This is on page 11 of the
2023 Ontario Recreational Fishing Guide:
"Open Seasons – Fishing season opening and closing dates vary depending on the species and the area. Dates are inclusive: all dates including the first and last dates stated in the summary are open or closed. It is illegal to attempt to catch fish for which the season is closed, even if you are going to release them. Fish accidentally caught during the closed season must be immediately released back to the water. Unless stated otherwise, species that are not listed (e.g. Rock Bass) have a year-round open season for angling."
I didn't see any exceptions spelled out anywhere about bass particularly checking Zone 19 (includes Lake St. Clair) and Zone 16 - the main part of Ontario along the St. Clair and Lake Erie waters. A few years ago I believe they 'liberalized' bass fishing season in one of the northern zones of the province. Don't recall which off the top of my head, but it was just a longer season, not year-round I believe.
When you ask some Ontario biologists they say they are 'protecting the spawn' though there's easy arguments that can't be very productive considering the Michigan season, seasons for other gamefish that overlap, and their own regulations in zones that open during the bass spawn. This idea of 'protecting the bass spawn' has been beaten to death considering only 3 states still have a 'closed season' but allow catch and release, and/or open before the majority of their bass spawn.
In Michigan, 70% of the bass spawn statewide happens AFTER the Memorial weekend bass 'harvest' opener. That's been true for 52 seasons. That's not me saying that. The MDNR handed out a statewide bass spawn map during the last bass season change stating 70% of the bass spawn happens AFTER Memorial weekend including almost all of the Northern smallmouth bass spawn that gets people so worked up about 'protecting the spawn.'
