TABLE OF CONTENTS

The Ecoregion Defined

Geology

Climate

Soils

Vegetation

Wildlife

Human History

Current Socio-Economic Conditions

First Nations

Other Settlements

Socio-Economic Conditions and Concerns

Energy Flow

Biogeochemical / Nutrient Cycles

Soil Formation / Soil Erosion

Hydrologic Cycle

Human Activities

Timber Harvest

Water Diversion / Hydropower

Livestock Grazing

Agricultural Irrigation

Contaminants

Urbanization

Introduction of Exotic Species

Alteration of Disturbance Regimes (Fire, Flooding, etc.)

Ecological Effects of Human Activities

Soil Loss

Hydrological Disruption

Habitat Loss

Habitat Degradation

Habitat Fragmentation

Successional Disruption / Altered Disturbance Regimes

Altered Disturbance Regimes

Air Pollution

Displacement by Exotics

Overexploitation / Persecution

Species Loss

Fish

Amphibians and Reptiles

Birds

Waterfowl

Seabirds

Colonial Waterbirds

Raptors

Marsh and Shorebirds

Neotropical Migrants

Resident / Upland Birds

Mammals

Carnivores

Rodents

Bats

Ungulates

Invertebrates

Plants

Conclusions

APPENDICES

Table I-1. Temperature Regimes for Eight Stations within the Klamath Ecoregion.

Table I-2. Mean monthly distribution of precipitation for eight stations within the Klamath Ecoregion.

Table I-3. Erosion rates for selected sites in Klamath Ecoregion in geologic past.

Table I-4. Vegetation series within the Klamath Ecoregion (from Sawyer and Keeler-Wolf (1995)).

Table I-5. Wildlife habitat types represented in the Klamath Ecoregion (based on Mayer and Laudenslayer 1988).

Table I-6. Vegetation types derived from Landsat thematic mapper classified into Wildlife Habitat Relationship (WHR) classes ("Fox Habitat Types").

Table I-7. Vertebrate species found within the Klamath Ecoregion.

Table I-8. Indian tribes within or from the Klamath Ecoregion.

Table I-9. Total population of principal counties within the Klamath Ecoregion in 1990.

Table I-10. Income level by county for the Klamath Ecoregion.

Table I-11. Educational attainment by county for the Klamath Ecoregion.

Table I-12. Unemployment rates by county for the Klamath Ecoregion (April 1998).

Table I-13. Erosion rates for selected sites in the Klamath Ecoregion in the geologic past.

Table I-14. Critical phenomena and points in the hydrologic cycle of the Klamath Ecoregion.

Table I-15. Reported fire return intervals for some forest types found within the Klamath Ecoregion.

Table I-16. List of impaired waterbodies within the California portion of the Klamath Ecoregion (from California Regional Water Quality Board (1996)).

Figure I-1. The Klamath / Central Pacific Coast Ecoregion (DEM map)

Figure I-2. Ecoregions of the United States.

Figure I-3. The Klamath / Central Pacific Coast Ecoregion.

Figure I-4. Potential Natural Vegetation of the Klamath / Central Pacific Coast Ecoregion.

Figure I-5. The Klamath Economic Zone with comparisons with Klamath Basin, Klamath Province, and Klamath Basin.

Figure I-6. Geology of the Klamath / Central Pacific Coast Ecoregion.

Figure I-7. Soils of the Klamath Ecoregion.

Figure I-8. Soil sensitivity of Klamath Ecoregion

Figure I-9. Mean monthly distribution of runoff at selected gaging stations.

Figure I-10. The fog belt within the Klamath Ecoregion.

Figure I-11. Wildlife habitat types from Landsat thematic mapper ("Fox habitat types").

Figure I-12. Linguistic stocks for Native Americans of the Klamath Ecoregion.

Figure I-13. Tribes of Native Americans from the Klamath Ecoregion.

Figure I-14. Location of rancherias and reservations of the Klamath Ecoregion.

Figure I-15. Human population densities for the Klamath Ecoregion.

This volume is the first of three volumes describing a strategy for restoring the function and health of the Klamath / Central Pacific Coast Ecoregion (Figure I-1), hereafter termed the "Klamath Ecoregion." In this volume, we describe the ecoregion from an ecosystem perspective and summarize some of the human forces that have caused or are continuing to cause ecosystem degradation.

In volume II, we describe the critical ecological issues of the ecoregion. These "ecoissues" are the result of human activities that are causing major disruption of the ecoregion's health and function.

In volume III, we describe a holistic strategy for addressing these ecoissues. This includes both a description of existing plans and programs for resolving ecoissues as well as proposals for new initiatives.

The boundaries of the ecoregion and the rationale for such delimitation are described in more detail in the following section. Basically a stretch of Pacific coastline forms one boundary and the watersheds draining along this coast define the region. However, the scope of this report is focused upon the terrestrial and freshwater landscape, with minimal attention to coastal issues. Thus the report deals with anadromous fish and shorebirds but does not attempt to deal with issues such as those of marine mammal or tidepool conservation. To do justice to these many coastal issues in even the most cursory way will require a report comparable to this one. We hope that such a report and strategy will be produced in the near future as it would provide a nice complement to this effort.

The Klamath Ecoregion is one of 52 ecoregions (Figure I-2) defined by the U.S. Fish and Wildlife Service. It is located in northwestern California and south-central Oregon and consists of all the watersheds or hydrobasin that drain into the Pacific Ocean north to the Smith River (Figure I-3). Thus the ecoregional boundaries are defined in terms of watersheds rather than some other criteria such as geology or vegetation type.

Any ecoregional delineation is bound to be arbitrary. Some interactions occur between ecoregions and thus any delimitation of an area is not going to encompass all species or ecological processes. However, the Klamath Ecoregion boundaries are biologically meaningful in many ways. It encompasses most of the range of coast redwoods. Mapping of potential natural vegetation of the ecoregion indicates that it contains virtually all of the potential natural sites for one vegetation type (Pine-Cypress forest) and most of the sites for four others (Redwood forest, California mixed evergreen forest, Montane chaparral, and Fescue-oatgrass) (Figure I-4). Together, these five types make up more than 50% of the ecoregion.

The ecoregion also encompasses most of the Klamath Economic Zone (Figure I-5). The Klamath Economic Zone is based on the biology of salmon. Salmon are a keystone component of the ecoregion, not only ecologically but also economically and culturally. The Klamath Economic Zone, which includes the Klamath Ecoregion as well as the Rogue River drainage to the north, is managed as one unit for purposes of allocating ocean salmon harvesting since stocks from these rivers are found together in the ocean fishery. The Klamath Economic zone is the most inclusive of the ecoregional designations--including all of the Klamath Basin, Klamath Province (as defined by the President’s Forest Plan) and Klamath Ecoregion as shown in Figure I-5.

Figure I-1. The Klamath / Central Pacific Coast Ecoregion (DEM Map).

Figure I-2. Ecoregions of the United States.

Figure I-3. The Klamath / Central Pacific Coast Ecoregion.

Figure I-4. Potential Natural Vegetation of the Klamath Ecoregion.

Figure I-5. The Klamath Economic Zone.

The Klamath Ecoregion encompasses portions of four geologic provinces: Coast Ranges, Klamath Mountains, Cascade Range, and Modoc Plateau (Figure I-6).

Coast Ranges Geologic Province

This province is located along the coastal portion of the ecoregion from Sonoma

County to the Oregon border. It includes the entire watershed of most of the smaller coastal streams as well as portions of the Smith River and Klamath River hydrobasin. It consists of a system of north and northwest trending mountain ridges and valleys formed by folding and faulting. The geologic history of this province is complex. The exposed stratigraphy suggests long periods of marine deposition, plutonic intrusion, and intermittent volcanic activity and orogeny.

The predominant formation in the Coast Ranges is the Franciscan Complex of Upper Jurassic and Lower Cretaceous age. Franciscan Complex rocks include graywacke, metagraywacke, argillite, greenstone, chert, blueschist, and associated ultramafic rocks and serpentine. These rocks have undergone periods of intense folding, faulting, and deformation associated with the complex process of tectonic plate movement. The complex Franciscan Formation is divided into three northwest trending belts. They are an eastern belt of metaclastics, a central belt dominated by melange, and a coastal belt of graywacke, shale, and conglomerate. Cretaceous marine formations do form a zone along the coast and lie west of the Franciscan Complex. The Cretaceous marine formations are sandstone, shale and conglomerate. The rivers of this province mostly run south/north or north/south paralleling the underlying rock formations and fault lines.

Klamath Mountains Province

The Klamath Mountains geologic province covers an elongate north-trending area of approximately 12,000 miles square in northwestern California and southwestern Oregon. It includes many individual mountain ranges including the Yolla Bolly, Trinity, South Fork, Salmon, Trinity Alps, Scott, Scott Bar, Marble and Siskiyou Mountains. It has had a long and complex geological history described in detail by Irwin (1966).

This province contains a variety of metamorphic, sedimentary and igneous rocks of various ages. A principal feature of the Klamath Mountains Province that distinguishes it from the Coast Ranges Province is the presence of granitic intrusions of rocks that range from hornblende diorite to true granite in composition. Such rocks are lacking in the Coast Ranges.

Figure 6. Geology of the Klamath / Central Pacific Coast Ecoregion.

A principal feature of the Klamath Mountains is the presence of "peneplains" which are elevated land masses with flattish or gently rounded summits with an approximate accordance in the altitudes of even-crested ridges, given the appearance of a dissected plateau. These areas are particularly important biologically because many of them occur at relatively high altitudes and thus have not been subject to the periodic fresh or saltwater inundation typical of the Coast Ranges and the lower portions of the Klamath Mountains. As a result, species of plants and animals have remained in place or evolved over long periods in such areas, with resultant high degree of endemism and species richness.

