CHAPTER 1. INTRODUCTION

Scientists and the concerned public agreed that a coordinated, cooperative, conservation initiative focusing on landbirds was needed to address the problem. In late 1990, Partners in Flight (PIF) was conceived as a voluntary, international coalition of government agencies, conservation groups, academic institutions, private organizations, and citizens dedicated to "keeping common birds common" and "reversing the downward trends of declining species".

PIF functions to direct resources for the conservation of landbirds and their habitats through cooperative efforts in the areas of monitoring, research, management, and education, both nationally and internationally. The foundation of PIF's long-term strategy for bird conservation is a series of geographically based Landbird Conservation Plans, of which this document is one.

A. Goal

The primary goal of PIF Landbird Conservation Planning is to ensure long-term maintenance of healthy populations of native landbirds. This document is intended to facilitate that goal by stimulating an active approach to landbird conservation. An overview of the process and recommended actions is presented in Figure 1. The strategy primarily addresses nongame landbirds, which have been vastly under-represented in conservation efforts, and many of which are exhibiting significant declines that may be reversed if appropriate management actions are taken. PIF Landbird Conservation Planning provides the framework to develop and implement conservation strategies by recommending actions on the ground that may prevent the need for future listings.

B. Process

PIF Landbird Conservation Planning emphasizes effective and efficient management through a four-step process designed to describe and achieve actions necessary for landbird conservation. These include:

identify habitats and species that are conservation priorities,

describe desired conditions for priority habitats and species,

develop biological objectives that can be used as management targets to achieve desired conditions, and

recommend conservation strategies that can be implemented at multiple scales to achieve biological objectives.

Figure 1.

C. Integration

This conservation plan is one of five plans that will be coalesced into a bi-state plan that will cover all the priority habitats and landbirds in Oregon and Washington. The plan has benefitted from extensive discussions and integration with other state PIF plans, especially Idaho (S. Ritter pers. comm.). PIF Landbird Conservation Plans also are intended to complement other conservation initiatives such as the North American Waterfowl Management Plan, the National Shorebird Conservation Plan, and North American Colonial Waterbird Plan. Ongoing efforts to integrate with these initiatives during objective setting and implementation will help ensure that healthy populations of all native bird species continue to exist, and that all of our native ecosystems have complete and functional avifaunal communities.

PIF Bird Conservation Plans are one of many recent efforts that address conservation of natural resources and ecosystems in the Pacific Northwest. This plan is intended to supplement and support other planning and conservation processes (e.g., Habitat Conservation Plans, Washington State Landowner Landscape Plans, The Nature Conservancy Ecoregion Plans) and regulatory enactments (e.g., State Forest Practices Act, Endangered Species Act) by describing a conservation strategy for landbirds that are often not addressed or only incidentally addressed in other plans. In particular, we envision extensive integration with the most comprehensive land management plan for the region, the Interior Columbia Basin Ecosystem Management Plan (ICBEMP). It is anticipated that biological objectives and conservation strategies described in this document and future versions will be integrated not only with ICBEMP, but also with other ongoing and future conservation planning in the Columbia Plateau to provide functioning ecosystems for the region's diverse array of landbird species.

CHAPTER 2. THE PLANNING UNIT

The Columbia Plateau Landbird Conservation Planning Unit (Figure 2) includes mostly low elevation, non-conifer forest cover types in eastern Oregon and Washington. Habitat types emphasized in this document are shrub-steppe and riparian, but conservation issues and strategies are also described for juniper, mountain mahogany, aspen, and cliff and rimrock habitats. The planning unit encompasses several ecoregions including the Owyhee Uplands, Basin and Range (Great Basin), and High Lava Plains in Oregon, the Palouse Prairie in Washington, and the Columbia Basin in Washington and Oregon (Franklin and Dyrness 1973). Geographic boundaries are not rigorously defined but dependent on the presence of our priority habitats (see Chapter 5). For the purposes of consistency with the ICBEMP, we use the boundaries of their Northern Great Basin and Owyhee Uplands Ecological Reporting Units (ERUs) (Wisdom et al. in press) for our subprovinces of the same name. However, we separate their Columbia Plateau ERU into 3 subprovinces - Columbia Basin in Oregon and Washington, High Lava Plains in Oregon, and Palouse Prairie in Washington. We also extend a narrow portion of the Columbia Basin subprovince up the Okanogan Valley to the Canadian border into what is part of the ICBEMP Northern Glaciated Mountains ERU (Figure 2).

