Blackstripe Topminnow

In the United States, it occupies parts of the southern drainage of lakes Erie and Michigan and also the Mississippi drainage basin between Illinois and the Gulf of Mexico. The entire Canadian population of this small freshwater fish lives along a roughly 60 kilometre stretch of the Sydenham River in southwestern Ontario, where its presence was discovered only in 1972. The blackstripe topminnow is a fairly hardy fish although its greatest threats come from changes to its habitat due to human activity.

Blackstripe topminnows have a lifespan of around two to three years. They are normally found in water with a slow current where there is vegetation along the river bank which provides a good amount of cover along the waters edge. They tend to stay near the surface in summer and feed on insects. They also eat insect larvae in the water, as well as tiny molluscs, spiders and crustaceans. In the winter, they retreat to deeper water. Spawning occurs between May and August. Females lay 20 to 30 eggs; these are fertilized and tucked away in underwater vegetation one at a time by the males.

Although this population in Canada seems to have remained stable in recent years, it faces several environmental risks. This species is dependent on both aquatic and marginal vegetation which is important as a source of insects for them to prey on. The blackstripe topminnow is also one of many species covered by the Sydenham River Recovery strategy. The Sydenham River Recovery Strategy, completed in 2003, was the first recovery strategy in Canada to use an ecosystem approach for aquatic species. The blackstripe topminnow is now being protected as part of a larger plan to return the Sydenham River's ecosystem to health.