Cootes Paradise - Fish

Fish

The wetlands function as a seasonal fish nursery for Lake Ontario, and despite the historical degradation, most historical species of fish can still be found using Cootes Paradise and in increasing numbers. As with birds and plants the location is the biodiversity hotspot for Canada with over 60 species present. Each spring thousands of spawning fish migrate in through the fishway from the harbour and lake, laying eggs and leaving shortly after, allowing the marsh to function as a giant fish hatchery. Annually between 5 and 20 million fish are produced for the lake depending on water levels and water pollution events. The species present reflect the degraded marsh habitat with the most common the Gizzard shad. Also common are night time predators species Channel Catfish and Brown bullhead, along with invasive species such as Alewife and White perch. Popular angling species present in limited numbers include pike, Largemouth bass, and Yellow perch, but the large adults are only present in the marsh during the spawning season which is closed to fishing. The spring and fall season also brings several migrating salmon and trout to the marshes main inflowing river.

In 2007, when there was low water level in Lake Ontario and a favourable wind, all the water was pushed out of Cootes Paradise and the remaining carp swam out into Hamilton Harbour. RBG staff removed the fish gates and herded out the last of the carp, and then replaced the gates. Since then the Paradise has been relatively carp free. In the absence of these large destructive bottom feeders there is a gradual return natural native plant species populations.