Seems a little late in the year however maybe it is a second brood or they could be young Osprey returning to the nest just because there is no place like home. These two were busy building or repairing a nest as the gathered nearby branches and stuff just east of Guelph on my way home from the Royal Canadian Henley Regatta, a nice break in the drive for a few minutes. I included a photo of the leg band, if you know someone involved with studying the Ontario Osprey, please share it with them, I did do an entry on the banding page however it came back that they are too busy to look into most notifications regarding bands, oh well. 
This leg band appears to be from a study as it is not common for Osprey to be banded.
