Catfish hunts by detecting pH changes

A species of catfish locates its prey by sensing tiny changes in seawater pH.

John Caprio from Louisiana State University and colleagues identified small pH-sensitive sensors on the barbells (“whiskers”) of Japanese sea catfish (Plotosus japonicus).

They showed that the catfish use this sense to locate polychaetes, a primary food item, even in dark and murky water. Polychaetes respire tiny amounts of carbon dioxide and acid, which decrease the pH of the surrounding seawater.

Read more at Louisiana State University