This conservation strategy does not include conifer forests and associated habitats in the Cascade, Blue, Ochoco, Okanogan, Selkirk, and Klamath Mountain Ranges. These areas are covered in two other PIF bird conservation plans; Conservation strategy for landbirds in the Central Rocky Mountains of eastern Oregon and Washington and Conservation strategy for landbirds in the East-slope Cascades of eastern Oregon and Washington. These can be viewed and downloaded from the Oregon Washington PIF web page at www.gorge.net/natres/pif.html.

B. Physical Features

The Columbia Plateau is a vast landscape of arid and semi-arid habitats that begins in the rainshadow of the Cascade Mountains and extends east to cover most of the non-forested portions of eastern Oregon and Washington. The region is characterized by a relatively uniform underlying geology dominated by thick flows of basalt lava that are punctuated in localized areas by volcanic ashflows and deposits of volcanic tuffs and rhyolite. The uniform bedrock of the Columbia Plateau has been faulted and uplifted, cut by rivers and eroded by wind, water, and glaciers to produce a diverse landscape that contains considerable topographic relief. Present within the landscape are desert mountain ranges, low rolling hills, riverine valleys, broad basins containing permanent lakes and seasonal playas, sand dunes, plateaus, and expansive plains. Many of the current features present in the region date only from the Pleistocene epoch or one million years before present. This is a relatively new landscape that is continuing to change and be altered by natural processes.

In this arid landscape, riparian and wetland habitats have special importance and provide significant distinction to the region. The planning unit contains two very different types of river systems, one

Figure 2

which has direct connections to the Pacific Ocean and in many instances still supports anadromous fish populations, and the other which contains only internally drained streams and is one of the defining characteristics of the hydrographic Great Basin. Throughout the region, rivers flow through varied terrains including glacially-carved gorges, river-carved canyons, and broad valleys which adds considerable diversity to the riparian habitats present. As elsewhere, river basins act to divide the landscape into large geographic divisions, which also act to segment wildlife populations and species distributions.

C. Vegetation

A thorough description of the historic and current vegetation in the planning area is beyond the scope of this document. The information presented below is a cursory overview of the principal features of the vegetation and plant associations that provide habitat for landbirds. More detailed accounts have been described in several sources including Daubenmire (1970), Franklin and Dyrness (1973), Dobler et al. (1996), Quigley and Arbelbide (1997), and Paige and Ritter (1999).

1. Pre-European Settlement

The landscape at the time of European settlement was dominated by shrub-steppe vegetation communities (Daubenmire 1970), dissected by riparian corridors, pockets of wetlands, and grasslands, in particular the Palouse Prairie. The most prominent habitat in the shrub-steppe was sagebrush shrublands. Intermixed in the sagebrush habitat were western juniper woodlands (typically confined to ridges and rocky soil habitats) and montane shrublands which transitioned to extensive aspen forests found on the highest mountain ranges in the region. In the Great Basin ecoregion, internally drained basins containing alkaline soils were dominated by salt desert scrub vegetation. These habitats were relatively barren when compared to the more lush sagebrush/bunchgrass habitats. Specialized habitats defined by unique soils, hydrology or the combination of soils and vegetation occurred in localized areas throughout the planning unit. The dominant ecological process that affected vegetation across the region was wildfire ignited by lightning as well as some Native American ignitions. Irregular and spotty wildfires created a landscape that was a patchwork of stand ages in shrub-steppe that was interspersed with grasslands and other small, unique communities (Paige and Ritter 1999).