The complex rock pattern and history of the Klamath Mountains have produced no well defined trend in stream drainage and ridge direction such as is found in the Coastal Mountain Province. The principal rivers of the Klamath Province cut transversely across it, running generally westward from the interior valleys, through deep canyons in the mountains themselves.

Cascade Range and Modoc Plateau Provinces

The upper Klamath River basin is within the geologic provinces of the Cascade Range and Modoc Plateau. The Cascade Range extends northward through Oregon and Washington into British Columbia and the Modoc Plateau extends into Oregon and southeastward into Nevada. Most of the Cascade Range is a fairly well defined province, but in the Upper Klamath Basin the separation between it and the Modoc Plateau becomes indefinite.

The outstanding characteristics of the Modoc region are: (1) the dominance of volcanism so recent that the volcanic landforms are still clearly preserved (the most well known being Crater Lake and Mount Shasta); and (2) the presence of broad inter-range areas of nearly flat basalt plains. The basalt plains have given rise to the designation "plateau," however, the region as a whole is not a high, undiversified plain as the name suggests.

The upper Klamath Basin region of the Modoc plateau supports some large and geologically old wetlands. The river systems of this area were once connected with both the Snake River drainage to the north and east, as well as to the Sacramento and San Jouquin drainage to the south. Upper Klamath Lake is one of the oldest freshwater lakes in North America of its size. Frest and Johannes have stated: "Upper Klamath Lake is one of the few surviving Pliocene lakes and the only one with normal alkalinity and a large relict fauna. It is likely the best remaining window on environments prevalent in the interior West 2-17 million years ago."

The basic climate of the ecoregion may be characterized as Mediterranean with warm summers with little or no rain during summer and wet and cool winters. This pattern varies considerably from one portion of the ecoregion to another, particularly with regard to precipitation. Mean annual temperatures for eight locations (Santa Rosa, Ukiah, Covelo, Eureka, Crescent City, Weaverville, Yreka, Klamath Falls) within the ecoregion are shown in Table I-1. Mean annual precipitation and monthly precipitation distribution for six locations in the ecoregion are shown in Table I-2. Note that although total precipitation varies considerably from 70 inches in Crescent City to 14 inches in Klamath Falls, the annual pattern is quite similar.

The Coast Ranges generally have the most typical Mediterranean climate with cool wet winters, snow only at elevations above 2,000 feet or more and dry summers with virtually no rain during July and August and more than 70% of the precipitation coming between November and March. However, areas quite close to the coast may get summer precipitation and considerable amounts of fog and fog precipitation.

The Klamath Mountains as well as higher elevations throughout the ecoregion have a somewhat modified climate. They receive some summer precipitation from thunderstorms although this is often spotty. In addition, much of the winter precipitation may come in the form of snow, and higher elevations may accumulate considerable snow packs.

The Modoc Plateau sits in the rain shadow of the Klamath Mountains and as a result has substantially less rain than in the coast ranges as can be seen by comparing the precipitation for Klamath Falls with the coastal cities of Eureka or Crescent City. Summer temperatures also tend to be warmer for similar elevations, but because most of it sits at higher elevations, summer temperatures are generally cooler.

Soils vary considerably throughout the ecoregion in both their fertility and their sensitivity to disturbance. A generalized soil map and soil sensitivity map are shown in Figures I-7 and I-8. Throughout much of the Coast Ranges, the sedimentary soils of Franciscan formation are notoriously fragile. Because of their complex geologic history, the Klamath mountains have a diversity of soils ranging from decomposed granitics to volcanic soils. In places there are quite old and deep soils due to long periods without inundation or glaciation. The volcanic soils of Modoc Plateau notoriously porous and by contrast to the Franciscan soils of the Coast Ranges are quite resistant to erosion from human activities.

S.E. Rantz described in detail patterns of precipitation and runoff for the ecoregion. He presents four hydrographs (Figure I-9) which typify the differing hydrology as one moves from the Coast Ranges to the Klamath Mountains to the Modoc Plateau.

Hydrology of the Coast Ranges is typified by high winter runoff and/or infiltration and perennial streams that are groundwater fed. This is typified by the hydrograph for the Eel River (Figure I-9). With little or no summer precipitation the ability of the soil to capture and hold precipitation is quite critical to the hydrological cycle. It has been estimated, for example, that the soil of the Eel River Basin holds about 233 billion gallons of water, or about 120% of the amount in Lake Shasta when it is full.

Another unique aspect of the hydrologic cycle in the Coast Ranges is the input of water from fog precipitation or "fog drip." The fog belt, or region that receives regular fog, covers approximately 1/3 of the Coast Ranges (Figure I-10). Fog drip is the water that is physically captured by plants, especially large conifers such as redwoods. This is a critical form of precipitation for many plants including especially redwoods and associated flora. Todd Dawson, for example has shown that water from 22-46% of the moisture input to the redwood ecosystem was due to the presence of redwood trees themselves. He further demonstrated that some understory plants derive up to 100% of their water from fog drip and concluded that the presence of trees has a real influence on the magnitude of water input from fog.

Fog drip may also be a significant source of water for recharging aquifers and streams; although this aspect has not been studied in detail in the Klamath Ecoregion there is evidence from other regions that fog drip may be a significant source of groundwater recharge.

The hydrology of the Klamath Mountains is similar to that of the Coast Ranges except that there is no fog precipitation, and significant amounts of precipitation fall as snow rather than as rain. This storage of snow in the mountains and resultant snowmelt results in peak flows in April and May as typified by the hydrograph for the Trinity River (Figure I-9). In addition, there is some summer precipitation from thundershowers.

The Modoc Plateau differs from the other areas in that precipitation input is significantly lower due to the rainshadow effect of the Klamath Mountains and because of the good infiltration of water due to the presence of porous soils. In addition, the underlying rocks are not as permeable resulting in a high water table in many places. This results in a much flatter hydrograph as typified by Fall Creek and the Shasta River (Figure I-9).

Figure I-9. Mean monthly distribution of runoff at selected gaging stations (from Rantz 1964).

The vegetation of the ecoregion is as diverse as the climate and landforms ranging from semidesert Great Basin types to coastal marshes and rainforests. Vegetation of a defined area can be described in many different ways depending on: (1) the scale at which the vegetation is being described, (2) the method of data collection; (3) the classification system used, and/or (4) the purposes for which the vegetation description is to be used. This often leads to much confusion among those who are not botanists or plant ecologists. We describe here the vegetation of the Klamath Ecoregion in three different ways, in terms of "potential natural vegetation" at the "formation" level, existing vegetation at the formation level, and existing vegetation at the "series" level. These represent represent two quite different levels of scale. In the following section on wildlife, we describe two additional systems for describing vegetation of the region in terms of its utility as habitat for wildlife.

Potential Natural Vegetation

Potential natural vegetation of the Klamath Ecoregion is shown in Figure I-4. These are the vegetation types that can or would theoretically occur in a region in the absence of both human and natural disturbance and without major climatic change. In reality, over long enough periods of time both disturbance and climatic change always occur and thus such a homogenous vegetation coverage is never attained at a single moment in time. However, such maps are useful in providing a statement about the potential of large regions to support different types of vegetation based upon geology, physiographic features, climate, and soils.

Major Vegetation Types (Formations)

Major vegetation types or "formations" represent coarse scale descriptions of vegetation across large regions (watersheds, basins, ecoregions). This classification is at the same scale as the potential natural vegetation of Kuchler but is intended to be used to describe existing vegetation. Thirteen major vegetation types occur within the Klamath/Central Pacific Coast Ecoregion based upon Terrestrial Vegetation of California (Barbour and Major 1988) and Natural Vegetation of Oregon and Washington (Franklin and Dyrness 1973).

Coastal Prairie and Northern Coastal Scrub. The fescue-oatgrass grassland, or coastal prairie, occurs along the California coast from Santa Cruz northward. Coastal prairie is a discontinuous grassland below 1,000m in elevation and seldom more than 100 km from the coast. Typically it occurs on the ridges and south-facing slopes, alternating with forest and scrub in the valleys and on north-facing slopes. The dominant perennial grasses in this type are Idaho fescue, red fescue, and California oatgrass. The dominant species of the coastal prairie vary from north to south and with distance inland from the ocean. The Northern Coastal Scrub community extends in a narrow coastal strip from southern Oregon to Point Sur, Monterey County. It is dominated by evergreen shrubs less than 2 m tall, but with an additional herbaceous element to the extent that the scrub is interrupted by patches of Coastal prairie. Important shrubs include coyote bush, seaside wooly sunflower, salal, varicolored lupine, monkey flower (Mimulus aurantiacus), and California blackberry. Perennial herbs and grasses are also prominent. This habitat type is relatively stable, with small-scale changes related to agricultural uses and some losses to urbanization in limited areas.

Beach and Dune. The flora, vegetation, and microenvironment of beach and dune are sufficiently different to warrant their separate classification. Beach is defined as the expanse of sandy substrate between mean tide and foredune or, in the absence of a foredune, to the inland reach of storm waves. The beach is characterized be a maritime climate, high exposure to salt spray and sand blast, and a shifting, sandy substrate with low water-holding capacity and low organic matter content. With the exception of sea rocket species, beach taxa are perennial. Many, but not all, share the following traits: herbaceous, evergreen, succulent, leaves entire, habit prostrate, leading to nearly complete burial in hillocks of sand. Dunes are defined to include the sandy, open habitat which extends from foredune to typically inland vegetation on stabilized substrate. Plant communities are generally characterized by the following habitats: moving dune, stabilized ridge, vernal pool hollow, and dune forest. In some areas, extent of beaches and dunes have increased over the past several decades. However, there is a general trend toward lower habitat quality due to increasing recreational use, invasion of exotic plants, and, in limited areas, urbanization.

