The number of waterbirds on the pools within the survey area is monitored to determine population sizes, habitat usage, and the waterfowl's response to management actions. Survey flights ran weekly through the autumn migration, weather premitting. In 2009, the flights covered Pool 2 (backed up by Lock and Dam 2 at Hastings, MN) to Pool 14 (backed up by Lock and Dam 14 at LeClaire, IA). (Map)
Waterbirds Start to Arrive in September
In late September there were a little over 17,000 ducks using the stretch of Mississippi River between St. Paul, MN and Rock Island, IL. By the third week in October, however, that number exceeded a quarter million.
And they arrived suddenly. Pool 9 lies on the river at the Minnesota and Iowa border and has excellent diving duck habitat. Diving ducks included redhead, canvasback, ringneck, scaup, goldeneye, bufflehead, merganser and ruddy ducks. Pool 9 contained no diving ducks on September 30 and only twenty on October 5. A week later that number had increased to 22,655 diving ducks and by October 20 that number had burgeoned to 98,700.