Shrub-steppe communities were mostly codominated by shrubs and perennial bunchgrasses with a microbiotic crust of lichens and mosses on the surface of the soil. Dominant shrubs were sagebrush of several species and subspecies--Basin, Wyoming, and Mountain big sagebrush; low sagebrush; and early, rigid, threetip and black sagebrush (Table 1). Bitterbrush also was important in many shrub-steppe communities. Bunchgrasses were largely dominated by four species--bluebunch wheatgrass, Idaho fescue, needle and thread grass, and Sandberg's bluegrass. Soils, climate and topography acted to separate out distinct plant communities that paired sagebrush species with specific bunchgrasses across the landscape.

Riparian vegetation is quite restricted in the arid intermountain west, but is nonetheless fairly diverse. It is characterized by a mosaic of plant communities occurring at irregular intervals along streams and dominated singularly or in some combination by grass-forbs, shrub thickets, and mature forests with tall deciduous trees. Common shrubs in riparian zones included several species of willows, red-osier dogwood, hackberry, mountain alder, Wood's rose, snowberry, and currant (Table 1). Herbaceous understories were very diverse, but typically included several species of sedges along with many dicot species. In presettlement times, riparian habitats were found at all elevations and on all stream gradients; they were the lifeblood for most wildlife species with upwards to 80% of all wildlife species dependent upon these areas at some time in their lifecycle (Thomas et al. 1979). Many riparian habitats were maintained by beaver activity which was prominent throughout the west. Beaver-dammed streams created pools that harbored fish and other species; their dams also reduced flooding and diversified and broadened the riparian habitat. The other important ecological process which affected riparian areas was natural flooding that redistributed sediments and established new sites for riparian vegetation to become established.

Table 1. Native vegetation characteristic of the Columbia Plateau Landbird Conservation Planning Region.

Western juniper woodlands were relatively restricted in their distribution in the Columbia Plateau. They occurred mainly on ridges where fire was infrequent but their associated understories of sagebrush and bunchgrasses were almost as diverse as the shrub-dominated communities so common across the landscape. Within the shrub-steppe landscape there also were alkaline basins, many of which contained large lakes during wetter pluvial times, where extensive salt desert scrub communities occur. This characteristic Great Basin vegetation contained numerous shrubs in the shadscale group including greasewood which has a very wide ecological amplitude, being equally at home in seasonally flooded playas and on dunes or dry hillsides. Salt desert scrub communities were surprisingly diverse from a floristic standpoint and provided habitat for many wildlife species.

2. Current Vegetation

Vegetative natural communities in the Columbia Plateau have undergone changes with the advent of European settlement in the last 150 years. Native shrub-steppe communities have been diminished both in extent and condition. The principle factors were livestock overgrazing, invasion and dominance of non-native plants, and extensive conversion to agriculture (Wisdom et al. in press). Other contributing factors included development, sagebrush eradication programs, and changes in fire regimes (Paige and Ritter 1999). In eastern Washington, nearly 60% of the native shrub-steppe has been converted to agriculture (Dobler et al. 1996). Even in extant shrub-steppe, what appears to be a natural landscape dominated by an "ocean of sagebrush" is actually a considerably altered ecosystem that compositionally and functionally differs from prior conditions. These changes have had effects on wildlife species with many bird species continuing to decline long after the worst of the impacts to habitats have ceased.

Grassland ecosystems that were prominent in the Columbia Basin portion of the planning unit have suffered the greatest losses of any habitats in the Columbia Plateau (Oregon GAP 1999). The Palouse Prairie has been identified as the most endangered ecosystem in the United States (Noss et al. 199?). Land conversion and livestock grazing coupled with the rapid spread of cheatgrass and a resulting change in the natural fire regime has effectively altered much of the grassland habitats. The second-most set of impacted ecosystems in the region are the valley bottomlands that originally were a mix of riparian vegetation, Basin wildrye meadows, and rich sagebrush steppe. Land conversion, grazing and hydrologic alteration has effectively removed much of the native vegetation from these bottomlands, and so altered the streams that most are no longer in proper functional condition.

