Effects of pectoral fin ray removal on Siberian sturgeon Acipenser baerii swimming performance

Fin ray biopsies are commonly used to age sturgeon, but the effects of fin ray biopsy on Siberian sturgeon Acipenser baerii swimming performance are unknown. Therefore, the effects of two fin ray biopsy methods on swimming performance of hatchery-reared, juvenile Siberian sturgeon were evaluated in this study. Treatment fish were subjected to one of two biopsy methods: removal of a 2- to 4-cm section from a marginal pectoral fin ray, or full removal of a marginal pectoral fin ray. Control fish were only subjected to a sham operation. A modified 2,936-l Brett-type swim tunnel was used to evaluate 10-min critical station-holding speeds (C (SHS)) and behavioral swimming characteristics of sturgeon immediately after fin ray biopsies were carried out. Fish sizes (range 65- to 84-cm fork length) were comparable among treatments. Mean 10-min C (SHS) (mean +/- SE) were 113 +/- 3.4, 109 +/- 2.5, and 111 +/- 2.8 cm s(-1) for the segment removal treatment, full removal treatment, and control treatment, respectively. ANOVA indicated that the two methods had no significant effect on the 10-min C (SHS) of Siberian sturgeon compared to the control treatment. Results indicate that fin ray removal has no effect on Siberian sturgeon swimming performance.