Coastal Saltmarsh. Coastal saltmarshes are restricted to the upper intertidal zone of protected shallow bays, estuaries, and coastal lagoons. Physical conditions are dominated by the tides, and pronounced environmental gradients are established in response to elevational changes in frequency and duration of tidal flooding. Humboldt Bay is the principle site of coastal salt marshes in California. Dense-flowered cordgrass, an introduced species, remains the usual primary colonist of the tideflats but often shares dominance of the low marsh with common pickleweed. Although pickleweed remains abundant in the high marsh, it often occurs as a codominate with saltgrass and jaumea. During the past few decades, declines in coastal salt marshes have been arrested. Most coastal marshes are now in public ownership. Principal threats include non-point source pollution and susceptibility to oil spills.

Closed-Cone Pines and Cypress. Closed-cone pines and cypress are unique, disjunct plant communities scattered the length of California's coast, mountains, and islands. The relict species occur on infertile and sometimes unusual substrates. Most stands are influenced by maritime climate. A number of endemic species are associated with these communities, and general plant diversities and densities tend to be reduced on these impoverished sites. The reduced pine species occurring naturally within the Klamath Ecoregion include the knobcone pine, Bishop pine, beach pine, and pygmy pine. Cypresses of the region include 7 unique forms (McNab cypress, Sargent’s cypress, Baker’s cypress, Port Orford cedar (Lawson cypress), Gowen cypress, and pygmy cypress. The latter is largely confined to a narrow strip of the Mendocino coast and several of the others are relatively rare. The life cycle of these major species is intimately related to fire. They are characterized by a closed-cone habit or by serotinous cones, whereby the ovulate cones remain sealed after maturity, usually accumulating on the tree until opened by fire. Many of these habitats are in isolated areas or fragile, unproductive soils where there is little economic impetus for alteration. Consequently, these communities are relatively stable, and there has been little concern until recently about them. However, with increased encroachment for development upon the pigmy forest of the coastal zone, increased alteration from logging within habitat of the Port Orford cedar, and logging and alteration of fire regimes within the Klamath Mountains from logging and fire suppression, the security of many of these communities is increasingly threatened.

Coastal Forest. Redwood forests are tall, dense, needle-leaved, and evergreen. Dominant species are redwood, Douglas fir and Sitka spruce. Broad-leaved evergreen medium tall trees gradually increase eastward. The coast redwoods are the tallest trees (112m), growing at rates near world maximum. Undergrowth is low and patchy with forbs mainly on alluvial sites, shrubs and low trees on the uplands. Redwoods are found mostly on the western side of Coast Ranges from Monterey county to just beyond the Oregon border. The redwood belt is usually only about 16-24 km wide, and corresponds well to the fog belt. The redwood "rainforest" is unique in that it resides on the edge of the Pacific Ocean within a region that has a basic Mediterranean climate--that is, most of the rain comes in the winter months. This forest is a relict of more widespread rainforests that once covered much of the West. For most of the region the months of June, July and August (at a minimum) are virtually without rainfall. Being near the ocean, however, the coastal redwood forest is regularly covered by fog during the summer months. Much of the effective precipitation in this redwood / fog belt comes from the phenomena of fog drip--the ability of the redwood trees to capture fog from the air and transport it to the ground where it is utilized by many other life forms. When forests of the region are overcut they lose much of their capacity to capture moisture from fog during the hot, dry months of summer. This is in addition to the well-documented ecological effects of deforestation common to most forested regions (soil exposure, accelerated erosion, sedimentation of streams, etc.). Overall, with unstable soils and relictual forests with unique flora and fauna, the Coastal Forest of the Klamath ecoregion is highly sensitive to land use impacts. The industrial timberlands have been severely overcut and the watersheds degraded.

California Chaparral. California chaparral is composed mainly of evergreen woody shrubs, and it forms extensive shrublands that occupy most of the hills and lower mountain slopes of California. It is adapted to drought and fire, passing endlessly through cycles of burning and regrowth. Even though chaparral has no commercial value, it forms the most highly valued watershed cover of any vegetation in the state. "Chaparral" is a word of Spanish origin (chaparro) that originally denoted a thicket of shrubby evergreen oaks. The geographic factors that influence chaparral development are slope, aspect, coastal-desert exposure, elevation, substrate, and fire. The dominant woody genera of the California chaparral, such as Adenostoma (chamise), Arctostaphylos (manzanita), Ceonothus (ceonothus), Heteromeles (toyon), and Rhus (sugar bush), are absent from other regions having a Mediterranean type climate. Since this common type is favored by fire suppression, it has probably increased in recent decades, and the proportion of its acreage in older successional stages has also increased.

Mixed Evergreen Forest. The term "mixed evergreen forest" describes a characteristic set of coastal California mountain communities. In the Klamath Ecoregion consists of Douglas fir-hardwood forests in the Klamath Mountains and North Coast Ranges. Douglas fir-hardwood forests form part of an extensive mosaic with northern oak woodland and coastal prairie in the southern and coastal portions of the region. As in the Klamath mountains, these forests show various combinations of Douglas fir, tanoak, and madrone dominance on deeper, well-drained soils. In southeastern portions of Humboldt and Mendocino Counties, ponderosa pine becomes a major codominant in forests and woodlands. At higher elevations, limber pine is of secondary importance, and to the south, coast live oak becomes an increasingly common associate.

In the Klamath Ecoregion, the mixed evergreen forest has been subjected to the same pressures from logging as the coastal forests with similar, but not identical results. As with the coastal forests, most of the old growth forest is gone and only a few remnant patches remain. However, since the logging has been primarily for the conifer species, the result has been that many acres of mixed conifer/hardwood forest has been converted into forests dominated by hardwoods.

stands are also harvested for firewood and cogeneration fuel.

Vernal Pools. Vernal pools are ephemeral wetlands forming in shallow depressions underlain by a substrate near the surface that restricts the percolation of water. They are characterized by a barrier to overland flow that causes water to collect and pond. These depressions fill with rainwater and runoff from adjacent areas during the winter and may remain inundated until spring or early summer. As these depressions dry up in the spring, various annual plant species flower, often forming conspicuous concentric rings of showy colors. Pool vegetation is azonal, with edaphic factors more important than the regional climate which affects the surrounding vegetation. There are three general types of vernal pools: valley pools, terrace pools, and pools of volcanic areas. This remnant habitat type is concentrated within the Santa Rosa Plain, but vernal pools are found throughout the Klamath Ecoregion. Both agricultural conversion and urban/suburban development have caused substantial loss of these habitats. Endangered species protection and land-management planning have slowed the pace of habitat loss, but pressure for agricultural conversion and/or development is still strong.

Great Basin Desert including Sagebrush Steppe. The Great Basin desert is the most extensive desert in the U.S., stretching from southeastern Oregon and Wyoming, south to northern New Mexico, and west into extreme eastern California. Within the Klamath Ecoregion, Great Basin desert vegetation is found on the Modoc Plateau region of the upper Klamath River basin. Topography of the Great Basin Desert varies but generally consists of wide valley floors between 4,000 and 6,000 feet interrupted by mountains. Temperatures drop much lower than any other U.S. desert, with a short frost-free season and very cold winters, and precipitation ranges from 4 to 12 inches. Two major vegetation communities occur within this desert, both of which are structurally and floristically simple: (1) sagebrush, and (2) shadscale or saltbush associations. Species with evolutionary affinities to warmer climates such as rabbitbrush and blackbrush are also present in the Great Basin Desert. The sagebrush steppe consists of a series of generally treeless, shrub-dominated communities with a ground layer characterized by perennial bunch grasses including bluebunch wheatgrass and Idaho fescue. Within this type, many of the better sites on deeper soils have been converted to agricultural uses, particularly where irrigation water was present. Both livestock grazing and fire suppression have also played a role in converting the vegetation of this region. Overgrazing by livestock over time can result in the removal of the ground layer of perennial grasses or conversion of this layer into annual grasses and forbs. By contrast fire tends to set back the shrub layer while only temporarily setting back perennial grasses and forbs. Periodic fires in the past tended to produce patches of grassland within the shrubland. Fire suppression thus has tended to reduce the density of grassland patches. When the two (livestock grazing and fire suppression) are combined, this effect may be even more pronounced, because the removal of perennial grasses, retards the capability of the vegetation to carry fire. In some grassland areas, overgrazing has resulted in an introduced annual grass, cheatgrass, to dominate sites. Since this grass is well adapted to fire (it both spreads fire easily and is well adapted to reproduce after fire), on many sites it becomes dominant and it is difficult to reestablish the native vegetation. A variety of other invasive annual forb species have invaded Great Basin grasslands that are subject to overgrazing.

Montane and Subalpine Vegetation of the Klamath Mountains. The Klamath montane forests form a series of more or less discrete, island-like patches within a matrix of low-elevation forests and woodlands in northwestern California and southwestern Oregon. Klamath montane forests grow mostly above low-elevation coniferous forests rather than chaparral, woodlands, or grasslands. Dominant species, such as Douglas fir, ponderosa pine, and sugar pine are typical of low as well as montane elevations. The habitat requirements, competitive ability, fire resistance, and colonizing ability of individual conifer species have determined their ecological positions in elevational zones and habitats throughout the montane forests of the Klamath region. Decades of timber harvest have reduced the amounts of old-growth montane forests; most significant remnants are now in semi-protected reserves on public lands. Fire suppression has resulted in increased stand density, high mortality on some sites, and increased likelihood of stand-replacing fires. The extent of noncommercial timber species near timberline remains largely unchanged.

