Where Are the Ducks
breeding grounds in the Dakotas, Minnesota and Wisconsin are dotted with nearly 20 million acres of wetlands. Even more wetlands are found on the prairies in southern Canada.
The mid-latitude states of Missouri, Kansas and Illinois represent the bottleneck in the hourglass with only 2.3 million acres of wetlands. This region is bound by the Missouri River and its tributaries to the west and the Mississippi River and its tributaries to the east. States to the south still have 19 million acres of wetlands.
So what does this bottleneck and the loss of habitat mean for the millions of ducks that migrate south each fall? Missouri accommodates about 32 million duck-use days (a duck-use day equals the number of ducks times the number of days they are here) each fall. The region that produces the ducks that migrate through Missouri has a breeding population of about 19 million ducks. In a normal production year, a fall flight of about 38 million would be expected. If all of these ducks stopped in Missouri for just 10 days, we would support nearly 400 million duck-use days!
Of course, not all ducks from this region migrate over Missouri. But it does suggest that Missouri has much more potential to accommodate more than the 32 million duck-use days it now supports.
Effects of Adding Wetland Habitat
Another way to see if Missouri has reached its carrying capacity for migrating waterfowl is to review how ducks have responded to the restoration of wetlands in Missouri. In the last 15 years, the Department of Conservation has restored more than 25,000 acres of wetlands, and the Natural Resource Conservation Service (NRCS) has restored an additional 100,000 acres on private land. The ducks have responded.
The number of duck-use days on managed state and federal wetland areas in Missouri jumped from an average of 21.2 million in the 1970s to 32.1 million from 1994–2004. Hunters have reaped the benefits. Before these restorations, the statewide harvest topped 300,000 only once from 1961-1996. Since 1997, the harvest has never been below 300,000, and it frequently has topped 400,000. Missouri’s share of the flyway harvest has increased from about 3 to 4 percent to 6 percent.
But have these restorations been too much of a good thing? Have we restored so much habitat that new habitat is now pulling ducks away from existing habitat? This does not appear to be the case.
Eight of the top 10 counties for