The unvegetated and sparsely vegetated areas within arctic and sub- 

 arctic floodplains provide equally valuable habitat for a different segment 

 of fauna. Many of the major floodplains provide key migratory corridors for 

 large numbers of waterfowl, shorebirds, and caribou moving to and from 

 wintering zones and summer nesting and calving territories. Unvegetated 

 areas of larger floodplains are used as prime nesting and feeding habitat by 

 numerous shorebirds, gulls, terns, and waterfowl. The delta areas of larger 

 rivers also are prime Juvenal rearing habitats for shorebirds and waterfowl. 

 Along coastal regions, these river deltas also are key nesting sanctuaries 

 for geese, brant, swans, gulls, terns, and shorebirds, and during late 

 summer and early fal I they provide protected habitat for large concentra- 

 tions of molting waterfowl. Due to the high secondary productivity of these 

 areas, predators including bears, wolves, eagles and jaegers also frequently 

 concentrate their feeding activities along floodplains. 



Unfortunately, from a biological viewpoint, floodplains also provide 

 easily accessible gravels that are available in large quantities and fre- 

 quently close to development sites. As previously noted, arctic and sub- 

 arctic conditions, primarily associated with the presence of permafrost, 

 place large demands upon gravel resources by all development projects. 



During the construction of the Trans-Alaska Pipeline System, over 3,300 

 ha of unvegetated floodplain habitat and approximately 1,000 ha of riparian 

 habitat were affected by gravel removal operations (Pamplin 1979). The 

 proposed construction of a gas pipeline through Alaska, depending upon final 

 route selection and the degree of use of existing construction facilities, 

 could require similar gravel supplies. Other development projects are expec- 

 ted to increase the future demand upon gravel resources. 



Previous to this study, natural resource managers had little indepth 

 knowledge, relative to arctic and subarctic terrestrial floodplain eco- 

 systems, of how to best mitigate the use of floodplains as gravel removal 

 sites. The short-term effects of gravel removal operations were believed to 

 be associated with reduction of habitat, probable decrease in local fauna 

 population sizes, and potential indirect effects through reduced habitat 

 quality in adjacent and downstream habitats. However, the variations in the 



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