Transmontane Coniferous Vegetation. The transmontane region of California traditionally includes the portions of the state lying east of the main crests of the Cascade-Sierra axis and of the southern ranges forming the divide between coastal and desert drainages. Within the Klamath Ecoregion, this type is restricted to the Modoc Plateau. Three broad categories of coniferous vegetation occur primarily in the transmontane region of California: northern juniper woodlands, pinon and juniper woodlands, and montane coniferous forests. The northern juniper woodland described by Munz and Keck (1949) is here interpreted to include two phases: a western juniper woodland in open, rolling country and a mountain juniper on ridges and mountain slopes. The western juniper woodland is characterized by open stands or scattered trees of western juniper. The understory may have a grassy understory, particularly where trees are close together, or they may have a shrub understory in more open stands. Understory shrubs, or interspersed stands of low shrubs, are primarily big (Great Basin) sagebrush on deep soils or well-drained slopes, and black sagebrush on heavy soils and rocky substrates. The mountain juniper woodland is characterized by scattered trees of western juniper, commonly in association with Jeffry pine, currleaf mountainmahogany, bitterbrush, and big sagebrush. Juniper woodlands represent the westernmost expression of widespread pinon/juniper vegetation types occurring in the Great Basin and Colorado Plateau regions. Fire suppression together with livestock grazing may be causing a continued expansion of juniper woodland in the extreme northeastern portion of the ecoregion, at the expense of shrubland and grassland.

Oak Woodland. The oak woodland has little floristic unity except the ubiquitous annuals in its ground cover. Species from adjacent grassland, chaparral, and forest communities associate with the "woodland" trees over a wide range physiographical and climatic situations. Open stands of deciduous "white oaks" characterize vast tracts of oak woodland, but evergreen "black oaks" are often present and sometimes dominant. Also, one or more species of pine may be scattered among the oaks. On the ground, the oak woodland has a significant grassland cover under and between the trees. Different oak species are involved regionally. Oak woodlands remain fairly stable, except in limited areas near urban regions, or where access for firewood cutting or cogeneration fuel concentrate impacts.

Tule Marshes and Wetlands. Wetlands are characterized by hydric soils and water-loving plants. Of the many diverse types of wetlands, marshes are the most widely distributed and the best-known form. They are dominated by emergent plants such as cattail, bulrushes, sedges, and water-tolerant grasses. Marshes often are complete entities, found in shallow basins. The term may also be used for any emergent hydrophyte community. Water is the driving force in determining wetland type and habitat quality. Water permanency and associated vegetation are key factors in classifying wetlands. Because water cycles are variable, marshes are rarely constant. These fluctuations induce "boom and bust" in wildlife numbers, but are essential to nutrient recycling. Although increased regulation has slowed the rate of decline, loss of freshwater wetlands continues on a localized level due to urban development and intensive agricultural practices.

Vegetation Communities

At a more detailed level, vegetation can be described in terms of plant communities. A plant community is "all of the plant species found growing together at one time in a given habitat or region." In order to classify and map plant communities, plant ecologists usually label them in terms of: (a) one or more dominant or codominant plants (e.g., beach pine forest); (b) the substrate, landform, or location (e.g., coastal dunes, bald hills prairie); or (c) combinations of the two (e.g., upland Douglas-fir forest; northern interior cypress forest). The actual descriptions of the type used in classification and mapping are usually based upon a few dominant and co-dominant plant species.

A system for classification at this level has been developed for California and it describes the vegetation of California in terms of 375 "natural communities." Natural communities as thus described are "tangible units that can be counted, protected, and managed." They can also be mapped.

The plant communities within the ecoregion and their acreage within Northwestern California are listed in Appendix I. Most of the California portion of the ecoregion has been mapped at this level by Thorne (1997) and his work provides some indication of the relative percentages of the different community types in the region.

Vegetation Series

Vegetation can be described in more detail at the "series" level. A vegetation series is usually described in terms of one or more dominant plants. Thus plant series are usually relatively easy to recognize qualitatively in the field, although they may be very patchy. For a more complete description of the series level of description and its utility refer to Sawyer and Keeler-Wolf (1995:1-18). The series found within the ecoregion are listed in Appendix II. Note that some series descriptions correspond to Holland’s plant community descriptions, while many others do not. They are cross referenced to the extent possible in Appendices I and II.

The relative rarity of various plant series and communities is described and discussed later in this volume as well as in volume II. In particular, emphasis is placed upon plant communities that have become rare or degraded as a result of human activity. Note, however, that the ranking system used in Appendix II does not distinguish between communities that are rare as a result of human activities and those that are rare for other reasons.

Vertebrate Fauna

Fish and wildlife species found within the Klamath Ecoregion are listed in Appendix III. The vertebrate fauna of the region is thoroughly described in many books on the statewide, regional, and local level and we make no attempt here to summarize or abstract the wealth of information they contain.

In general, the vertebrate fauna is characterized by a high species richness and a high degree of endemism for most groups. At least 77 fish species have been reported from the region, of which 24 are nonnative introduced species that have become established. Fish species from the region fall into three main groups: (1) Upper Klamath River species, (2)Lower Klamath River species, and (3) species from the other coastal rivers from the Smith River south to San Francisco Bay (Appendix II -Table AII-1). Both the coastal rivers and the lower Klamath support twelve species of native anadromous fish, including six species of salmon and steelhead; the upper Klamath formerly supported anadromous salmonids prior to being dammed. The fish fauna of the upper Klamath Basin contains several species endemic to the region including the Klamath largescale sucker, the Lost River sucker, and the shortnose sucker. The fish fauna of the upper and lower Klamath River are relatively distinct reflecting the relatively recent connection between the two systems in geologic time.

The region supports 24 species of amphibians and 24 species of reptiles. Several of the amphibian species are endemic to the region including the red-bellied newt and Dunn’s salamander. The reptile fauna is more cosmopolitan with only one species, the northwestern garter snake, endemic to the region. We are aware of only one species of amphibian or reptile, the bullfrog (Rana catesbeiana), that has been introduced and become widely established within the region.

The region supports over 270 bird species, partially due to the richness and diversity of the habitats present but also because of its location on major migratory routes. The marshes and wetlands of the upper Klamath Basin are a major stopping point for waterfowl and shorebirds migrating along the Pacific flyway. Many other species move along the coast taking advantages of the beach habitat and the lagoons and estuaries for loafing, feeding, and roosting. Finally, birds migrating up and down the coastal mountains add to the bird diversity. Lastly many birds migrating up and down the Sierra Nevada and Cascades will cross the upper Klamath Basin. Many of these birds are neotropical migrants--species in which some populations migrate north from the tropical regions of North and South America. In addition to these migrants, there is a diversity of resident species as well as species such as band-tailed pigeons that tend to move around within the region. There are no birds endemic to the region. Six species of birds, the European starling (Sturnus vulgaris), the English or house sparrow (Passer domesticus), rock dove (Columba livia), wild turkey (Meleagris gallopavo), chukar (Alectoris chukar), and ring-necked pheasant (Phasianus colchicus) have been introduced and become widely established.

The mammalian fauna similarly contains few endemic species. The only truly endemic mammal is the redwood or yellow-cheeked chipmunk (Tamias ochrogenys) which is found in coastal Sonoma and Mendocino Counties. There are seven species of nonnative mammals that have been introduced and become widely distributed, Virginia opossum (Didelphis virginiana), black rat (Rattus rattus), Norway rat (Rattus norvegicus), house mouse (Mus musculus), wild pig (Sus scrofa), fallow deer (Cervus dama), and feral goat (Capra hircus).

Invertebrate Fauna

Much less is known about the invertebrate fauna of the region, and in many cases, even the description of the species present is incomplete. While it is widely believed that invertebrates are extremely critical in functioning of ecosystems except in the case of endangered species, most efforts at invertebrate conservation rely upon habitat conservation. The assumption of such an approach is that if intact habitats that represent the full spectrum of types present in a region are left intact, then most invertebrate species will survive in such areas.

Wildlife Habitat

Since inventory or census of wildlife populations are time-consuming and expensive, most analyses of the wildlife resources of an area and/or their status rely upon some evaluation of the wildlife habitats present and their condition.

In California, a system called the California Wildlife Habitat Relationships (WHR) System has been developed. The habitat component of the system is composed of a habitat classification and vegetation description of the wildlife habitats in California and a computer data base that includes species-habitat relationships models. Wildlife habitats within the Klamath Ecoregion according to the California Wildlife Habitat Relationship System are shown in Table I-3.

Note that the wildlife habitats listed in Table I-3 are for California; there is not a comparable system for Oregon. However, we believe that all habitats within the upper Klamath Basin (the only portion of the ecoregion in Oregon) are covered by this classification. Note also, that the California Wildlife Habitat Relationship System is only for terrestrial vertebrates. There is no comparable system of classification of aquatic habitats and/or fish habitat relationships, much less any coverage of invertebrates and their habitats. Since wildlife species respond to vegetation structure as much as they respond to species composition, and because vegetation structure is correlated with the successional stage of the vegetation, wildlife habitat evaluation systems such as WHR usually include successional stage as one of the predictors. Thus, wildlife habitat maps such as in Figure I-11, show not only the vegetation type that is present, but also how much of it is in various seral stages. Thus, one can see, for example, how much late seral or old-growth habitat is left in an area relative to the total amount of habitat of that type of vegetation.

