Posted by Stephanie Keener on April 21, 2005

Q: A friend recently told me that the release of goldfish in wild ponds and waterways destroys the native trout population (we live in the mountains of Western North Carolina). Could you tell me what kind of effect goldfish can have on a pond ecosystem and if they can breed with native trout?

A: Several thoughts go through my mind on this. I think it goes without saying that introducing exotic animals or plants into native waters is rarely a good idea. However, I don't think goldfish have been much, if any, of a problem in many of the areas they've been released.

First off, waters that are good for trout are NOT very good for goldfish. Trout fare best in cold, rather clear waters that are either moving as in streams, or deep in lakes. Goldfish, on the other hand, prefer quiet, warmer, shallower waters with lots of aquatic vegetation.

Many people think goldfish are just "gold carp" but they are a completely different species - they are related to, but definitely NOT, carp. Carp do muddy the waters by rooting in the bottom and can be a problem but goldfish do not.

Trout, especially larger ones, do not eat just insects but also feed on small fish. Young goldfish make excellent fare for many gamefish so do provide extra food in waters where they live.

No goldfish has ever bred with a trout - no problem there. These fish are too different for them to interbreed. Hope this answers your questions. Thanks for asking.

John Wiessinger ( April 22, 2005)