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http://www.mnr.gov.on.ca/stdprodconsume/groups/lr/@mnr/@fw/documents/document/239841.pdf
Page 28 - 2010/2011 Ontario hunting regulations:
Possession of Accidentally Killed Animals
If you wish to keep the animals referenced below that have
been killed by natural or other accidental causes including
road kills, you must report the acquisition to the ministry.
In the case of black bear, moose, deer, elk and caribou, you must report the acquisition to a ministry office immediately. For specially protected raptors and furbearing mammals, you must make the report within two working days from when you acquired the animal. In addition, anyone who acquires a
specially protected raptor (see Definitions, page 79) must
take the carcass to a ministry office for registration within five
working days of the acquisition. For migratory birds, contact
the Canadian Wildlife Service, Burlington at (905) 336-6410.
For information on keeping the carcass of a big game animal, a specially protected raptor or a furbearing mammal killed in protection of property, see Protection of Property, page 27.
There may be additional requirements regarding the
possession of carcasses of species at risk. For more
information, please visit ontario.ca/speciesatrisk.