Question
We have a well established concrete pond 14' kidney shaped pond 3' deep with many rocks for goldfish to go under. Last year a frog appeared to take up residence, and has returned this spring. We are in coastal B.C. We have seen blue herons 'fishing' in our pond but wonder if a frog, less than fist size would be eating our gold fish? Most of the fish are a few years old so about 3+ inches long. Thanks for your answer.  

Answer
A fist-sized frog could eat a 3" goldfish, especially if it's a bullfrog.  That said, my frogs of similar size have never shown any desire to eat fish.  I think since you have the herons in the area, if you're losing goldfish to predation, it's more likely due to the herons.  Bullfrogs certainly will eat fish though.

Robyn
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