405_April_24

MARINE BIOLOGY WITH MIKE SCOTLAND - FISH IDENTIFICATION

Dusky leatherjackets show strong pair bonding. Male and female are identical.

You can gain an insight into how tough their lifestyle is when you see them snacking on a piece of sponge or a Jelly blubber. Their diet is spartan and low in nutrients. However, that is true for many fish especially in the tropics. After all, many tropical fish are rock munchers, rock biters or sand swallowers. Ask any Hawksbill turtle or Leatherjacket if they would like to snack on a pair of your old leather boots. This would be a real delicacy compared to the usual fare that they survive on. Of course, they would have no trouble with hard leather as they are used to crunching up the

extremely tough Tunicates, chunks of sponge and seaweed. Leatherjackets have a small mouth at the tip of their large head. It is filled with a gruesome set of large sharp teeth. They can easily cut through fishing line and even tracer wire. They have strong teeth and can inflict a painful bite, I am told. Their eyes are unusually high up on the head and they have a small gill opening and no gill cover or operculum. Many leatherjackets have strong spines on the side tail area known as the caudal peduncle. The Yellow Fin

The Scribbled leatherjacket from Menjanggan Island in NW Bali

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DIVE LOG Australasia #405 - April ‘24

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