimated at 2.97 g/year at F-max levels of 0.750 per year and E-opt=50%. Overall length-weight relationship was estimated as: W = 0.01589TL(2.972), r(2) = 0.886. This paper contributes to the knowledge of population dynamics of the species Upogebia pusilla and in particular, growth, mortality and yield.