What eats Great Diving Beetles?

Question

What eats Great Diving Beetles?

Answer 1

The larvae (aka "water tigers") are very cannibalistic and will feed on each other if possible. They are small and decent swimmers but I imagine that many a fish/or larger aquatic insect gets in a meal on them.

The adult beetles are preyed upon by birds and mammals. It appears their biggest predator is Humans! Eaten in Mexico, Japan and China. Also reportedly eaten in Taiwan, New Guinea and Thailand. It's well known that insects are an excellent untapped source of protein. Although most folks in the U.S. wouldn't dream of eating on these beetles, they are bred as a food source in other countries. Cool! :)

Answer 2

Fish.