While growing up in East York back in the 70's and playing road hockey out in front of the house, my friends and I used to stop and watch as one, two, or even three Nighthawks flew high above the street calling out, flapping their wings to gain height and then diving at high speed with a swoosh like nothing else we'd heard before. It was just fascinating to watch. So sad that I see very very few of them these days.
Last summer I saw one in the College/Dufferin area during the afternoon and heard one a few weeks later around the College/Spadina area late at night.
Walter