While these losses are significant, perhaps of even more concern are changes that have occurred throughout the mostly sagebrush dominated ecosystem of the shrub-steppe. Grazing, exotic species and altered fire regimes have impacted this ecosystem to the effect that it is difficult to find stands which are still in relatively natural condition. The greatest changes are the reduction of bunchgrass cover in the understory and an increase in sagebrush cover. Soil compaction is also a significant factor in heavily grazed lands affecting water percolation, runoff and soil nutrient content. Western juniper woodlands have greatly expanded their range, now occupying much more of the sagebrush ecosystem than in pre-European settlement times. The reasons for the expansion are complex and include interactions between climate change and changing land use, but fire suppression and grazing have played a prominent role in this dramatic shift in structure and dominant vegetation. Losses have been less dramatic and extensive in salt desert scrub ecosystems and in montane shrublands and aspen forests where grazing, mining and altered hydrology have been the primary threats.

Riparian areas have been extensively impacted within the Columbia Plateau such that undisturbed riparian systems are rare (Knutson and Naef 1997). Impacts have been greatest at low elevations and in valleys where agricultural conversion, altered stream channel morphology, and water withdrawal have played significant roles in changing the character of streams and associated riparian areas. Losses in lower elevations include large areas once dominated by cottonwoods that contributed considerable structure to riparian habitats. In higher elevations, stream degradation occurred with the trapping of beaver in the early 1800's, which began the gradual unraveling of stream function that was greatly accelerated with the introduction of livestock grazing. Woody vegetation has been extensively suppressed by grazing in some areas, many of which continue to be grazed. Herbaceous vegetation has also been highly altered with the introduction of Kentucky bluegrass that has spread to many riparian areas, forming a sod at the exclusion of other herbaceous species. The implications of riparian area degradation and alteration are wide ranging for bird populations which utilize these habitats for nesting, foraging and resting. Secondary effects which have impacted insect fauna have reduced or altered potential foods for birds as well.

D. Land Uses

Post-European settlement land uses were primarily open-range grazing by livestock and agriculture, which began with land clearing in the late 1800s. Both continue to be the dominant land uses, particularly since damming of the Columbia River in the 1930s provided irrigation water to areas previously unsuitable for agriculture. Grazing continues to varying degrees, particularly on large tracts of federal lands (Quigley and Arbelbide 1997) in the Northern Great Basin, High Lava Plains and Owyhee Uplands subprovinces.

Within the ERUs of the ICBEMP, the greatest conversion to agriculture has been the Columbia Plateau (our Columbia Basin and High Lava Plains), where nearly half of the land base has been converted to agriculture (Wisdom et al. in press). Agriculture now occupies over 10% of the Owyhee Uplands ERU, but the Northern Great Basin ERU remains relatively free of agriculture conversions.

What is deceiving about this relatively low percentage of land conversion in the Owyhees and Great Basin is that the conversions have been concentrated in low elevation valleys and have significantly impacted valley bottom grasslands, shrublands, and cottonwood dominated riparian areas.

Agricultural land uses include dry land wheat farms and hybrid poplar wood fiber farms in the Columbia Basin, intensive irrigated agricultural row crop production in the Columbia Basin and the High Lava Plains, and irrigated agriculture associated with livestock production (alfalfa and hay) in all subprovinces. Grazing occurs across the planning unit but is more prominent in the Northern Great Basin and the Owyhee Uplands where it is the dominant land use on private and public lands.

In addition to grazing and agriculture, there has been patchy, permanent losses of shrub-steppe habitat due to urban and rural residential growth. These losses are most obvious in central Oregon near the Bend-Redmond area, and in southeastern Washington in the Tri-cities area.

E. Conservation Issues

Landbird conservation faces numerous obstacles, either directly or indirectly arising from conflicts with human economic issues. The principal post-settlement conservation issues affecting bird populations include habitat loss and fragmentation resulting from conversion to agriculture; and habitat degradation and alteration from livestock grazing, invasion of exotic vegetation, and alteration of historic fire regimes. Conversion of shrub-steppe lands to agriculture adversely affects landbirds in two ways: 1) native habitat is in most instances permanently lost, and 2) remaining shrub-steppe is isolated and embedded in a highly fragmented landscape of multiple land uses, particularly agriculture. Fragmentation resulting from agricultural development or large fires fueled by cheatgrass can have several negative effects on landbirds. These include: insufficient patch size for area-dependent species, and increases in edges and adjacent hostile landscapes, which can result in reduced productivity through increased nest predation, nest parasitism, and reduced pairing success of males. Additionally, fragmentation of shrub-steppe has likely altered the dynamics of dispersal and immigration necessary for maintenance of some populations at a regional scale. In a recent analysis of neotropical migratory birds within the Interior Columbia Basin, most species identified as being of "high management concern" were shrub-steppe species (Saab and Rich 1997).

