By Kevin Ma
Owen Watkins is up to his elbows in the muck of Edgewater Pond. Dragging a long seine net behind him, he’s on the hunt for aliens.
“See there on the right corner?” he said earlier, standing on the pond’s dock. He points to two fiery gold blobs milling about in the brown murk below the swarm of damselflies.
They’re goldfish – one of the many invasive aquatic creatures that shouldn’t be in Alberta waters.
Residents and city officials alerted Alberta Environment to the presence of the invasive fish earlier this month. Watkins came out to the pond this week to capture some of the fish for study.
“I can see them scooting around me,” he says, as he carefully wades through the muddy waters while towing his end of the net.
After one sweep of one corner of the pond, he drags the net ashore. There are at least 35 medium-sized goldfish in it, plus scores of thumbnail-sized baby ones.
Watkins says he saw hundreds of these fish last week as he walked the pond’s perimeter. There was even a kid fly-fishing for them.
City environment manager Mike Mellross says he’s seen whoppers half the length of his arm in this pond, and that he’s now working with Watkins to find out how to get rid of them.
“Operationally, we don’t want goldfish here.”
What’s wrong with goldfish?
Aquatic invasive species didn’t receive a lot of attention in Alberta up until a few years ago, says Kate Wilson, Alberta Fish and Wildlife’s aquatic invasive species specialist.
Prior to a few months ago, just two were listed as banned under the province’s Fisheries Act. That changed to about 52 just before the last provincial election was announced when some revisions to the act kicked in. Of those 52, 16 are plants (many of which are already listed under the Weed Control Act), 11 are bugs or shellfish, and 25 are fish.
One of those fish, the bullhead catfish, made headlines last month when Alberta Environment discovered that the Texaco East pond near Fort McMurray had been illegally stocked with them. (The pond has been closed as a result.)
Another, the snakehead, can be found in a big tank at St. Albert’s Paradise Pets. Dubbed “Kane,” it’s a two-foot long grey monster, and it’s not for sale.
Snakeheads likely made the banned list because they’re very big and aggressive, says store general manager Adrian Theroux, who took on Kane as a charity case.
“We can’t put any other species of animal in the enclosure with it,” he says, as these fish will eat everything from crayfish to birds.
Due to the change in the law, Theroux says he now has one year to find someone who’s willing to adopt this fish – he suspects he’ll have to euthanize it instead.
While goldfish are definitely not native to Alberta and are invasive, they aren’t one of the 25 fish listed in the act, as listing them would require the province to ban their sale and possession, Wilson says.
Koi and goldfish will eat anything that fits in their mouth and can have significant impacts on native frog, fish and insect populations, says Theroux, when asked why they shouldn’t be released into the wild. They can also introduce new diseases to water bodies.
Goldfish poop can also encourage algal blooms and eutrophication, or the excessive addition of nutrients to water, Watkins says. The long lives, hardiness and high reproductive rates of goldfish all mean that they can easily crowd out native species.
“A few fish makes a lot.”
City officials have known since at least 1999 that there were koi and goldfish in the Lacombe Lake stormwater pond, the Gazette’s archives suggest.
Edgewater Pond was built in 2011 and had goldfish added to it sometime after that, Mellross says – probably within the last three years, as it would have been inspected for fish in 2012 prior to being turned over to the city.
Watkins suspects the fish got into these ponds when pet owners emptied their aquariums into them.
Wilson says she’s been getting reports of goldfish in water bodies in every urban area from Lethbridge to Fort McMurray.
“That’s quite shocking,” she says.
“If goldfish are surviving in stormwater ponds in Fort McMurray, a lot of other things we know are far more dangerous could also survive (there).”
Goldfish are now so widespread that the province is struggling to figure out what to do about them, Wilson says. They’ve launched a provincial “Don’t Let It Loose” campaign this summer to discourage people from releasing or flushing these and other aquarium fish.
If you catch a goldfish or any other banned fish, Wilson says you should kill it immediately and not transfer it to another water body. Trafficking a banned fish can lead to a $100,000 fine and possible jail time.
Dead goldfish or invasive fish should be buried or put in the trash, she continues – flushing them can spread pathogens into the water.
Unwanted fish can usually be given back to the pet-store or sent to the Aquarium Club of Edmonton, Theroux says.
Watkins says he plans to study the fish he collected from Edgewater Pond to determine their age and sex ratios. The varied sizes he caught this week show that the goldfish are definitely reproducing in the pond, and may have gone through a few generations.
While Lacombe Lake is not connected to the Sturgeon River, Edgewater Pond is, Mellross says. However, there’s also a lift station full of grates between it and the Sturgeon, making it all but impossible that the fish could escape into the river.
Anyone who spots an invasive fish in Alberta should report it by calling 1-855-336-BOAT (2628).