An curved arrow pointing right. Fish maw — the swim bladder of a fish — is one of the most expensive dried-seafood products in the world. A Chinese delicacy, it can fetch $450 to $1,000 per ...

The footage, captured in Spain's Canary Islands, shows the female fish, whose Latin name translates to "black sea monster," swimming through the light-filled ocean waters off the coast of Tenerife.