as a result of the nine-foot channel project increased backwater areas 

 and hence waterfowl brood habitat. Backwater areas initially expanded 

 submerged aquatic and marsh acreage which form excellent brood habitat. 

 Increased sedimentation and turbidity have decreased the value of brood 

 habitat in the backwater areas by reducing the submerged aquatic and marsh 

 vegetation. Increased effectiveness of management practices has 

 helped keep this duck plentiful even though its habitat has been degraded. 



Canada, blue, and snow geese use-days have increased in recent 

 years. The Illinois River portion of Pool 26 is utilized to a greater 

 extent than the Mississippi River sections. The reason for this in- 

 crease is twofold: (1) a large increase in the continental population 

 of Canada geese (Bellrose, 1976: 142), and (2) increased management 

 practices in the study area by state, U.S. Fish and Wildlife Service, 

 and private duck clubs. 



In conclusion, the nine-foot navigation project initially bene- 

 fited waterfowl populations. Increased backwaters provided shallow 

 areas which supported both marsh and submerged aquatic plant growth. 

 These areas provide additional feeding, breeding, and loafing areas 

 for waterfowl. However, as a result of water fluctuations in Pools 

 25 and 26, waterfowl feeding areas were degraded during several years. 

 The nine-foot channel project has also been a factor which has led to 

 increased sedimentation and turbidity in the Illinois and Mississippi 

 valleys. Increased sedimentation has also occurred as a result of 

 increased erosion from agricultural lands in the watershed. 



Increased sedimentation and turbidity have led to the eventual loss 

 of submerged aquatic plants in most of the project area. This loss of 

 plants has been responsible for declining numbers of wigeon, green-wing 

 teal, and lesser scaup in the project area. In addition increased 

 sedimentation has filled shallow areas created by the project which 

 once supported marsh plants, destroying habitat. On the other hand 

 sedimentation has also created more mud flats which produce moist- 

 soil plants if the proper water level manipulation occurs. 



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