Set up of a vital marking method in european sturgeon larvae

• Main Authors: Lochet, Aude, Jatteau, Philippe
• Other Authors: Ecosystèmes estuariens et poissons migrateurs amphihalins (UR EPBX), Centre national du machinisme agricole, du génie rural, des eaux et forêts (CEMAGREF), irstea
• Format: Report
• Language: French
• Published: HAL CCSD 2010
• Subjects: [SDE]Environmental Sciences; Acipenser baerii; Siberian sturgeon
• Online Access: https://hal.inrae.fr/hal-02596677; https://hal.inrae.fr/hal-02596677/document; https://hal.inrae.fr/hal-02596677/file/pub00034716.pdf

Since 2007, more than 130,000 young European sturgeons were marked and released in the Garonne and the Dordogne rivers. Marking success in 2007 and 2008 was very limited: six months after immersion into a tetracycline hydrochloride bath (300ppm-8h), only 50% of the fish were marked. Consequently, our marking protocol had to be improved. New concentrations and new markers were tested using, first, our biological model Siberian sturgeon Acipenser baerii. The marking protocol with tetracycline (600ppm-8h) was used to mark the 33,100 European sturgeons released in the rivers in 2009. However, the alizarin red S marking trials were not successful on European sturgeons. Adjustements are needed before using this molecule for mass markings. The experiments on Siberian sturgeons also showed that, despite all our efforts, marking success remains relatively low. Considering the most efficient marking protocols, marking success do not exceed 70%, only one month after marking. Pectoral fin ray is the preferred sampled structures on sturgeons. It is the one we used to detect chemical marks. However, a comparative study of mark quality between different structures (pectoral fin rays, otoliths, dorsal scutes) showed that pectoral fin ray is not a reliable structure to check on chemical marks. Further investigations are needed to find calcified structures suitable for chemical mark detection. Depuis l’année 2007, plus de 130 000 jeunes esturgeons européens ont été marqués puis relâchés en Garonne et en Dordogne. Pourtant, l’efficacité des marquages réalisés en 2007 et 2008 s’avère très limitée : 6 mois après la balnéation dans du chlorhydrate de tétracycline à 300ppm pendant 8h, seulement 50% des individus présentent une marque. Pour améliorer le succès au marquage, de nouvelles concentrations en marqueurs et de nouvelles molécules ont été testées. Dans un premier temps, les expérimentations ont été réalisées sur un modèle biologique l’esturgeon sibérien Acipenser baerii. Ainsi, le protocole de marquage à la tétracycline à ...