Affected Environment

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NATURAL RESOURCES

BIOTIC COMMUNITIES

The flora of Crater Lake National Park is typical of the vegetation found throughout the Southern Cascades. Generally, the vegetation of the region reflects a mosaic of forested areas and open non- forested areas. Climate, topography, soil development, and fire history all affect the composition and distribution of existing plant communities. Because of this natural species diversity, the park is regarded by many as a sanctuary for native forest and meadow communities, with limited introductions of non- native species. Approximately 20,250 hectares (50,000 acres) of late seral forest exist throughout the park. Fire suppression and historic logging activities have altered forest structure and species composition throughout portions of the park and surrounding areas.

Crater Lake National Park ranges in elevation from about 3,800 feet in the southwest corner of the park to just over 8,900 feet at Mount Scott. Most of the rim area is situated near the 7,000 foot elevation level, although, the Watchman and Hillman Peak areas on the western side of the lake are slightly in excess of 8,100 feet. Vegetation grades from a mixed conifer forest dominated by ponderosa pine at the south entrance to high elevation mountain hemlock and whitebark pine forest at the rim. Other forest types include lodgepole pine, white fir, Douglas fir, and shasta red fir.

Ponderosa pine forest principally occurs on the southeastern edge and northeastern corner of the park, up to elevations of 5,500 feet. The ponderosa pine is commonly associated with white fir and in the lower elevations with sugar pine and some Douglas fir. Along the margin of ponderosa pine communities, particularly at meadow edges where cold air tends to have a large ecological effect, lodgepole pine may be found in association with ponderosa pine. The white fir forest is concentrated in the southern portion of the Park and has a major component of ponderosa pine, as well as sugar pine. Historic fires favored the survival of pines over white fir, and most of these stands, concentrated in the southern portion of the park, were historically dominated by ponderosa pine. The Douglas- fir type is not a common type in the park and occurs in relatively inaccessible areas in the southwestern portion of the Park, where it occurs in a complex mixture with red fir, climax lodgepole, and white fir forests. Increasing in elevation, lodgepole pine forest type sometimes covers vast areas and is found from 5,000- 6,500 feet and is associated with shasta red fir and mountain hemlock.

Climbing still higher, to the very rim of Crater Lake, and up the slopes of the surrounding peaks, the forest becomes more scattered and the trees smaller and more stunted. Only a few species endure the low temperature, high winds, and deep snows at these altitudes, the principal ones being mountain hemlock, and white- bark pine. Mountain hemlock stands are the highest elevation continuous forests at Crater Lake and become dominant at about 6000 feet. Whitebark pine extends from about 7500 ft to the top of Mt. Scott, the highest point in the park (8,929 ft) and is more an open woodland than a forest. Whitebark pine is uncommon in the park and is in decline throughout its range due to a non- native pathogen that causes white pine blister rust in five- needle pines. Information is being collected throughout the Cascades Range that will help land managers to develop appropriate management plans to provide for preservation of this species.

The abundant and diverse vegetation of the park constitutes a large block of relatively undisturbed habitat that supports various populations of native wildlife species. The park has significant populations of Roosevelt elk, black tail deer, pronghorn, coyote, and porcupine. Periodic sightings of black bear, pine marten, weasel, and mountain lion are reported in the summer months. A variety of other small animal species are seen in the backcountry of the Park.

Soil properties are integral components of determining the species diversity, productivity, and regenerative capacity of vegetation types. Therefore soil resources are also included in this impact topic. The Natural Resources Conservation Service (NRCS) completed inventory and mapping of the soils of Crater Lake National Park in 2001. Twelve soil types that fall into six general categories were identified within the park. The categories are: 1) soils on uplands, formed in air-fall deposited ash and pumice; 2) soils on uplands, formed in air- fall deposited ash and pumice over glacial deposits; 3) soils in valleys, formed in ash flow deposits consisting of ash, pumice and cinders; 4) soils on cinder cones; 5) soils on upland meadows with intermingled forests; and 6) soils in seeps and on stream terraces. In general, the soils have a low water holding capacity and nutrient levels. These soil conditions combined with a short, relatively dry growing season make reestablishment of vegetation very difficult. Soils are in general not highly erodible.

