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morning; 11. low temperatures and snow depth force the congre- gation of animals which increases their susceptibility to predation; 12. food availability eliminates many of the weaker animals; 13. migrational movements from one range to another are influenced by time and/or weather; 14. spring storms can reduce the condition of animals and/or reduce the number of individuals in a population; 15. food habits of some species change with the amount of precipitation which can be beneficial or detrimental; and 16. use of south faci ng slopes for food and north faci ng slopes for protection.1I [16,p. 8J Studies of the response of small mammals to winter snow accumulation in the San Juan Mountains [10J do not reveal clearly predictable responses. Lower population numbers seem to occur after winters with late snowpack and late melt. The proximate cause seems to be spring-. time shortage of proper food and a shortened breeding season. Other factors, such as changes in land use, appear to have a more direct effect on small mammal populations. The Skywater Programmatic FES states: liOn the basis of the above findings, it is expected that the Skywater programs of field experimentation will have no dis- cernible impact on small-mammal populations. The potential impact of widespread or prolonged application of precipita- tion management will probably involve occasional episodes or circumstances resulting in temporary declines in small-mammal populations. Because of the large population fluctuations that normally occur, decl i nes caused by these infrequent epi sodes will be difficult to identify or attribute to specific causes. There appears to be little likelihood that such applications will significantly affect the range of diversity of small-mammal species.1I [2, p. 3-131J The effect of additional precipitation on furbearers, reptiles, insects, and birds has not been considered a controlling factor to the well-being of the various species. Migratory birds would not be affected by winter snowpack increase unless highly augmented snow- packs persi sted so as to interfere with breedi ng seasons or food supply - an unlikely occurrence. Residents are well adapted to conditions of an area, and vary their location/elevation in alpine settings according to weather conditions. Habitat destruction or alteration is the most serious factor in the well-being of bird populations. Cloud seeding will not contribute to this occurrence. Increased snowme lt wi 11 benefit marshes and meadows and the an ima 1 s that inhabit them. One of the design considerations for the proposed demonstration phase and for operational activities is to determine the type of monitoring required to determine the response of large and small mammals and their well-being to increases in snowfall and snowpack. Knowledge of the potential impact of precipitation management on the principal components of the aquatic ecosystems is limited. An 18