Hi Sable,
Sorry, I'm afraid I have bad news for you, its not a peregrine. Our peregrines nest on ledges - cliffs in the wild, buildings in urban settings. Your raptor is probably a Merlin (another falcon species) or perhaps a Coopers Hawk. Take a look at your bird's tail, Merlins have bars across the tail. Merlins would be my bet as you live in the Maples. They can look very much like juvenile peregrines but they are much smaller. The males sometimes have grey backs, some have malar stripes (moustaches) but they are thin compared with the peregrines.
Merlins don't make their own nests but rather take over old crows' nests, particularly in large spruce trees, but they will use any crows' nest in other tree species. What kind of tree is the bird in most of the time? Merlins and peregrines share alot of similar behaviours - courtship rituals, incubation and brooding, chick-rearing, and some hunting techniques. Merlins don't "stoop" when they hunt like peregrines, they are fast woodland specialists, so they zip through/around/over/under trees, something that peregrines don't do alot, just too dangerous at the speeds they can fly. Merlins also hunt smaller prey - basically birds ranging in size from sparrow to pigeon. And they are exhibitionists when they eat - they love the tops of telephone poles and they are very enthusiastic eaters, lots of feathers flying!
As for bands, chances are it doesn't have any. They have never been an at-risk species but some bird banders do band them when they catch them so its not impossible. If there is a band, don't kill yourself reading it, you won't be able to, the band on them will be a FWS aluminium band which isn't meant to be read at a distance, rather returned to the Bird Banding office in Canada or the US if the bird ends up in rehab/captivity or dies/found dead.
Enjoy your Merlins, they are great birds and having them nest so close is a wonderful opportunity!! If you have/get photos, please do email them to me at peregrinechick [at] species-at-risk.mb.ca.