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RELATIONSHIP OF BEAVER TO OTHER RESOURCES Wildlife Beaver ponds and associated flooding and high water tables create habitat diversity, edge effect, and vegetative changes that attract wild- life species that are not often found in other areas of the forest. Water- fowl, shorebirds, and songbirds that feed over open water are commonly attracted to flooded areas (Neff, 1957). On the Lolo National Forest in western Montana, American reds tarts (Setophaga ruticilla) were found to in- habit flooded habitats disproportionately than other streamside areas (M. Hillis, personal communication). Furbearer populations, such as mink, muskrat, and otter are also attracted to these pond conditions (Yeager and Rutherford, 1957). Otter have been found to coinhabit beaver lodges and appear to select for beaver ponds when first inhabiting a drainage in Idaho (Wayne Melquist, personal communication). The higher water tables often create vegetative responses that pro- vide cover, forage, or edge effects that are attractive to a variety of wildlife. Perhaps the most noticeable wildlife are the large ungulates. Moose, elk, and whitetail deer in western Montana are commonly found assoc- iated with beaver-influenced habitats in greater density than areas with- out beaver. Water Quality and Quantity The reduction of velocities as a stream flows through beaver ponds results in considerable amounts of sediments deposited in ponds, depend- ing on the age and structure of the ponds. Reductions in stream sediment up to 90 percent have been documented (Smith, 1981). Stream associated resources or uses that are adversely influenced by sediment could be bene- fitted by this reduction. Water temperatures can be modified by ponding action (Adams, 1953; Patterson, 1950; Reid, 1952). A springfed stream could be cooled during winter, while the same stream during summer may have temperatures increased. Trout populations existing in marginally high water temperatures could be adversely affected, while populations in cold headwater conditions could be benefitted by the warming of water resulting in increased basic bio- logical productivity. Beaver have the potential to increase the level of pathogens down- stream from their activities, resulting from beaver excrement. Beaver are one of many warm blooded mammals capable of transmitting the flagel- lated protozoan, Giardia lamblia. As a result, this can be a concern to municipal water supplies without adequate treatment facilities (J. Bonham, in press). Variability in seasonal flows is commonly reduced through the reservoir effect of bank storage adjacent to the ponds. The amount of this storage capability is often quite low relative to the total amount of spring runoff flows; however, as this bank storage is released through late summer, the additional amount of water may be important to water users or resources. 74