There are about as many anthologies with "Canada" or "Canadian" in their titles as there are anthologies with "American" or "English," roughly 30, per database queries of isfdb. The most comprehensive modern anthologies of Canadian science fiction are two compiled by American editor David G. Hartwell and Canadian editor Glenn Grant. Their first volume focused on familiar genre writers, while the second adds unexpected (at the time) authors like Margaret Atwood and Robertson Davies.
A decade later, Robert J. Sawyer's book focused on both active writers and on award-winning stories, with an appendix of stories and novels that have won any awards for science fiction or fantasy.
Most reprinted authors: James Alan Gardner, Nalo Hopkinson, Robert J. Sawyer, Peter Watts, and Robert Charles Wilson, with 3 each.
Northern Stars: The Anthology of Canadian Science Fiction, David G. Hartwell & Glenn Grant, eds. (Tor, 1994)
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Northern Suns: The New Anthology of Canadian Science Fiction, (Tor, 1999)
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Distant Early Warnings: Canada's Best Science Fiction, (Robert J. Sawyer Books, 2009)
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