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<br />, <br />, <br /> <br />~3l\ <br /> <br />(Stromberg & Patton, 1991). Coyote and Bebb willow reproduce by seed and likely require a <br />similar sequence of events. Other factors which contribute to regeneration success include the <br />health of the parent tree and temperature and moisture conditions during flowering, pollination, <br />seeding, sprouting, and seedling grov.1h. These factors are affected by the long and short term <br />panern of streamflow. Regeneration, survival, and growth of other species of riparian <br />vegetation found within !.he proposed wilderness are not as well understood. <br /> <br />All ecosystems are disturbed from time to time and bave developed under a certain panern of <br />disturbances. Flooding is one of the main forces of disturbance in riparian ecosystems. <br />Riparian plant species, including alder, willow, and red-osier are adapted to periodic flooding <br />and may benefit from such eventS (Windell, 1986). Upland plant species which might <br />encroach into riparian areas are not adapted to the dynamic nature of riparian ecosystems and <br />the pattern of streamflow eventS. They normally cannot survive over the long term in a <br />riparian setting. Modification of the pattern of disturbance, such as reductions in the <br />frequency, magnitude. or duration of flooding, would affect the ecological processes <br />maintaining the riparian ecosystem and the position and size of the riparian zone. For <br />example, the cottonwood communities are particularly vulnerable to reduction or elimination of <br />flood flows. <br /> <br />Vegetation intluences the adjacent aquatic ecosystem by contributing leaf debris. which serves <br />as a food source to aquatic insectS; by mooerating water temperatures through the shading <br />provided by overhanging vegetation; by providing habitat for terrestrial insects which fall into <br />the stream and supplement the diet of fish; and by serving as a source of logs and branches that <br />shape local channel morphology, provide and retain organic matter, and provide overhead <br />cover and shading for fish. The root systems also act to stabilize stream banks. debris dams. <br />and gravel bars (Meehan. 1991). <br /> <br />River otters were tiest reintroduced in the Piedra River in 1979; additional otters were released <br />in 1982. They are a State listed endangered species. The released otters have distributed <br />themselves between Navajo Reservoir and Williams Creek Reservoir. Because otters are very <br />elusive and mobile. there are no reliable estimates of total numbers. Although there have been <br />few confirmed sightings of otter within the wilderness. continuing evidence of their presence <br />includes tracks and scat along the stream and signs of their feeding activities. They are <br />carnivores and feed principally on fish and to some extent on other aquatic organisms like <br />insects. crayfish, and snails. Riparian vegetation provides cover and shelter for otters. <br />Streamside vegetation improves the probability of eluding predators. and driftwood piles serve <br />as resting areas and locations for territorial marking. <br /> <br />Bald eagles. a Federal and State listed endangered species. have been observed along the <br />river. It is used by eagles as a travel corridor b~tween :-.l'avajo and Williams Creek <br />Rl$ervoirs and as a transitory hunting area. Th~ willow tlycatcher and Lewis' woodpecker <br />are riparian dependent species which may be present in the proposed wilderness. lewis' <br />woodpecker uses cottonwoods for nesting. The Division of Wildlife considers these two <br />species to be of undetermined status; this means they are of managmem concern due to <br />habitat loss and potentially low population numbers (Skiba. 1991). <br /> <br />Page 7 <br />