River and wetland habitat

Rivers and wetlands control how surface water moves through the Rouge Watershed. These habitats occupy a relatively small portion of the total park area, but provide important ecosystem services and habitat for plants and wildlife.

Rivers and streams run throughout Rouge National Urban Park and their characteristics vary significantly. As you travel from the northern headwaters of the Rouge Watershed to the mouth of the Rouge River, stream channels generally become wider and deeper and water temperature increases. Different species also occupy these different habitats. The upper portion of the watershed is home to more cold water and cool water fish species, while the lower reaches support warm water fish species. Migratory lake species such as rainbow trout, brown trout and chinook salmon travel throughout the watershed from Lake Ontario to upstream areas to spawn.

Rivers and streams also provide habitat for many invertebrate species. For example, juvenile insects often spend their lives in stream bottoms until they are ready to complete their metamorphosis into adults. The plant-rich areas beside streams (known as riparian zones) are also very important to park ecosystems. These strips of grass, shrubs, and trees help to reduce soil erosion, filter contaminants and excess sediment, and provide shade, which keeps water temperatures cool enough for cold water fish species to survive.

Wetlands are another type of aquatic habitat within the Rouge and are defined as low-lying areas covered by water (year-round or seasonally), that support aquatic plants and wildlife. They can be recharged by groundwater, precipitation or a combination of both. Wetlands are highly diverse and productive areas and provide crucial habitat for many species of turtles and frogs. Waterfowl such as black ducks, mallards and wood ducks also use wetland areas for foraging, nesting and raising their young.

In addition to creating habitat for wildlife, wetlands provide other important ecosystem services that contribute to the overall health of the Rouge Watershed.

• Store and purify water
• Reduce the downstream transport of eroded sediments and excess nutrients
• filter contaminants
• recharge groundwater
• reduce the chances of flooding

They also help to regulate local climates, promoting cooler temperatures in the summer and warmer temperatures in the winter.

Wetlands can be found throughout the park—check out the restored Beare Wetlands while hiking the Cedar Trail or visit Rouge Marsh to explore the largest and best remaining coastal wetlands in Toronto.