The question of how much habitat of each of these types is present in the ecoregion requires some modification of the system. The reason for this is that the only practical way of obtaining such estimates at the present time is through the use of remote sensing. These habitat types have been mapped from aerial photography using 1993 Landsat Thematic Mapper images by Dr. Larry Fox and his students and coworkers at Humboldt State University. The wildlife habitat types that can be distinguished from Landsat are shown in Table I-4.

Figure I-11. Wildlife habitat types from Landsat thematic mapper ("Fox habitat types").

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Table I-4. Vegetation Types Determined from Landsat Thematic Mapper Classified Into Wildlife Habitat Relationship (WHR) Classes.

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GENERAL TREE TYPES

needle-leaf)

GENERAL SHRUB TYPES

GENERAL HERBACEOUS TYPES

GENERAL BARREN TYPES

GENERAL AQUATIC TYPE

First Nations

Native Americans have occupied the Klamath Ecoregion for at least 10,000 years. The native Americans of the region are from six separate linguistic groups (Figure I-12), thus suggesting that their origins were quite diverse. They lived in scattered temporary and permanent villages throughout the area. As best we understand it Native Americans associated with their villages and clans more than with their "tribe" as described by anthropologists of European origin. The anthropologists who studied native Americans, as well as the government officials attempting to deal with them, tried to categorize Indians into discrete tribes. An anthropological map of the Native American tribes of northern California is shown in Figure I-13.

Within this region the Native Americans had developed complex and diverse cultures, well-adapted to the localized landscape conditions and use of native plant and animal materials. Native Americans depended heavily upon salmon (in most of the region), suckers (in Upper Klamath Basin), shellfish (along coast), acorns (drier portions of ecoregion), and deer and elk (throughout the ecoregion). In addition, the native cultures made extensive use of hundreds of other species for food, housing, boat building, basketry, medicine, ceremony, and many other uses.

The native people maintained and subtly manipulated the landscape in a manner that has not been fully appreciated by non-Indians until recently through practices such as burning and seeding. Blackburn and Anderson (1993b) describe this process:

The most powerful, effective and widespread technique used was fire. However, many other techniques such as complex harvesting strategies were employed.

Figure I-12. Linguistic stocks of Native Americans of the Klamath Ecoregion.

Figure I-13. Tribes of Native Americans within the California portion of the Klamath Ecoregion.

Contact with European Culture (1700-1900)

The history of native American treatment upon contact with European culture mirrored that interaction in the rest of North America. Although the specifics differ, the various tribes were subjected to unkept promises, random and planned violence, and general mistreatment at the hands of government and citizen alike.

In 1851 a United States Indian Agent, Redick McKee embarked from Sonoma on a five hundred-mile journey that encompassed most of the ecoregion--at least the portion in California. McKee gathered native Americans together and negotiated a series of treaties that would have forever guaranteed them a few prime sites in the region such as the lower Eel River, Hoopa Valley, Scott Valley, and the Klamath-Trinity region. As token an effort as it was--these treaties were never ratified by Congress.

The persecution of the native Americans continued for many years--with Indians being rounded up onto reservations, shipped to remote locations (e.g., the Modocs were sent to Oklahoma), and generally stripped of resources, power, and pride.

Early European / American Settlement (1700-1900)

The Klamath Ecoregion is somewhat unique in that the European invasions of the last 500 years came from quite different directions: the Russians moving across the Bering Strait and down the coast, the Spanish working their way up California from Mexico, and the Americans moving across the continent from the east.

The Russians were the first non-Indians to arrive in the region. They were primarily fur trappers and traders who had worked their way down the coast from Alaska. They were not, for the most part, interested in setting up permanent Russian settlements or colonies, i.e., bringing wives and families from Russia. Rather they set up trading posts, primarily along the coast. One of the first, Fort Ross, was established in 1812. Of all the immigrants of this period, however, the Russians probably left the least mark on the land. The Russians gradually withdrew from the Northwest, and with the purchase of Alaska from Russia by the United States in 1867 the Russians essentially ceded any interest in establishing settlements in North America. Not having established any permanent settlements in the Klamath Ecoregion, the Russians left only a few artifacts as evidence of their activities during this period.

The Spaniards and later Mexicans were to leave a more permanent mark on the ecoregion. Juan Rodriguez Cabrillo sailed north from Mexico in 1542 as far north as Point Mendocino and is widely credited as being the first European explorer to reach California. It was another 200 years, however, before Spanish and Mexican settlers began to enter California. In 1769 a small band of Spanish and Indians under the leadership of Don Gaspar de Portola journeyed from Baja California and established the first of many missions in San Diego. The following years were to see missions established further north eventually reaching Sonoma County within the ecoregion.

The Spanish influence during this period was largely limited to the southern portion of the ecoregion. Mission San Francisco Solano, commonly called Mission Sonoma was established in 1823 in the Sonoma Valley near what is now the city of Santa Rosa. This was the northernmost mission in California and for the most part marked the extent of Spanish / Mexican settlement during this period.

The "Americans" were the last to arrive in the region. The first Americans (from the United States) to explore the region were the fur trappers who arrived after 1800. In 1828, Jedediah Smith, an American fur trapper and shortly thereafter the Hudson Bay Company ventured into the region to trade with the Indians. However, few American settlements were established in the region until the massive migration that began around 1830. These settlers settled primarily in the more open valleys along the Russian River in what is now Sonoma and Mendocino Counties, as well as the upper reaches of the Klamath Basin along the Scott, Shasta, Williamson and Lost Rivers, where land was more suitable for agriculture. Other settlements developed along the coast where towns developed around the timber industry which could supply lumber via ship to the rapidly expanding settlements to the south, particularly San Francisco. The gold rush of 1850 brought a tremendous influx of gold seekers to California, initially to the Sierra Nevada, the site of the first major gold discovery. However, gold was discovered in the Klamath Basin in 1852 and this brought a wave of miners to this region. Overall, the period from 1850-1900 saw a tremendous influx of American settlers to the region, although it was for the most part it was concentrated on the coast and in the valleys suitable for agriculture.

During this period the major industries that were to dominate the ecoregion to this day were first established--ranching, mining, timber, fishing, and agriculture. These industries were, for the most part, widely scattered and of low intensity--resulting in limited or very localized impact upon the natural resources of the region. The exception, during this period was mining--in particular hydraulic mining which was in common use by the 1870s.

Twentieth Century Development (1900-1950)

The period from 1900 to 1950 in the Klamath Ecoregion was a period in which the basic patterns of immigration, settlement, human infrastructure and industry were continued and expanded. At the turn of the century, most cities and towns of the ecoregion were semi-isolated from each other. This changed dramatically with the widespread increase in motorized travel beginning around 1910. In 1917 the "Redwood Highway" was completed linking the coastal cities of Crescent City, Arcata and Eureka with those to the south such as Ukiah and Santa Rosa. This highway was good for commerce--but conservationists recognized right away that it would dramatically increase the amount of logging--particularly of the redwood forests. Highway connections between the coast and the upper Klamath Basin remained primitive into the 1950s. With more people the demands and stresses upon natural resources increased. Timber harvest increased--particularly within the coastal redwood region. (Concerned with the imminent demise of the redwoods the "Save the Redwood League" was incorporated in 1920). However, elsewhere the combination of inaccessibility and low demand discouraged widespread exploitation of forests further inland.

During this period large scale water diversion from most of the rivers of the ecoregion was initiated. During the earlier period, prior to 1910, small water impounding dams had been built, but these were mostly small, located on tributaries, and often impermanent--being washed out with larger floods. (A wooden dam was built on the upper Klamath River at Klamathon in about 1889 for a large lumber mill there, but it was destroyed by fire in 1902.) By the early 1900s both the technology and infrastructure were available for bigger dams. So too, was the demand--at first for water then later for water and power. On the Klamath River, Copco dam (Copco #1) was completed in 1917.

It was during this period, however, that the so-called "reclamation" of the wetlands of the upper Klamath Basin was initiated. Beginning in 1905 the Bureau of Reclamation began the "Klamath Project" which ultimately resulted in draining 65 to 80% of the natural wetlands of the area and converting them into agricultural land. At the same time water was diverted to these and other drylands for agricultural purposes.

Recent Development (1950-1996)

The changes of the latter half of the twentieth century represent a continuation of many earlier trends--but more importantly an acceleration of many of the trends. Logging, once largely confined to the redwood forests was expanded to the higher elevation douglas fir and ponderosa pine forests. This post World War II boom in forestry was driven by demand for lumber for new housing. At the same time, it was facilitated by newer technology--namely improved gasoline powered chainsaws and crawler tractors for skidding logs.

Similar patterns occurred in other industries. Improved technology for fishing allowed more efficient and larger ocean harvest of salmon. And larger dams were now being built (Iron Gate completed in 1962; Trinity and Lewiston Dams in 1964). Most significantly, Trinity and Lewiston Dams, provided for massive water diversion from the Klamath River Basin into the Sacramento River where the water is used for agriculture. Other dams on the Eel and Russian rivers as well as many smaller streams provided for diversions within the ecoregion.

Human population increased steadily throughout most of the ecoregion, however, the most dramatic increase came in the southern end of the ecoregion in Sonoma County. The population of Sonoma County almost doubled from 1970 to 1990 going from 205,000 to 388,000. Thus, in 1990 based upon County population census data, more than one-half of the population of the ecoregion is found in the southern 10% of the region.

