sentences:  Now, however, the land corridor to Spruce Island is resubmerged, and Spruce Island is once again an island.The once-exposed gravel bar has similarly been resubmerged, becoming a hazard to boating and unfortunately extirpating the colony of common terns and herring gulls that bred there.These two species are no longer commonly seen on the lake now that their breeding site has drowned, but the recent rise in water level is to the apparent benefit of the lake's common loon, red-necked grebe, and beaver populations.