I don't see a conflict for the SPCA.
If they believe that drowning beavers and other small water animals is cruel, they should speak out - to the council, to the Wildlife Branch, and to the public.
I don't believe the SPCA has ever lost a contract because they were pro-active in animal welfare.
I am always wondering why I see them out promoting petitions to end cruelty to animals, and yet when we have a clear case of cruelty to animals, such as this, the SPCA hasn't been heard from.