Precipitation is generally low due to shadow effect of the coastal ranges to the west. Islands within the sanctuary are shaped by yearly changes in riverflows. High flows and heavy ice-cover tend to scrape low bars free of vegetation, while others of higher elevation are vegetated by willows and alder. Stable islands grow up in forests of aspen, cottonwood, and white spruce. Since the Migratory Bird Sanctuary is located within the town limits of Vanderhoof, B.C., most public use of the riverfront occurs within the sanctuary.
Local schools make extensive use of the area as their outdoor biological laboratory.
Local naturalists observe birds during migration. The islands of the Nechako River near Vanderhoof, B.C. have traditionally attracted very large numbers of spring migrating Canada geese. The birds use the area for resting and gravelling before moving on to their breeding grounds in the Arctic. Of the estimated 50,000 to 75,000 Canada Geese that migrate in the spring through the Okanagan Valley towards Williams Lake, upwards of 20,000 were observed at the sanctuary in the late 1960s. Numbers declined during the following ten years, but slowly built up again in the late 1970s.