A Black Reef Leatherjacket, Eubalichthys bucephalus, at Jervis Bay.
Flicking the dorsal fin spine back and forwards is usually a sign of aggression. Most likely the two fish in the movie are both males. Thank you to Dr Barry Hutchins for his comments on this behaviour.
Last Updated: 3 December 2014
Black Reef Leatherjacket,
Black Reef Leatherjacket at Jervis Bay View full size
Photographer: Sascha Schulz © Sascha Schulz
Black Reef Leatherjackets at Shark Point View full size
Photographer: Ákos Lumnitzer © Ákos Lumnitzer
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