There is a registry called CAPER, the Canadian Post-M.D. Education Registry. That tracks where graduates set up practice for a period of time, which specialty, etc.
What we do know is that the debt load of medical students is influencing, probably inappropriately, their choice of speciality. Many of them take what is known in the trade as the EROAD. The EROAD is emergency medicine, radiology, ophthalmology, anesthesia, and dermatology. Those are the specialties most associated with so-called quality of life, and that's a combination of income and availability of time for personal pursuits.
We don't know actually where they go in terms of the location in the country. The Canadian Association of Interns and Residents and the National Physician Survey do attempt to track that data, but I believe it's piecemeal.