Mississauga in the 6th biggest city in Canada and the 3rd biggest on in Ontario with residents of 800,000, but in the same time it is a habitat of great number of fish species reach to 79 species only in Credit river. These are the most famous species:
Brook trout
The Credit river is the most accessible and productive native Brook Trout for catch and release fishing.
Brown trout
This species present in just below the Niagara Escarpment
Rainbow Trout (or Steelhead)
Commonly found in the spring from Lake Ontario to Norval but may also be found in lower Silver and Black Creeks.
Chinook Salmon
This species are closely regulated in the Great Lakes, so you have to review the fishing regulations and rules and strictly comply with.
Other species:
Smallmouth Bass, Largemouth Bass, Northern Pike, Common Carp, Black Crappie, Pumpkinseed (Sunfish), Rock Bass, Yellow Perch and Brown Bullhead (Catfish), etc
5 places to go fishing in Mississauga, to explore more visit
https://www.mississauga.com/whatson-story/9481448-5-places-to-go-fishing-in-mississauga/
Here more other places
https://www.yelp.ca/search?find_desc=fishing+spots&find_loc=Mississauga%2C+ON
and ask for updates & new regulation before start fishing
References
https://www.mississauga.com/whatson-story/9481448-5-places-to-go-fishing-in-mississauga/
https://www.yelp.ca/search?find_desc=fishing+spots&find_loc=Mississauga%2C+ON
Fishing in Mississauga
Take the necessary protective precautions as advised by government to fight COVID-19