THREATENED, ENDANGERED, AND SENSITIVE SPECIES

A number of species may be affected by the alternatives that are considered threatened or endangered in Oregon, that inhabit, or for which potential habitat exists in the park.

Table 5: Threatened, Endangered, and Sensitive Species

*List 1 contains taxa that are endangered or threatened throughout their range or which are presumed extinct. The status of taxa on this list represents its status throughout its range. List 2 contains species that are threatened, endangered or possibly extirpated from Oregon, but are stable or more common elsewhere.

Canada Lynx

The park has over 34,000 acres of potential Canada lynx habitat, consisting of a mosaic of old growth stands providing denning sites and lodgepole forest and meadow foraging habitat. Although the park has conducted three years of extensive surveys for Canada lynx in the park, none have been detected. There is evidence from the past suggesting that lynx previously foraged in the park. The Smithsonian Institute has a Canada lynx pelt in its collection that dates back to 1898. It was trapped along the Wood River just south of the park. Lynx sightings have been reported in the Klamath Basin as recent as 2000, but have not been verified with other substantive evidence such as photos, tracks, or hair.

California Wolverine and Pacific Fisher

These species all have large home ranges, are capable of moving long distances, tend to avoid areas with human activity or development, and require relatively undisturbed habitats that are uncommon outside of the park. Because of large- scale loss of natural habitats throughout both species’ ranges, the high- elevation coniferous forests of Crater Lake that provide forage, denning, and travel habitat for these small carnivores park may be important to their distribution and abundance in Oregon. Although information on these species is limited, old forest structure, including large woody debris for denning (both logs and snags), is an important structural characteristic of habitat for these animals. Ongoing surveys initiated over the past 5 years to determine if wolverines are present in the park have only detected pine martens, although a reliable siting of a wolverine was made in 2000 by a state biologist visiting the park.

Bald Eagle

There is a historic nest site on Wizard Island, and one currently active nest site along the shoreline of Crater Lake. Tour boats are restricted from areas on the lake that are near the nest site. The Klamath Basin has over 70 eagle nest sites and these birds forage in the park. Bald eagles are observed in the Park from early spring, April or May, to fall, usually sometime in October. None are present during the winter months.

Northern Spotted Owl

This old- growth dependent species is at the eastern end of its range in Crater Lake National Park. There are approximately 32,260 acres of lower elevation mixed conifer forests that are considered suitable spotted owl habitat in the Park. This habitat is found in patches throughout the park, with higher density of patches and larger patch sizes southwest of a diagonal line connecting the northwest and southeast corners of the park. All currently known nest locations have been found within areas identified as potential habitat on the west and south sides of the park, but occasional sightings have been documented outside of these areas. The park conducts an annual monitoring program to assess the nesting and reproductive status of owl pairs living in the park. Since 1992, 17 owl pairs have been tracked.

Northern Goshawk

This hawk is rare in Crater Lake National Park. Little is known of the specific habitat requirements for goshawks in Crater Lake National Park but the following general forest management activities are helpful in conserving habitat for Northern Goshawks: (1) retain the upper canopy trees at known or suspected nest sites; (2) retain down wood and logs for prey, particularly squirrel species; and (3) manage stands for understory removal and canopy retention.

Peregrine Falcon

Peregrines nest on cliffs, often near water and forage on a diverse avian prey base. Most habitat and reported activity in the park are from within the caldera. One active peregrine nest site exists within the caldera. Tour boats are restricted from areas on the lake that are near the nest site. There are many potential nest sites available on the cliffs in the caldera. The park conducts annual monitoring of falcon habitat, to determine relative abundance within the park.

Bull Trout

The bull trout is the only known fish species native to Crater Lake National Park. Bull trout are located only in Sun and Lost Creeks. Annie Creek is also within this species range and is considered bull trout habitat, although bull trout do not currently occur there. The park has an active restoration program in progress. This program has resulted in elimination of non- native brook trout from Sun Creek 2000. Follow- up surveys indicate that bull trout are responding well in the wake of their restoration in the creek.

