Blue Planet II: ‘Seeing a fish use a “tool” for the first time was remarkable”

Dive into the new Blue Planet II book accompanying the landmark BBC One series with an extract examining the impressive tuskfish

Diver and fish
Blue Planet II

Seeing a fish use a "tool" for the first time was truly remarkable

‘Seeing a fish use a “tool” for the first time was truly remarkable,’ adds Rachel. ‘Percy came back to his “castle” each day. He was a tenacious little thing, swimming for hours every day in search of clams that he would bash on his anvil for up to 20 minutes at a time.’

Tuskfish and shell

Piles of broken shells scattered around the coral head indicate that the tuskfish regularly uses the same ‘anvil’. Furthermore, similar collections of broken shells can be observed across the Great Barrier Reef, suggesting the behaviour may be widespread. Despite being a relatively conspicuous behaviour, anvil use in tuskfish had rarely been observed in Australia prior to commencement of filming Blue Planet II and has been professionally filmed for the first time by this series.

These resourceful tuskfish are in the wrasse family, and since these observations were reported several others have come to light. Off the Florida coast, the yellow-headed wrasse smashes scallops against an anvil rock, and in the Red Sea three species of wrasse collect sea urchins, drag them back to their territory, and break off the spines and split the test against a chosen rock to get at the soft parts inside. Fish are not noted generally for their intelligence, but digging up a clam or collecting a sea urchin, carrying it some distance in its mouth to a preferred anvil and then smashing it open, like a sea otter, requires some degree of forward thinking, and for a fish that’s a big deal.

Dive deeper into the world of Blue Planet II with the book that accompanies the landmark BBC One series. 

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