Danionella cerebrum: Like a gunshot — is this tiny transparent fish world's loudest?

Berlin scientists have discovered a small transparent fish can produce sound comparable to that of a firecracker or a jackhammer.

They were inspired to look into it after they heard unexplained clicking sounds originating from their lab's fish tanks, according to BBC.

They discovered that the fish, Danionella cerebrum, uses an organ known as a swim bladder to produce a strong beat.

It sounds like a gunshot, tapping out at 140 dB in the waters near the fish.

The species, which is 12 mm long, is thought to be the loudest fish for its size that has been discovered.

They think that drumming could be a way for people to communicate socially.

The larger the animal, the louder the noise in most of nature's domains.

However, it's a different situation underwater, where the little species is currently among the noisiest that have been found.

Scientists have discovered that some animals, including the appropriately named pistol shrimp, are capable of producing sounds as high as 200 dB when hunting other species.

Science values Danionella because its openness allows researchers to closely investigate its behaviour and observe its brain in action.

However, the scientists in their German lab observed something strange when they were working with these fish.

"People were just walking past the fish tanks, and they could hear these sounds, and were wondering where they were coming from," said Verity Cook, the lead author of the study, and a PhD Student at Charité University, Berlin.