If you've ever thought about setting a pet goldfish free in a local pond instead of flushing it, Alberta's government has a message for you: please don't. A goldfish recently pulled from a stormwater pond in Okotoks made the rounds for its size alone — 30 centimetres long, 2.4 pounds, roughly the size of a dinner plate. But behind the eye-catching photo is a problem showing up in ponds and waterways across the province.

Goldfish are one of Alberta's most disruptive invasive species once they're loose in the wild. What starts as one unwanted pet can turn into a serious infestation fast — a single released goldfish can produce an estimated 40,000 offspring within three years, breeding up to three times a year. From there, they crowd out native fish for food, damage aquatic plants, and drag down water quality as their numbers grow.

The tricky part is there's no simple fix once they've settled in. Because there's no way to remove just the goldfish without affecting every other fish in that pond or lake, the province says prevention really is the only reliable solution. That's the thinking behind its "Don't Let It Loose" campaign, which reminds Albertans never to release aquarium pets, water garden plants, live bait, or extra sportfish into local rivers, lakes, ponds, or storm drains.

"Goldfish belong in aquariums, not in Alberta's waters," said Grant Hunter, Minister of Environment and Protected Areas. "Don't let it loose. Report sightings of invasive fish and help protect Alberta's ecosystems by following the law."

There's also a public health angle: fish that are dumped, dead or alive, can carry diseases and parasites into local ecosystems. And moving live fish between waterbodies is against the law in Alberta, with penalties reaching up to $100,000 and/or a year in prison.

If you spot a goldfish or other invasive fish while out at the lake or the local pond, the province is asking residents to call the Aquatic Invasive Species Hotline at 1-855-336-BOAT (2628), ideally with a clear photo of the fish's body and fins. Anyone who suspects a fish was released on purpose can also reach the 24/7 Report A Poacher hotline at 1-800-642-3800.