First Nations

The native American population has been drastically reduced in numbers and distribution. However, 34 tribes still reside within the ecoregion (Table I-8) of which 28 are Federally recognized. They are scattered on rancherias and reservations throughout the ecoregion as shown in Figure I-14.

Having had their land base drastically shrunk, these native Americans are struggling to adjust, socially and economically, to the new conditions in the ecoregion. Those tribes that have had the resources to pursue legal strategies for recovering some of their rights have had some success. And some of these legal decisions may have region-wide implications. In particular, the Hoopa and Yurok tribes have successfully sued to have water returned to the Trinity River adequate to support the traditional salmon fishery there. Implementation of this decision will result in less water diversion out of the ecoregion and a general improvement in the flow and water quality in the Trinity and lower mainstem Klamath. Similarly, the Klamath Tribes have sued to provide protection for the Short-nose and Lost River suckers, two endemic fish that provided traditional sustenance for the tribes and are now federally endangered, largely as a result of water diversion and associated agricultural activities.

Figure I-14. Location of rancherias and reservations of Indian tribes from the Klamath Ecoregion.

Demographics

Population densities for the ecoregion are shown in Figure I-15. Most of the population is concentrated in the southern end of the ecoregion, with more than half of the total population of the region found in Sonoma County (Table I-9). Sonoma County is also the fastest growing area within the ecoregion, having doubled in population from 1980 to 1990.

Figure I-15. Human population densities for the Klamath Ecoregion.

Socio-Economic Status of Residents

Statistical measures are weak indicators of "socio-economic status" or the more nebulous "quality-of-life." However, bottom line measures such as income levels, unemployment rates, and level of education as shown in Tables I-10 through I-12 provide some indication of what is happening in a community. The income levels for most of the counties are quite comparable, with the noticeable exception of Sonoma County which has both higher household and per capita income. This is most likely a result of the types of jobs that are available in the more urban Sonoma County as opposed to the more rural counties to the north, as the levels of educational attainment shown in Table I-11are similar.

One of the keystone elements of modern thinking in ecology and conservation is to give equal attention to ecological processes rather just to composition and structure of ecosystems. In this section, we describe briefly five of the critical or keystone ecological processes occurring at the ecosystem level. Ecosystems are complex systems with millions of ecological processes being played out in diverse and subtle ways at different spatial and temporal scales. Thus, any description of ecological processes must be selective. We emphasize here processes that are: (1) understood to at least some degree by humans and science, (2) known to be affected by human activities, or (3) unique to the Klamath Ecoregion. The latter would include processes such as "fog precipitation" which is not found in most inland ecoregions.

Energy Flow

The flow of energy through a system is so fundamental to maintaining its function that it is often ignored when considering effects on an ecosystem. Virtually all of the useful energy in most terrestrial ecosystems comes initially from the sun. This is true in the Klamath Ecoregion as there are no major net imports of energy other than from the sun. However, within the ecoregion and its components, distribution of energy is quite uneven. Thus, the flows between these components are quite important. Solar energy is captured by plants through the process of photosynthesis and excess energy is stored, primarily in organic (carbon based) compounds such as carbohydrate and cellulose. This pool then becomes the source of energy for all other living organisms in the ecosystem. For example, dead and down woody material and litter is the primary energy source for soil microorganisms that keep soil processes active. Similarly, most of the energy for organisms that live in aquatic habitats comes from the uplands in the form of leaves, litter, and trees that fall into streams and lakes.

Biogeochemical / Nutrient Cycles

Cycling of chemicals or nutrients such as nitrogen, phosphorus, and sulfur is equally important in ecosystems, since these chemicals are not evenly distributed in the ecosystem. Two of the most important nutrients for ecological systems are nitrogen and phosphorus--and they serve well to illustrate differences in sources and sinks for such elements.

The major source of nitrogen in the global ecosystem is in the atmosphere. And the only way in which nitrogen is moved from the atmosphere to earth is through the action of nitrogen fixing bacteria and similar microorganisms--many of which live in symbiotic relationships on the roots of plants. Legumes are best known for their nitrogen fixing association but other plants such as alders (Alnus spp.), ceanothus (Ceanothus), and bitterbrush (Purshia), also harbor nitrogen fixers. As all life forms require nitrogen, ecosystem function is ultimately dependent upon the action of these nitrogen fixers, as nitrogen is constantly being released back into the atmosphere. Thus without constant nitrogen fixing, ecosystems would be subject to a net loss of nitrogen and life within them would eventually die out.

Within the ecosystem, nitrogen is quite unevenly distributed. Nitrogen is often the nutrient most limiting for plant growth and most of the available nitrogen is stored in the top few inches of the soil. Similarly slight changes in nitrogen content of plant parts may determine whether such forage is adequate nutritionally for herbivores such as elk or antelope.

In contrast to nitrogen, the ultimate source of most phosphorus is in the rocks and soil. In spite of this, phosphorus can often be limiting in soils and plants. On the other hand, accelerated erosion can often put large amounts of soluble phosphorus into streams and lakes that have not evolved with such inputs. This in turn results in algal blooms, reduction in available oxygen, and other effects that are generally detrimental to native species, as is happening in Upper Klamath Lake. As with other nutrients, wetlands play a key role in buffering the aquatic ecosystem from such pulses of phosphorus.

A system like the Klamath Ecoregion is not, of course, a closed one and there are some net imports and exports of nutrients. Of particular importance is the net nutrient import as a result of spawning runs of anadromous fishes. It is well known that many species such as bears and eagles take advantage of these nutrient flows. At a more general level, however, these runs once represented a net import of roughly 1 pound per acre of "fish fertilizer" per acre for the entire ecosystem. This amount may not be significant in a given year--but over centuries may be of some significance. Furthermore, the distribution of such fertilizer is far from uniform--with some areas receiving more than their share of "fertilizer."

Soil Formation / Soil Erosion Dynamics

Conservation of topsoil is or should be the most basic and fundamental goal of any holistic or ecosystem level conservation effort. Topsoil has been likened to the balance wheel of the ecosystem. It has also been called the placenta of life on earth. It is critical in the hydrological cycle as will be discussed. For these reasons, topsoil has been likened to capital where trees, crops, forage and wildlife are the profit. And of course the cardinal rule of capitalism is not to spend the capital and maybe even put some profit back into the capital account. Yet soil conservation is often neglected or poorly integrated into management or conservation plans and programs.

To understand and plan for soil conservation, one must recognize that topsoil present represents some sort of rough equilibrium between soil loss and soil development. A goal of zero soil loss is unrealistic; some movement or "loss" of soil through erosion, mass slumping, and so on is a normal ecological process upon which many species are dependent. For example, many riparian wetlands are continuously formed and/or replenished by suspended sediments moved downstream during periods of heavy flooding. Similarly, many estuarine plants and animals are adapted to capturing and stabilizing silt from upstream.

However, a goal of no "net loss" of soil or topsoil is fundamental to any program of ecosystem conservation or management. This implies that the rate of soil loss must not exceed the rate of soil development. For soils to develop, the rate of soil formation must exceed the rate of loss. Rates of soil erosion are known in a general way by soil scientists and are expressed as an erodability factor in soil surveys. The implicit assumption is that under normal conditions rates of soil development exceed that rate. Any evidence that rates of soil loss are exceeding this rate suggests that there is net soil loss and thus ecosystem degradation.

Background (historical) rates of soil erosion have been determined for certain portions of the ecoregion and are shown in Table I-13.

Some portions of the ecoregion are inherently more susceptible to erosion and this affects or should affect management options. In general terms, the soils of the Coast Ranges, being derived from unconsolidated Franciscan sedimentary deposits, are most erodable, and those of the Modoc Plateau are least erodable.

Hydrologic Cycle

The hydrology of the Klamath Ecoregion has been outlined earlier. The general pattern of the hydrologic cycle varies little within the region. Moisture from the ocean is moved inland where it is deposited in the form of fog, rain, or snow depending upon the portion of the ecoregion. From there it is used by plants or evaporated (evapotranspiration) or it moves back toward the ocean.

Portions of it may infiltrate the ground and move as groundwater or can run across the surface of the land. Eventually it makes it way into small streams and eventually back to the sea. Although the general pattern applies across the region--the specifics may be quite different. For example, most of the summer moisture in coastal regions comes in the form of fog--whereas in the Klamath Mountains it comes in the form of summer thunderstorms.

During this cycle, there are several critical points where the hydrologic cycle may be quite sensitive to changes in the environment. For example, the point where rain comes in contact with the land surface is quite sensitive to changes in that surface. If the surface is covered with diverse vegetation and deep porous soils then most of the precipitation will eventually infiltrate into the ground and become groundwater. On the other hand, if vegetation is sparse or the soils are compacted then much more of the precipitation will evaporate or run off overground taking soil with it.

A list of critical points in the hydrologic cycle for particular portions of the ecoregion is shown in Table I-14.

Disturbance Regimes / Succession

Major natural (non-human) disturbance regimes within the Klamath Ecoregion include fire, wind, and flooding. Evidence from upland areas of the Klamath Mountains suggest that fire is the most common disturbance in forest stands with wind being next most important. Fire accounted for over 80 percent of the disturbances with wind accounting for roughly another 10 percent.

