Genetic identification of fish caught as by-catch in the Antarctic krill fishery and comparison with observer records

• Main Authors: Polanowski, A, Clark, J, Maschette, D, Welsford, D, Deagle, B
• Format: Conference Object
• Language: English
• Published: CCAMLR 2018
• Subjects: Agricultural; Veterinary and Food Sciences; Fisheries sciences; Fisheries management; Antarctic; The Antarctic; Antarc*; Antarctic Krill; Icefish
• Online Access: https://www.ccamlr.org/en/wg-emm-18/30; http://ecite.utas.edu.au/137154

Juvenile/larval fish taken as bycatch in the Antarctic krill fishery (CCAMLR subarea 48.1, 48.2 and 48.3) were identified by DNA barcoding and results compared with morphological identifications made on vessels by scientific observers. A total of 344 fish (primarily in the families Channichthyidae and Notothenidae) were identified using genetic barcoding markers. Species level identifications provided by observers were good for the common species Champsocephalus gunnari and Lepidonotothen larseni however, DNA results show several less common Notothenidae species were identified as L. larseni . All of Chaenodraco wilsoni icefish (n=67) identified by an observer were actually Chionodraco rastrospinosus based on DNA barcoding. Many of the specimens (n=136) were recorded to family-level by observers; genetic barcoding markers allowed these specimens to be assigned to species level. The diversity of fish identified by observers (5 families; 8 species) was considerably lower than with DNA barcoding (7 families; 20 species). The impact of potential taxonomic misidentifications on fish bycatch datasets needs to be considered. Developing standardised field guides and additional observer training many improve the accuracy of observer taxonomic assignments.