Alberta has only a handful of invasive fish species, but they can still harm native fish and their habitats. Limiting the spread and importation of these species is critical to maintain the populations of the province’s native species and their aquatic ecosystems. Along with Prussian carp, goldfish, and oriental weather loach, the rosy red minnow is now another invasive species to watch for.
At first glance, the rosy red minnow may look like a harmless fish. It is small, brightly coloured, and relatively low on the food chain. Unlike many other invasive species, it doesn’t engage in burrowing, digging, or other water quality damaging behaviours. Despite its cheerful orange-pink exterior, the rosy red minnow’s competitive edge and resilience in Alberta’s waters stems from its origins as it is a domesticated breed of the native fathead minnow.
Rosy red minnows were bred in Arkansas in the 1980s, when their bright colouration appeared as a random mutation. This new breed of fathead minnow became popular as baitfish and aquarium fish, eventually leading to its introduction to Alberta waterways. So far, the rosy reds have only been found in 3 locations as of June 2026. The fact that they came from a native species means they are well adapted to local environmental conditions. The intense winter cold, low oxygen conditions, and other pressures which make Alberta resistant to most invasive species, has failed to stop these persistent minnows.
There is concern the introduced fish could alter local environments by competing with native fish and spreading disease. Aquarium fish are often much more diseased than their wild counterparts, and there is legitimate concern that the introduction of rosy red minnows could spread disease among multiple indigenous fish species. There is also concern that the rosy reds may be introduced to waterbodies where fathead minnows are not native. In such waterbodies, the alteration of the local ecosystem caused by their introduction is much more severe. There are already several invasive populations of rosy red minnows and fathead minnows established in B.C.
In addition to being well adapted to Alberta’s waterways, rosy reds are also prolific breeders. During the warmer months, females lay thousands of eggs while dedicated dads guard and fan the nests until the young hatch. Under ideal conditions, this allows their populations to balloon rapidly. Once established, their populations are extremely difficult to remove, and there aren’t viable ways to remove them without killing all fish present. Because of this, conservation strategies focus on prevention.
It is illegal to use live bait in Alberta, partially to limit the spread of invasive fish like the rosy red minnow. Additionally, it is extremely important that aquarium fish never be released into natural waterbodies. Instead, these fish should be returned to the store, given to new owners, or humanely euthanized.
By preventing the introduction of rosy red minnows, we can ensure that they do not become a competitive threat to our existing fish populations.
By Myles Grieve June 30, 2026
To learn more about rosy red minnows and what you can do, please visit our sources for this article:
Government of Alberta. (n.d.). Rosy red minnow. https://www.alberta.ca/rosy-red-minnow
Alberta Invasive Species Council. (2026, March). Rosy red minnow (Fact sheet, Version 2.1). https://abinvasives.ca/wp-content/uploads/2025/11/251118-FS-Rosy-Red-Minnow-V2-1.pdf
British Columbia Ministry of Water, Land and Resource Stewardship. (2024). Invasive species alert! Rosy red minnow (Pimephales promelas). https://www2.gov.bc.ca/assets/gov/environment/plants-animals-and-ecosystems/invasive-species/alerts/rosyredminnow_alert.pdf
To learn what to do with an unwanted fish, go here: https://abinvasives.ca/rehoming-aquarium-and-pond-network/