REDSIDE DACE
HABITAT REHABILITATION
ABOUT REDSIDE DACE
The Redside Dace are an endangered fish native to Ontario. About 80% of their population range is within the Lake Ontario Watershed and the Greater Toronto Area. Due to rapid urban and agricultural development in this area, Redside Dace have suffered an extreme loss of critical habitat. Redside Dace play an essential role in ecosystems; as insectivores they help manage the populations of insects such as mosquitos. If Redside Dace populations continue to decline we may see an increase in mosquito populations - and no one likes mosquito bites!
The Redside Dace's native range has decreased significantly over the past few decades. They were once common throughout the Rouge and Humber River watersheds but are now limited to small stretches of stream in the upper headwaters.
Threats:
- Excessive sedimentation (check out the Silt Smart protocols for development sites)
- Loss of streamside vegetation
- Alteration of flows
- Increasing water temperatures
- Increased pollution
This minnow species has been listed as endangered provincially since 2009 and federally since 2018. Because of increasing awareness about this species at risk, Ontario Streams has performed and continues to lead restoration projects throughout the GTA targeting historical Redside Dace habitats. The hope is that by improving habitat through the planting of streamside shrubs, installation of in-stream habitat, litter cleanup, and installation of erosion control structures, remaining Redside Dace populations will be encouraged to return and spawn, improving the overall health and resilience of this species in the GTA.
To learn more about Redside Dace, check out our video series and infographics with the Toronto Zoo!
Check out our Redside Dace activity sheets!
We also have published a blog post with Ontario Nature about the sensitive Redside Dace and how we are helping!
HABITAT RESTORATION
Ontario Streams implements habitat enhancement structures to streams and riparian areas to improve the habitat of Redside Dace. By using a bioengineering approach, we use natural materials in our projects to ensure that our restoration efforts emulate the natural state of the stream as much as possible. In addition to habitat enhancement and restoration efforts, Ontario Streams conducts research in historical and current Redside Dace habitat through electrofishing surveys and water quality monitoring.
Habitat enhancement and rehabilitation activities include:
- Planting native shrubs in riparian areas to assist in bank stabilization, the enhancement of riparian buffers, and to provide overhanging vegetation which will attract the flying insects Redside Dace eat
- Conducting garbage cleanups in riparian and stream areas to instantly improve habitat and to prevent plastic litter from breaking down into harmful microplastics
- Installation of habitat enhancement structures which provide shelter for juvenile fish, prevent erosion, and sediment loading in streams
- Remove barriers to fish movement such as large woody debris blockages, fallen trees, and abandoned beaver dams which would otherwise restrict fish passage
DEVELOPMENT GUIDELINE ENGAGEMENT
The Redside Dace is an endangered fish in the Greater Toronto Area. In 2016, the Ontario Ministry of Natural Resources and Forestry published a guide of recommended mitigation practices for urban development activities in Redside Dace habitat. Uncontrolled construction sediment and urban stormwater entering streams are substantial threats to aquatic species. Ontario Streams is engaging a variety of experts to update the guidance document with recent science-based knowledge of Redside Dace, water pollution, and urban development. Through this engagement process, we will provide updated best management practices to protect Redside Dace!