The importance of fires as agents of disturbance has been recognized for many years. However, historic fire patterns have only been characterized for a few vegetation types within the ecoregion. Historic fire patterns can be characterized by "mean fire interval" (equivalent to "mean fire return interval") and by "fire frequency". The former is the arithmetic average of all fire intervals in a designated area during a designated time period. "Fire frequency" is the number of fires per unit time in some designated area. Both of these measures are scale dependent in that the number will vary depending upon the size of the "designated area". Thus, comparisons of such measures of fire history from different studies can be misleading. Nevertheless, they do provide some utility in comparing historic fire patterns among different sites and vegetation types and in assessing how humans have changed historic fire patterns. Reported fire return intervals for forest types found within the Klamath Ecoregion range from 15 years for Ponderosa Pine to 500 years for coastal redwood forest.

Along rivers, flooding can also be an important disturbance regime--and calculations provided by Rantz (1964) allow calculation of frequency of flood events of a given magnitude for any given river in the ecoregion. The greatest known floods in the ecoregion are those of the winter of 1861-62. The peak discharge for the Klamath River in December 1961 was computed as 450,000 cfs compared to a mean annual flood of 152,000 cfs. The floods of 1955 were of comparable magnitude, however, with a peak discharge of 425,000 cfs recorded for the Klamath River on December 22, 1955.

Succession refers to the change in plant communities following natural or human disturbance. The pathways of succession, i.e., the plant communities and their composition and their pattern of replacement are more or less predictable and have been described for many vegetation types. For example, brush fields that have been burned will first be invaded by annual grasses and forbs, then by perennial grasses and forbs, then eventually by shrub species that will come to dominate the site. Actual shrub species present will vary depending upon the characteristics of the site such as soils, slope, elevation and so on. It will also vary depending upon the type and severity of the disturbance. For example, some shrubs will sprout quickly from live roots after light fires. In such circumstances they will return to dominate the site much faster than when the fire is so hot that the roots are killed.

Succession is thus thought to be more or less predictable. However, current thinking in both forestry and range management is suggesting that if disturbances are beyond a certain threshold, the plant communities will not necessarily return to their original state. This newer understanding of succession has important implications with regard to how biotic communities respond to human activities. If true, it suggests that some human activities may cause irreversible effects on plant communities or effects that are reversible only over long (geologic) time periods or by investment of large amounts of human energy and resources for restoration.

In this section we describe how humans have modified the ecosystem. In the first section we describe the major activities that have impacted the system such as timber harvest and water diversion. In the second section, we describe effects these activities have had on the ecosystem or ecosystem level functions. Finally, in the third section we describe how these activities have affected wild species or species groups.

Activities

We describe here major human activities affecting the ecosystem along with some of the obvious effects on ecological function. Most human activities involve a complex suite of actions. Thus, for example, under "timber harvesting" we include not only the cutting and removal of trees but also road building, fire suppression, herbicide application, and monoculture--all activities that are typically carried out as part of a timber harvest industry.

Timber Harvesting. Decades of timber harvesting have impacted the carrying capacity of the natural resources of the ecoregion. Timber harvest and associated road building has exposed highly erodible soils leading to siltation of streams and rivers. Such siltation degrades aquatic habitat and diminishes spawning of fish and other aquatic functions. Over harvesting of timber has also reduced and fragmented old growth that is needed by many wildlife species. Silvicultural practices, including herbicide application and single species reforestation, have changed species composition and reduced diversity. Lastly, suppression of natural wildfires has resulted in high fuel loading with resultant change in fire regimes tending toward fewer but hotter fires.

Dams and other Water Diversions. Water diversions reduce habitat for aquatic species by reducing discharge in rivers and streams. Changes in natural discharge patterns reduce or eliminate channel maintenance flows and impact water quality, particularly during low flow periods. Dams hinder or prevent fish passage to important habitats. This has been a particular problem for anadromous salmonids and other fish in the ecoregion. Major diversions on the Klamath, Trinity, Russian, and Eel Rivers have caused degradation of much fish habitat and prevented access to hundreds of miles of stream habitat. Large storage reservoirs have also inundated important upland habitats.

Mining. Mining activities in the ecoregion started in the mid 1800s with large areas affected by gold prospecting and extraction. Many of these areas have not been reclaimed and they continue to contribute to sedimentation and pollution of streams and rivers. Current suction mining not only can cause sedimentation but may also impact fish directly.

Livestock Grazing. Poorly managed livestock grazing: (1) reduces upland and riparian vegetation for waterfowl, upland game and song bird nesting cover; (2) changes the structure and diversity of vegetative communities; (3) physically alters stream systems to the detriment of fish populations; (4) increases competition with native wildlife; and (5) contributes to loss of wetlands.

Agriculture. Agricultural activities affect ecosystem structure and function in four primary ways: (1) direct conversion of habitat (from wild or semi-wild land to monoculture); (2) diversion and use of water; (3) soil loss and siltation of waterways; and (4) use of pesticides, fertilizers and other chemicals that contaminate soil, air and water. Of these four, direct conversion of land is certainly among the most critical impacts, yet it is often one of the least observable, since many of the conversions have been in existence for a long time and/or are occurring slowly. For example, conversion of wetland to farmland has resulted in a loss of over 75% of historic wetland areas in the upper Klamath Basin alone. Yet, even to a long time resident, little change is evident from day to day. Irrigation projects throughout the ecoregion have resulted in the construction of hundreds of miles of canals, drains, ditches, and dikes. Siltation reduces productivity of adjacent marshes and topsoil loss is significant on fallowed farmland. Water removed from reservoirs is used for farming activities with resultant reduction in water quality and quantity in the river systems of the ecoregion. Finally, a wide variety of pesticides, fertilizers, and other chemical contaminants are used in agriculture. These chemicals end up in air, in waters, and in soils with many deleterious effects on wild flora and fauna as well as on human health.

Contaminants. Contaminants associated with domestic uses, livestock waste, agricultural drainage waters, chemical spills and industrial effluents, cause chronic to catastrophic impacts to fish and wildlife and their habitats.

Overharvest / Overexploitation. Some species of plants and animals have been harvested or exploited at unsustainable levels. Many of the early hunting and fishing laws and regulations were enacted to ensure that sport or commercial harvest did not overexploit these resources. Some species such as the grizzly bear and gray wolf have been deliberately extirpated from the ecoregion. In other cases, local populations of species such as elk and bighorn sheep have been extirpated through combinations of habitat degradation and overharvest of remaining animals. For example, anadromous fish populations have dwindled over the past several decades due to several reasons. Excessive depletion of remaining fish stocks by the combination of commercial, sport, and Native American harvest has exacerbated the situation. As human demands for new resources change, plant and animal species are often suddenly exploited at high rates with little or no regulatory mechanism to ensure that such exploitation is sustainable. For example, Pacific yew was reduced to low numbers of mature trees a few years ago when sudden demands for a chemical from its bark encouraged unsustainable harvesting before protective measures could be enacted.

Urbanization. The increase in human populations has led to the conversion of wildlife habitat to agriculture and home sites. As with agriculture, the impacts on wild species are multifaceted. Three major effects are: (1) loss of habitat; (2) new environmental impacts associated with human activity, and (3) increased fragmentation of existing wildlands. There is an increased demand for water removal for human use. Waste water and storm water can lead to increased water quality problems. There is an increased demand for all natural resources, creating competition. Urbanization is most pronounced in the southern portion of the ecoregion in Sonoma County--but it is a factor around all the major cities and towns in the ecoregion.

Road Building. Building of roads has had many unexpected and frequently unintended effects. Roads fragment habitat, allow easy human entry into formerly semi-protected areas, prevent use of habitat by certain species, facilitate invasion of exotic plants and animals.

Introduction of Exotic Species. Many exotic species have arrived in the ecoregion as unintended side-effects of other human activities such as agriculture and road building. However, many species such as Eucalyptus and brook trout were deliberately introduced into the environment--often with dramatic and unintended consequences to the ecosystem and to other species.

Alteration of Disturbance Regimes. Humans have drastically altered pre-European settlement disturbance regimes, particularly fire and flooding regimes. This alteration can have many negative and often long term effects on ecosystem structure and function. Many areas were regularly burned by Native Americans. Following European settlement much energy has gone into preventing both human-caused and natural fires from burning. This has generally resulted in a decrease in low intensity fires. Similarly, through dams and diversions, humans have dampened the effects of flooding along most of the rivers of the ecosystem.

Ecological Effects of Human Activities

We describe here some of the ecological effects of the human activities described above, with emphasis upon ecosystem and community level effects.

Soil Loss. Human activities, particularly logging and associated forest practices in the Coast Ranges and Klamath Mountains have resulted in accelerated soil loss from the ecoregion. This has been documented for several sites, particularly the Mad and Eel Rivers. Over 30 years two geologists from the University of California compared geologic and current erosion rates for this region and reported to the State Legislature as follows:

We have found no evidence from the last 30 years to contradict their conclusions. In fact, the accumulating evidence suggests that most all of the coastal basins within the North Coast Geologic Province south of the Smith River are eroding at rates that far surpass the rate of soil formation.

Hydrologic Disruption. Soil erosion has been accompanied by significant disruption of the hydrologic cycle. This has come about in several ways. The effects of human activities on hydrologic function are complex and do not lend themselves to simple generalizations or "cookbook" analysis procedures. Thus it is difficult to generalize about what is happening over a broad ecoregion. The following description thus represents an overview of how humans have affected hydrologic function across the ecoregion; some particular effects will apply to a given hydrobasin while others may not.

Hydrologic function is disrupted when critical phenomena is affected by human activities as outlined in Table I-14. Major functions affected include decrease in fog precipitation, timing of snow runoff, amount of infiltration (as opposed to runoff), general alteration of hydrograph (timing of river flows), and change in magnitude and frequency of flood flows.

