As stated in discussions of vegetative recovery, some sites began to 

 provide habitat of this level in portions of the disturbed areas approxi- 

 mately 10 years after disturbance. Most frequently this occurred in over- 

 burden piles. At four sites (Sinuk River, Washington Creek, Penny River, and 

 Kavik River), the only significant use of the disturbed area by passerines 

 and small mammals occurred at the overburden piles even though these sites 

 averaged over 10 years in age. Thus, at sites where gravel removal created a 

 site s ubject to frequent hydraulic stresses, overburden piles not only 

 provided a reas for rapid vegetative recovery, but frequently provided the 

 first useabl e nesting, feeding, and cover habitat for passerines and small 

 mammals. All vegetated overburden piles were found to be of sufficient 

 size to support at least one pair of nesting passerines and one resident 

 sma I I mamma I . The sma llest overburden pile sampled was approximately 9 m x 

 15 m, while the largest was approximately 15 m x 100 m. As was anticipated, 

 the larger piles supported the larger populations. 



PERMANENTLY PONDED SITES 



Many gravel removal operations resulted in significant long-term loss 

 and reductions in vegetative habitats and associated passerine and small 

 mammal populations. However, one gravel removal method frequently led to an 

 increase in local habitat diversity, even though it resulted in a permanent 

 change from original habitat conditions. This increased habitat diversity 

 also frequently led to increased fauna diversity. This method created perman- 

 ent aquatic habitat either by excavating a pit separated from the active 

 floodplain or by scraping a deep depression adjacent to an active channel. 

 Eight sites provided this lacustrine habitat. (Note: the Kavik River and 

 Ugnuravik River pits were not considered in this evaluation; the Kavik River 

 pit had filled in prior to the site visit and the Ugnuravik pit was very 

 small (10 to 15 m in di ameter ) and primarily covered with ma in channel flow.) 



Several parameters at pit sites were qualitatively evaluated (Table 

 31). Increased fauna use was associated with those ponded waters that had 

 high border cover, irregular pit shape, vegetated or graveled islands, high 

 food availability, and a diversity of water depths. Also, pit size appar- 

 ently was a limiting factor, because both Penny River and Prospect Creek 



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