Approximately 6 million hectares of shrub-steppe have been converted to wheat fields, row crops, and orchards in the interior Columbia Basin (Quigley and Arbelbide 1997). In Washington over 50% of historic shrub-steppe has been converted to agriculture (Dobler et al. 1996).

The legacy of livestock grazing in the Columbia Plateau has had widespread and severe impacts on vegetation structure and composition. One of the most severe impacts in shrub-steppe has been the increased spread of exotic plants. Riparian habitats are known to be detrimentally affected by most grazing practices tested to date (Saab et al. 1995).

Other conservation issues affecting landbird populations and their habitats in the Columbia Plateau include:

water management - stream channelization, dams, diversions, and irrigation;

changes in hydrology resulting in increased salinity (plants not adapted to high levels of salinity);

urban development;

exotic plant seedings such as conversion of native shrub-steppe habitats to crested wheatgrass seedings (Reynolds and Trost (1980);

cats (feral and domestic); and

resource competition from aggressive non-native competitors (e.g., starlings for cavities).

F. Conservation Opportunities

Despite extensive habitat losses and conversions from original plant communities, opportunities exist for restoration and enhancement of habitats to provide quality landbird habitat. Several large tracts of shrub-steppe in eastern Washington and much of eastern Oregon are under state or federal ownership where the public can participate in the process of land management decisions. Federal agencies such as the Bureau of Land Management also are active in land exchanges to acquire important areas for conservation. In addition, programs are in place on federal lands (e.g., Oregon plan for salmon and watersheds, Government Applications Task Force Northwestern Riparian Zone Assessment and Restoration Project, Washington Salmon Recovery Project) to restore altered riparian and associated upland habitats with native species and natural ecological processes.

Restoration of shrub-steppe is still very much a fledgling field, and complete restoration of degraded or converted shrub-steppe may not be feasible. Conservation efforts must therefore concentrate on existing shrub-steppe that can be permanently protected and managed through easement, acquisition, or land trusts. Agricultural conversion has been concentrated in shrub-steppe areas of arable, deep soil communities, which support greater abundance of some shrub-steppe passerines than other soil types (Vander Haegen et al. in press). Because of this, it would be appropriate to focus conservation efforts in deep soil communities. Conservation also may be appropriate on some agricultural lands (e.g., grasshopper sparrows on CRP). Several government outreach and incentive programs, many of which resulted from the 1996 Farm Bill, provide opportunities to accomplish this (see Chapter 9). In riparian habitat, the complete removal of livestock has been shown to have measurable positive affects on riparian obligate bird species within several years (Krueper 1993).

G. Subprovinces

The Columbia Plateau Landbird Conservation Planning Region is a large area (Figure 2). Many similarities in habitats, management practices, and land uses are common to the entire area. However, environmental and anthropogenic differences exist within several relatively distinct geographic areas. This provides an opportunity to establish biological objectives at smaller geographic scales where appropriate. Throughout this document, we refer to the following five Subprovinces:

Columbia Basin

High Lava Plains

Basin and Range (Great Basin)

Owyhee Uplands

Palouse Prairie

CHAPTER 3. AVIFAUNA

This conservation strategy addresses the conservation of breeding landbirds and their habitats in the Columbia Plateau of eastern Oregon and Washington. Clearly, factors operating outside the nesting season may be adversely affecting populations of birds breeding in the Columbia Plateau. This may be particularly true for migratory birds subject to habitat changes and other factors on their wintering grounds and during migration, but also for resident birds where adverse factors affecting breeding populations may be doubly affecting species wintering in the same habitats. There is an underlying assumption throughout this document that maintaining quality habitat for breeding landbirds also is important in supporting populations of wintering and migrant birds of the same and other species.

