Blue Marlin pectoral fin - more 'laid back' than the Black :)

Ralph Foster uploaded this observation of a large marlin washed up on a beach in western South Australia.

We were initially unsure which species it was, so consulted billfish expert Julian Pepperell from Pepperell Research & Consulting. Julian stated, "This is almost certainly a blue marlin, Makaira nigricans." He made a number of excellent comments that can be viewed in the observation (click image, above). In particular he stated that, "The pectoral fin of the adult black marlin is permanently erect and locked in placed through fusion of the bones in the pectoral girdle."That immediately ruled out the fish being a Black Marlin. He also stated, "While it is not impossible for a black marlin to be stranded in that region, there have been numbers of very large blue marlin stranded on beaches from Albany to near Adelaide over the past several years, and historical records of this phenomenon going back to the 1980s at least, with photos showing them to be blue marlin." It's pleasing that Ralph's observation will add to Julian's data set and thus our knowledge of Australian billfishes.

Marlins are classified in the family Istiophoridae, which contains the Billfishes, Marlins, Sailfishes and Spearfishes. In Australia, the family contains five species, in five genera.

Thank you for your help Julian!