Northern Prairie Wildlife Research Center
The mallard (Anas platyrhynchos) comprised 8.0% and the tufted duck (Aythya fuligula) 2.4% of the total breeding population in 10 sites studied. Reclamation, pollution, and recreation are obvious threats, but new pressures are continually arising. As the demand for water-based recreation continues to increase, it seems likely that gravel pits will face even more pressure than natural wetlands.