Sea Shorts: Fishing for Squid

This fishing boat is kitted out to catch squid. How can you tell? Check out the rows of lights hanging from the grey bar near the front (bow) of the boat! These fishing boats head out sea at night time and shine their bright lights. Squid then gather around the light in great numbers, making it easier for the fishers to catch their prey.

 Squid fishing boat in Hakodate, Hokkaido, Japan. Credit Samantha Andrews

Squid fishing boat in Hakodate, Hokkaido, Japan. Credit Samantha Andrews

So why are squid gathering around the lights in the first place?

Actually, we aren’t 100% sure. It might be an evolutionary response; they are attracted to the lights – rather like they would be to bioluminescent animals (which naturally emit their own light) that they would want to eat.

Or it might be because they lights show up their unsuspecting prey. Zooplankton (tiny marine animals) head to the surface to feed at night time. Under the cover of darkness, they are safer from the eyes of squid and other animals that want to eat them. Unfortunately for the zooplankton, the lights from the fishing boat make it easy for the squid to see them! Under this scenario, the squid aren’t attracted to the light as such – more to an easy meal.

Or it could be something else entirely different – isn’t nature wonderfully mysterious!