A goldfish sighting in the Drake Landing storm pond over the weekend may have some residents concerned the treatments last year weren't effective or people are dumping their fish again.

The Town of Okotoks had both the Drake Landing and Crystal Ridge storm ponds treated with rotenone last year to eradicate an overwhelming population of goldfish that had been illegally dumped in them.

Christa Michailuck, parks manager for the Town of Okotoks, says she doesn't believe the fish spotted a few days ago was released into the pond by a resident.

"With goldfish in particular they don't grow to be large over night, it takes them several years to get to that size, so if a large fish was seen coming out of that pond just this past weekend it's probably at least five years old so it either was missed in the second treatment somehow or came in from one of the upstream ponds through the pipe system."

The ponds upstream of the Drake Landing storm pond are the Beatrice Windham pond and two storm ponds in the Air Ranch community. Those ponds are monitored by the Town for fish activity.

According to Michailuck the rotenone treatments were highly effective and notes the larger fish were more resistant to the treatments with about 10,000 smaller fish succumbing to the first round and 30 larger fish taking to the second.

Soon a new test will be available for goldfish.

"A water sample can be taken and the fish can be tested forward genetically through DNA in the water to be more accurate so you know if there's fish present or not without actually seeing them so that will really help to monitor the problem going forward," says Michailuck.

The Town is reminding residents of the harmful impacts releasing an invasive species can have on the ecosystem and that it's financially a costly issue where huge fines can be given if caught.

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