Thanks for comments.
I noticed the hawk in my image, starting to hunt down the mallards in early February. After looking at the images, I thought too that it could be a young hawk. Over many years observing the High Park and Grenadier Pond, I never noticed this phenomena, a high predation by hawk on mallards and other birds to such an extent. Others noticed a hawk taking down woodpecker, attacking cardinals and mallards at "bird's sanctuary".
Regarding the hawks being comfortable around people, I was wondering if they were just so hungry because the squirrels were not out during extremely cold February or if these hawks potentially were released and are more familiar with people.
Yesterday, on Wednesday, March 4, I also saw the bald eagle, apparently seen around High Park in the past 6 weeks or so, by many others. At dusk, he was flying majestically over Grenadier Pond, slowly and fairly low, then disappearing at the north end heading towards west. In my opinion, this specimen is fairly big adult and his head was strikingly white.
I am wondering how the eagle's presence in the park has influenced other raptors, as they are very territorial. Also, the park always had a couple or two or the residential hawks but it could be that this winter pushed more hawks into the park.