Western grebes overwinter here on Southern Vancouver Island in the protected coastal bays. Three pairs were seen in Pedder bay throughout January and February of 2006. They feed on fish at night following trails of bioluminescence as the fish swim through the water. ( see reference below)
It may surprize some to know that this is one of the few prairie pond birds which do not migrate South during the winter, but instead migrate West over the Rocks mountains to the Coastal Bays of Vancouver Island.
The Western Grebe is classified by the Alberta Government as a Species at Risk. This Field Summary gives further information on it.
Research on Foraging indicating a night-feeding pattern is presented in the research of James Clowater, See the link to his thesis at the bottom.