Both High Park and Rosetta McClain Gardens Raptor Watches are in the fall. Very little goes through the city in any great concentration in the spring. Raptors fly to the Niagara escarpment and then disperse to their nesting areas during spring migration. Aside from known nests like those on the Peregrine Foundations sites(most viewable but inaccessible) U will be hard done by to get people to tell you where nests are,particularily on open boards such as this. Problem birders and photographers alike make people keep nesting sites to themselves. Easily accessible sites are also kept private so birds arent harassed. There is a well known Redtailed Hawks nest at Queens Park. Ive seen good photographs of that. Watch any wooded areas this time of year,for birds with nesting materials flying around. Accipiters are very secretive,so tough to find. Cavity nesters like Kestrels may also be tough to find. Merlin nests in Toronto are few and far between(some say none). Ive heard a few reports of nesting Vultures,but never seen any myself. Roughlegs,Goshawks,Red-shouldered,Broadwings,either Eagle and Osprey are to my knowledge not known to nest in Toronto(standing to be corrected). Good Luck