by 2022 Watershed Stewardship Assistant, Shannon Hart

Have you got any invasive species? Go Fish! If you have walked around a stormwater pond in Lethbridge, you may have seen a flashy little fish swimming about. Goldfish are a fun and easy pet that bring joy to many people, but what happens when they can no longer be cared for? An inventory of invasive species was done in Lethbridge in fall 2021; both goldfish and koi were found in three stormwater ponds. The City of Lethbridge is working with partners to remove these invasive species from our local water systems - and you can help! Come out to Firelight Pond on Saturday, August 13, 2022 for the Goldfish Derby. The derby will be held from 10 am to 4 pm with the goal of raising awareness about the issues of invasive species within our local water bodies. Community members are encouraged to participate by helping to capture goldish in Firelight Pond; a fishing license is required to remove the fish with a fishing rod. There will also be public education materials, family friendly activities, and food trucks on site, so there will be something for everyone. Before attending, you may wonder, what’s the big deal - why can’t these fish stay in our local water bodies?

All that Glitters

What is a goldfish (Carassius auratus)? The goldfish is a freshwater carp species that is native to East Asia and has become a popular indoor aquarium pet. Goldfish were selectively bred for colour in China more than 1,000 years ago and can vary in size, body shape, and colouration! When in a small fish tank, goldfish rarely grow larger than 5.1 cm (2 inches) long but in outdoor water bodies, they can grow to about 36 cm (14 inches) long. Goldfish are opportunistic feeders, meaning that they do not stop eating as long as there is available food. When they consume excess food, more waste is produced, which can impact their habitat. Goldfish are a highly adaptable species and can survive in both high- and low-quality habitat conditions, such as temperature fluctuations, pH changes, pollution, and low oxygen. Unfortunately, all these qualities make the goldfish an ideal candidate for being considered an aquatic invasive species.

*Goldfish will keep growing as long as there is available food and habitat! Photo by Shannon Frank, taken October 2020 in Lethbridge.*

Unwelcome Guests

There’s an old saying that guests, like fish, start to stink after three days; this rings particularly true with regards to undesirable pests like goldfish and other aquatic invasive species (AIS). An AIS is a non-native, undesirable species that causes ecological or economical harm to the ecosystem that it is introduced to. These can take the form of fish, invertebrates, or plant species, who are existing outside of their natural range. These species can quickly populate an area as they don’t have any natural predators in their new home, so they can outcompete and harm native populations. This can result in changes within habitats that are potentially detrimental; diseases, bacteria, and parasites can also be introduced, causing harm to sensitive ecosystems and species at risk. Invasive species can arrive by land, air, or water, intentionally or unintentionally. AIS can also harm recreational activities such as swimming, boating, and fishing through damage to infrastructure, unsuitable water conditions, and harm caused to native species.

“Aquatic invasive species are fish, invertebrate or plant species that have been introduced into a new aquatic environment, outside of their natural range.... They can outcompete and harm native species. They can even alter habitats to make them inhospitable for the native species.”

— Fisheries and Oceans Canada

When Goldfish Become Ghoulish

Know anyone who has given their expired goldfish a beautiful funeral, ending the heartfelt service by flushing it down the toilet? Both intentional and unintentional releases of aquatic invasive species like goldfish may occur because of pond and aquarium owners disposing of fish, plants, and invertebrates incorrectly. Owners have a responsibility to take care of the species in their charge and ensure that the artificial environment stays separated from the outside environment. They are also required to dispose of species in their possession in a safe and humane manner. Most fish, if not already dead, are killed by the shock of cold toilet water and chemicals used to treat water; a few, however, do end up surviving the harrowing journey and may end up in a local water body because of it. Other problems may include pipe blockages and/or the remains of your pet carrying diseases into new environments, harming native biodiversity.

Don’t Let It Loose

The release of live fish into water bodies within Alberta is illegal and can result in fines of up to $100,000. Putting local fisheries at risk creates problems for the native fish communities, their ecosystems, and the public who enjoy these areas. The Don’t Let It Loose campaign aims to inform Albertans on the concerns surrounding the release of AIS into local water bodies.

If you detect an AIS, you are required to report it under the Fisheries Act of Alberta. This Act regulates 52 aquatic invasive species deemed to be damaging to Alberta’s environment. Reports that occur within 14 days are the most effective in helping to minimize the spread and impacts of these species on local ecosystems. There are three methods to report AIS:

AIS Hotline 1-855-336-BOAT
EDDMaps Alberta App or online
Email aep.ais@gov.ab.ca

There are maps available to track invasive species. If these populations do occur, the Alberta Government and several other partners help to support organizations and municipalities’ response treatments by guiding the approval process and supporting the development of these plans. The following options may be utilized to eradicate invasive species:

Netting or electrofishing to physically remove the AIS,
Chemical methods,
Water table fluctuations

Nothing Gold Can Stay

While they may be small, goldfish and other AIS are mighty in numbers; they may cause damage to the local environment, outcompete native species populations, and cost a lot to eradicate them and deal with their impacts. Diseases may be spread, and blockages can occur within our water systems. To protect and maintain Alberta’s water systems, goldfish and other non-native species must be cared for - and eventually disposed of - responsibly to avoid further action. Some pet stores may take in unwanted live fish. For deceased fish, approved disposal methods include cremation, waste disposal, and backyard burial. The Alberta Invasive Species Council provides biodegradable fish pods for anyone who wishes to bury their fish in their backyard in a sanitary and safe manner.

Everyone is welcome to attend the Goldfish Derby, it is a fun event with great opportunities to learn about the impacts of AIS and what you can do to help mitigate them. Grab your fishing rod and come join us at Firelight Pond, 64 Firelight Way West, Lethbridge, to participate in this community experience. Here’s hoping this upcoming fishing derby goes swimmingly!