Biological Data Derived from Sturgeon (Acipenser stellatus, Acipenser gueldenstaedtii and Huso huso) by-Catch along the Coasts of the Southern Black Sea (Turkey)

Abstract

In this study, some basic bio-ecological features such as growth, reproduction and feeding of three sturgeon species (Acipenser stellatus, Acipenser gueldenstaedtii and Huso huso) are presented. The mean and range of total length were recorded as 57.3 (17.0-143.0) cm for A. stellatus, 58.9 (29.0-200.0) cm for A. gueldenstaedtii and 82.2 (33.0-359.0) cm for Huso huso. The mean and range of total weight were 2121.4 (42-16,000) g, 4073.8 (100-35,000) g and 49,090.4 (128-353,000) g for the three species, respectively. The value 'b', a basic parameter of the length-weight relationship was estimated as 2.09 for A. stellatus, 2.95 for A. gueldenstaedtii and 3.51 for Huso huso. Analysis of stomach contents revealed that the sturgeons fed mostly on benthic and benthopelagic macrofauna along the southeastern Black Sea. Catches in the rivers as well as gonad development of fish caught in the vicinity of the estuaries indicated remaining fish still enter Yesilirmak and Sakarya for spawning. The spawning migration especially in the Yesilirmak occurs mainly in the period from April to June.