Thousands of Goldfish Taking over a Colorado Lake
An Environmental Article from

April 2015

[NOTE from Yet one more example of damage to our environment and harm/death to animals when we act as if it is all right to treat animals are commodities to be used/abused however we choose...]

goldfish damage
Photo attribution: Colorado Parks and Wildlife

As beautiful as it may seem to watch thousands of goldfish swim about in late afternoon light of a Boulder, Colorado day, for the Parks and Wildlife, it's a huge headache.

The exotic species, which were first noted by Boulder Open Space Rangers March 13, are now present in the thousands and will likely need to be removed to maintain the integrity of the lake.

"Goldfish are not a native species and are very harmful to the local aquatic ecosystem," said Kristin Cannon, district wildlife manager for Boulder. "We strongly encourage the public not to dump their unwanted pet fish in our waters. It is bad for our environment as well as illegal."

This is a big problem, as any non-native species in an area can knock out the balance of a sensitive ecosystem. Goldfish are not the only issue:

Also of concern is the "bucket brigade"-- anglers who choose to dump sport fish of their choosing into Colorado waters. While some nonnative fish are stocked at times, aquatic biologists only do so after a rigorous biological assessment to determine what can be stocked and where for a balanced ecosystem.

Teller Lake goldfish
Teller Lake - "the largest koi pond in these here parts"

The fish were most likely released into Teller Lake a few years ago. Goldfish can grow to a pretty large size unchecked. Removing them can be a huge headache as well:

Wildlife officials say they have two options: They can drain the lake and start rebuilding the natural fish stock from scratch, or they can bring in a specialized boat that would allow them to pick out the goldfish only.

A date has not been set for goldfish removal.

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