Pumice Grapefern, Shasta Arnica, and Crater Lake Rockcress

All three plants occur in isolated populations along the rim. Pumice grapefern is endemic to raw pumicegravel substrates which are subject to harsh climatic extremes (intense sunlight, dessicating winds, cold nights, etc.). Shasta arnica occurs on dry talus slopes of the rim, often with an eastern aspect. Crater Lake rockcress is found in dry, rocky pumice and intermixed with sparse, open, mountain hemlock forest.

WATER RESOURCES

Crater Lake is near the midpoint of the Sierra Cascade Mountain province of the Pacific mountain system. The park is influenced by Pacific Ocean weather. The majority of storm fronts that pass the north Pacific Coast each winter will result in moisture at Crater Lake. Summer weather is generally mild with clear skies except for occasional thunderstorms, which seldom occur with enough force or volume to produce damaging rains or hail. Daytime summer high temperatures usually range from 60°F (15°C) to 70°F (21°C) and seldom exceed 85°F (29.4°C). Approximately 70% of the annual precipitation falls from November through March, with less than 6% from June through August. During the dry months — June, July, and August — an average of only five days will have precipitation greater than 0.10 inch. Snow has fallen every month of the year. Annual snowfalls can total over 800 inches, and long- lasting snow depths of 100 to 200 inches accumulate.

Waters from the slopes of Mt. Mazama flow into the Klamath, Rogue, and Umpqua River Systems. Runoff channels are broad and poorly defined with rounded contours. This is because surface runoff in the Park from rain and melting snow is negligible. Water sinks almost immediately into the porous volcanic soils and glacial debris and is released only slowly through evaporation, plant use, seeps, and a few springs, some of which emerge within the caldera and flow directly into the lake.

Annie Spring, near the Mazama campground, has been the park’s water supply since 1976. Water is pumped from the spring to storage facilities at Rim Village, Mazama Village, and Munson Valley. The source of water for Annie Spring is shallow groundwater originating as snowmelt; the spring’s output is reduced during years when the winter snowpack is low (Century West Engineering Corporation 1994). The average low flow is about 1,565,000 gpd, or 2.4 cfs. Annie Creek joins with the Wood River and eventually flows into the Klamath River system south of the park.

Crater Lake

Crater Lake lies inside the caldera of Mount Mazama and is surrounded by steep- walled cliffs that range from 500 to 2,000 feet above the lake’s surface. At 1,943 feet, it is the seventh deepest lake in the world and the deepest in the United States and noted for its extreme water clarity and deep blue color. The lake has no surface outflows and only minor surface groundwater inflows as springs along the caldera walls. The main source of water for the lake is precipitation, averaging 70 inches per year.

Results of the ongoing Crater Lake Long-Term Limnological Program indicate that Crater Lake is a complex and dynamic system. No unidirectional change in the parameters monitored (lake and spring water chemistry, nutrients, chlorophyll, primary productivity, phytoplankton, zooplankton, fish, water clarity, light penetration, and temperature) has been detected. The monitoring program has also provided valuable data and recommendations on a number of other management issues including the extent and significance of submerged hydrothermal resources (relative to a proposed geothermal power development along the park boundary), boat and automobile petroleum hydrocarbon inputs to the lake, water quality of springs entering the lake below developed areas along the caldera rim, and the potential impact of introduced fishes.

AIR QUALITY

Crater Lake National Park is a class I air shed designated by the 1977 Clean Air Act amendments. As a class I area, the park is subject to the most stringent regulations of any designation. Results from the park’s air quality monitoring indicate that the condition of the park’s airshed is good, one of the cleanest airsheds in the U. S. There is relatively little impact from fine particulates and visibility is high. The elevation and geography make the park susceptible to winds, which tend to disperse particulates and other pollutants. The clean air allows spectacular views of the surrounding Cascades and Klamath Basin. A major air quality concern is the pollutants from industrial areas introduced at Crater Lake in the form of acid rain and snow. These pollutants threaten both land and water resources, particularly the lake clarity.