Fish using tools: Can fish use tools? These three fish found in the Laccadive Sea use tools

Three fish species have been found of being using tools in the Laccadive Sea. The checkerboard wrasse and the Jansen wrasse have not been seen making use of tools before. However, this has been proven to be possible with the case of moon wrasse making use of tools in the wild. All the three species made use of dead or living coral structures as anvils. They use these as tools to crack the hard shells of the sea urchins. Cracking these shells makes way for these species to get inside the edible bits inside.

Do fish need tools? If yes, what for?

The E.molaris is a sea urchin. Like many of the urchins, these are covered in a specific armour of spines. It holds a hard skeleton that sheilds the internal organs of the E. molaris, making it quite troublesome for the fish with the unspecialized parts of the mouth to prey on.

Various wrasse species make use of substances surrounding them. These substances are used as makeshift tooks to crack the urchin tests. Accessing the prey inside these shells thus becomes easier.

The use of tools

The archer fish has specialized mouthparts, but the three wrasses did not have these mouthparts. They made use of a set of specialized behaviors in order to take the challenges of preying on the sea urchins.

When a wrasse encounters with a sea urchin, it carefully comes near it from the side and make use of its snout to turn the urchin over. This exposes the underside with soft spines.

Then, the wrasse would pick up the urchin that was overturn in the jaws. It draws immense benefits of the lesser number of spines.

The wrasse then swims to the nearest hard coral with the urchin in the mouth. The wrasse then strikes the urchin against the coral incessantly.  Once the urchin's test opens up, the wrasse accesses it and eats the delicate internal parts.