The first waterfowl arrive in the spring when the ice vanishes in April. The peak migration occurs in late May when 5,000 or more ducks may be present. Canada geese have been reestablished in North Park and begin nesting during April. Duck nesting usually starts in early June and peaks in late June. The forest produces about 9,000 ducklings and 150 to 200 goslings each year. The Fish and Wildlife Service expects that when refuge lands are fully acquired and developed, waterfowl production should increase significantly.