I am unaware of any bird reporting site specifically for Grande Prairie. If there was one it would most likely be set up through the Peace-Parkland Naturalists Club based in Grande Prairie. Contact:Margot Hervieux. The other option is to check:Alberta Birds which has birders from all across the province reporting there sightings on a regular basis. As for the sighting of the Barrow’s Goldeneye living in Grande Prairie I would think that given the geographic location of the city it may not be that uncommon as the Barrow’s occur in the foothills
Also the Trumpeter Swans reported from Saskatoon L are breeding birds at that location & may be mixed in with migrating Tundra Swans so check them carefully. Trumpeter Swans are endangered so I don't think there would be hundreds at one time on the lake even if birds from Alaska or other northern breeding populations arrived here at the same time.