The widespread cutting of forests appears to have decreased the amount of fog precipitation along the coast through both decreasing the fog frequency and decreasing the capacity of the vegetation to capture "fog drip". While this has not been conclusively demonstrated on a watershed or basin scale, the preponderance of evidence from stand level studies of fog precipitation suggests that removal of tree cover will reduce effective fog precipitation. There is no reason to think that the effect would not be working at larger geographic scales. This effect would only affect the north coast redwood / fogbelt portion of the ecoregion

Cutting of forests can also significantly affect the timing of runoff from snow. Snow that has accumulated in clearcut areas tends to melt earlier, thus causing increased severity of spring floods. Equally significant, overcutting of forests and overgrazing of rangelands have decreased the ability of the vegetation to intercept precipitation, thus resulting in decreased infiltration into the soil (and water table) and increased overland flow. In general, removal of vegetation can alter the hydrograph of a stream (i.e., the timing and magnitude of flows). It is hard to generalize about this phenomenon, however, because the same activity may have effects that work in opposite directions. For example, removal of the overstory canopy may decrease water infiltration into the soil but at the same time it decreases water loss to the atmosphere from transpiration.

Perhaps the most significant of all the pure hydrologic effects of humans is the alteration of the flooding regimes of rivers. This can occur indirectly from overcutting forests, overgrazing rangelands, or urbanizing wildlands. Or it can occur directly by the building and operation of dams and diversions. Floods are important events in maintaining river systems. Changing the pattern of flooding and other dynamics of the river system is detrimental to the river ecosystem. Thus "flood control" may be beneficial to some elements of human society but it can be deadly to fish, amphibians, and many other species dependent upon aquatic and riparian habitats.

There is little doubt that the major dams in the ecoregion have played a major role in altering the stream and stream side habitat of these rivers.

Water Pollution. Water pollution is typically a result of a number of effects operating simultaneously--influx of sediments and/or contaminants, decreased seasonal water flow, increased temperature of water as a result of loss of stream side vegetation or release of warmed water. Under provisions of the Clean Water Act waters which are so polluted as to prevent beneficial uses of the waters need to be declared "impaired" by the state water quality control board. It is indicative of the degree of pollution of the streams of the north coast that virtually all the major rivers south of the Smith have been declared impaired (Table I-16). In most of the North Coast streams cases the pollutant is sediment, although the streams at the southern end of the ecoregion such as Stemple Creek are impaired by nutrients, presumably from non-point source agricultural discharge. Those streams impaired by sediment tend to be those of the Coast Range Geologic province where there has been severe logging on unstable sedimentary-derived Franciscan soils. Some of the larger rivers including the Klamath, Eel and Mattole are also impaired by high temperatures, and the streams of the upper Klamath Basin (Oregon portion of the watershed) are impaired by a variety of pollutants--mostly as a result of the intensive agricultural operations in that region.

Table I-16. List of Impaired Waterbodies of the Klamath Ecoregion.

Habitat Loss. Direct loss of habitat from urbanization, suburbanization, and agricultural development is an easily observable effect in the ecoregion, although, to our knowledge it has not been quantified. It is most pronounced in the southern end of the ecoregion where the population is doubling roughly every 10 years. Most of the good agricultural lands within the ecoregion have already been developed. Thus, conversion of wildlands to agricultural land is not a major impact within most of the ecoregion. However, there are two major exceptions. In Sonoma and Mendocino Counties large acreages of wildlands are being cleared and converted to vineyards. And in various portions of the forested lands, wild forests are being converted into tree farms.

Habitat Degradation. Less dramatic but more pervasive is the degradation of habitat as a result of such things as loss of habitat structure. For example, the removal of standing dead trees ("snags") from a forest stand will make it unsuitable for bird species that nest in cavities in such snags. Habitat degradation can come about in an almost endless variety of ways and is a result of many human activities such as timber harvest, livestock grazing, water diversion, off-road vehicle use and so on. In fact, most human activities will contribute to habitat degradation for some wild species to some degree. The challenge to conservation is not to eliminate all degradation but rather to control it or zone it in both space and time so that the overall health of the larger regional ecosystem remains intact.

Habitat Fragmentation. Habitat fragmentation is the process by which habitats are increasingly subdivided into smaller units or patches resulting in loss of continuity or connectedness with other patches. It is usually accompanied by habitat loss, although certain human constructs such as highways and canals can fragment habitat with only minimal overall loss of habitat area. Furthermore, fragmentation typically results in an increase in "edge" habitat--that habitat that is found in the ecotone or area of gradation from one type to another, such as the edge of a forest. Fragmentation typically results in larger contiguous populations of species being divided up into several smaller populations with little or no interchange between them. And this, in turn, can lead to local extirpation of these populations for a variety of reasons including:

(4) combinations of these and other factors.

Within the Klamath Ecoregion the habitat fragmentation is occurring as a result of the following activities.

These are but a few of the types of fragmentation that can and is occurring in the ecoregion. Fragmentation can have an effect at many different scales. Large predatory species such as mountain lions are often the first to be affected by fragmentation since they require large blocks of contiguous habitat for survival. However, smaller species may be affected locally by such things as irrigation ditches or two-lane paved roads.

Successional Disruption / Altered Disturbance Regimes. Successional disruption occurs when the patterns of disturbance and subsequent succession are altered resulting in a changed proportion of seral or successional stages in the landscape. The cases of coast redwoods and valley oaks represent two different extremes of this sort of phenomena. With coast redwoods, late seral or old-growth once likely comprised at least 90 to 95 percent of the forest; with the accelerated cutting of the redwood forest, now less than 4 percent of the landscape consists of late seral stages. There are lots of very small redwood trees but very few big, old ones. With valley oaks, human activities such as grazing and other agricultural practices have prevented the regeneration of young oaks with the result that there are quite a number of remnant, big, old oaks but very few small or medium size trees coming along to replace them.

In both cases the natural distribution or mix of seral stages of the community has been truncated or replaced by some sort of lopsided distribution. Since many species are associated only with certain seral stages, this is accompanied by extensive loss of species--particularly those that are obligates on a particular seral stage that has been lost or drastically reduced.

Air Pollution. The effects of air pollution on ecosystem function and health are arguably less well understood than many other ecosystem level effects. Pollutants in air are known to affect species and communities in a variety of ways. For example, many amphibian species are especially sensitive to pollutants including acid rain. The same is true for many lichen species. We are not aware of any ecosystem level effects of air pollution that have been documented for the Klamath Ecoregion.

Displacement by Exotics. Exotic species displace native species in a variety of ways. In particular an exotic can cause decline or extirpation of native species by:

Numerous examples of all three types of displacement have been observed or documented within the Klamath Ecoregion.

Examples of community or ecosystem level effects are less well understood or documented, but many have been described. Exotic species can alter disturbance regimes. For example, cheatgrass can change the disturbance (fire frequency) regime for a plant community. In other cases, herbivorous species such as wild pigs may alter the plant species composition of a community.

Overexploitation / Persecution. Direct loss of species and communities from overexploitation or persecution remains a problem in the Klamath Ecoregion in spite of the fact that most natural resource professions such as forestry, range management, and particularly wildlife management have developed theory and practice to alleviate such practices. Examples from the past of species removed from the ecoregion from persecution include the gray wolf and the grizzly bear. Others, which may have been reduced in numbers from overexploitation (together with habitat degradation) include the pine marten and the fisher.

Species Loss or Endangerment

The ultimate effect of many human activities, whether they affect ecosystem structure, function or health or affect species directly, is loss or endangerment of species. The status of species loss in the Klamath Ecoregion is summarized below, and described in more detail in Volume II - Description of the Ecological Issues.

Plants. At least 62 individual vascular plant species are "at risk" within the Klamath Basin, including one that is federally endangered.

Invertebrates. One species of invertebrate (the Trinity Bristle Snail) is listed as endangered under state law. Knowledge of most invertebrates and their status is minimal.

Fish. Forty-nine stocks of anadromous salmonids (15 of chinook salmon, 20 of coho salmon, 10 of steelhead, and 4 of coastal cutthroat) have been identified as at some degree of risk. Furthermore, four non-salmonid native anadromous fish (Pacific lamprey, green sturgeon, white sturgeon, eulachon) are declining, presumably for same reasons as for anadromous salmonids. Thus, most of the native anadromous fish of the region are in decline.

The situation for resident fish is not much better. For example, seven out of twenty (35%) of the native resident fish species of the Klamath Basin are endangered or at risk. This includes the

short-nosed sucker and Lost River sucker found in the upper Klamath Basin, which are listed as federally endangered.

Amphibians and Reptiles. Ten out of fifty-two (20%) of the amphibians and reptiles of the Klamath basin are at risk, and this ratio is approximately the same for the entire ecoregion. Within the ecoregion, the California red-legged frog has been listed as federally threatened.

Birds. Many groups of birds have declined within the ecoregion:

Mammals. As with other groups a surprisingly high number of mammalian species are to some degree at risk of extinction. These include:

The relationship between human activities, ecological effects, and species loss or endangerment is not always well understood. However, the dramatic increase in endangerment and loss of species is real and serious and is in large part a result of human activities carried out for other purposes with no direct intention of causing species loss. With more humans and resultant increase in human activity the trend is likely to continue unless we make a more concerted effort to minimize the impact of these activities. As will be discussed in Volume III - A Holistic Strategy for Restoration of the Ecoregion, putting all the effort on saving species once they are already at risk is unlikely to be efficient or effective in the long run. Rather it is important that we also look at and change the root causes of such endangerment--the human effects on the ecosystem.