Ecology of Non-Breeding Waterfowl in the Wabash River Region Annual Report 2011

Anecdotal evidence indicated that the Wabash River region of Illinois may provide extensive habitat for spring-migrating waterfowl; however, no information exists on the abundance and distribution these birds in this area. Therefore, we conducted 9 aerial inventories of waterfowl in the Wabash River floodplain bordering Illinois and Indiana between 14 January and 12 April 2011. We recorded locations where >1,000 ducks were present and returned to these sites to record waterfowl behavior. Waterfowl abundance peaked on 8 Feruary at 311,545, although nearly half (140,000) of these were lesser snow geese. During early surveys, most birds congregated on Gibson Lake, a power-plant cooling lake. Birds spread out after ice-out and waterfowl abundance declined to approximately 15,000 to 29,000 during subsequent surveys, before falling to <2,000 on 12 April. Waterfowl spent most time feeding (50.7%), followed by locomotion (21.7 %), comfort movements (11.7%), alert (7.9%), resting (6.7 %), courting (1.0%), and agonistic (0.3%). We will use these data to improve the survey design if appropriate and suggest our preliminary results support the notion that important habitat for spring-migrating waterfowl exists in the Wabash River region.