The conservation strategy does not directly address all landbird species, but instead uses numerous "focal species" to describe the conservation objectives for the avian community. The strategy also does not address birds that primarily use aquatic habitats such as shorebirds and wading birds (e.g., spotted sandpiper, great blue-heron), waterfowl (e.g., mallard), and colonial waterbirds (e.g., yellow-headed blackbird). Conservation planning for these types of birds is being conducted by other entities and programs (i.e., North American Waterfowl Management Plan, National and Regional Shorebird Plans, and North American Colonial Waterbird Plan, respectively).

B. Species Composition

We considered approximately 129 native landbird species to be highly associated breeding species in all or parts of the Columbia Plateau (Appendix A). This does not include a number of landbird species that may occur in the planning unit (particularly in riparian habitats), even occasionally as breeding species, but which are not considered to be highly associated or regular components of the avifauna in the Columbia Plateau. Additionally, many other species may occur as migrants or wintering species only. This diversity reflects the variety of habitats and environmental influences within the planning area.

1. Shrub-Steppe

We considered approximately 56 native landbird species to be highly associated breeding species in shrub-steppe habitats (Appendix A). Although shrub-steppe habitat supports relatively few species of landbirds (Rotenberry and Wiens 1978, Wiens et al. 1986), several species are dependent upon this vegetation type such that they are found nowhere else in Oregon and Washington. These include the shrub-steppe obligates: sage grouse, sage sparrow, sage thrasher, and Brewer's sparrow, and other non-obligate species such as burrowing owl, Swainson's hawk, ferruginous hawk, loggerhead shrike, long-billed curlew, sharp-tailed grouse, upland sandpiper, and black-throated sparrow.

2. Riparian

We considered approximately 97 native landbird species to be highly associated breeding species in riparian habitats (Appendix A). In contrast to shrub-steppe, riparian habitat typically supports the greatest diversity of landbird species. As with shrub-steppe, there are several species dependent on this habitat type in the Columbia Plateau (e.g., western wood-pewee, Bullock's oriole, willow flycatcher, yellow-breasted chat, yellow-billed cuckoo, yellow warbler). However, most of these species also occur in riparian habitat elsewhere in Oregon and Washington.

C. Species and Habitat Associations

An essential component for deciding appropriate management actions to conserve landbirds is an understanding of relationships between species and habitat. These data are presented with each species account in Chapter 6. A more complex synthesis of knowledge on species and habitat relationships is being compiled as part of a bi-state project entitled Wildlife Habitats and Species Associations in Oregon and Washington (Johnson and O'Neil in prep.). Products resulting from this project should be considered an appendium to this document, and function as an information source used to make appropriate decisions on species management within specific habitat conditions.

D. Population Trends

The Breeding Bird Survey (BBS) (Robbins et al. 1986) is the primary source of population trend information for North American landbirds. However, it only has data for the last 30 years, and extensive habitat changes occurred prior to that time which undoubtably affected bird populations, but for which there are no quantitative data. Attempts to assess the extent of bird population changes prior to the BBS have been documented through an examination of historical habitats at the time of European settlement (approximately 1850) and knowledge of bird species-habitat relationships (Wisdom et al. in press). This information is presented in Chapter 6 under each species account.

There is one BBS Physiographic Region within the geographic boundaries of this conservation strategy - Columbia Plateau. This BBS physiographic region also includes areas outside of Oregon and Washington - southern Idaho, and extreme northwestern Nevada. BBS trend estimates for species primarily associated with shrub-steppe and riparian habitats in the Columbia Plateau are presented in Appendix A for the 30-year period (1968-1998) and the most recent period (1980-1998).

Of the 16 species with significantly declining trends in the Columbia Plateau, six could be considered exclusively or primarily associated with shrub-steppe, four with open or agricultural lands, five with riparian/wetland habitat, and one with forest habitat (Table 2). Additionally, some species that lack sufficient BBS data are considered by many to be declining in the Columbia Plateau (e.g., sage grouse, sharp-tailed grouse, Lewis' woodpecker) based on anecdotal knowledge of bird species-habitat relationships, and the extent of those habitats historically across the planning area (Wisdom et al. in press). This includes some local and regional extirpations of breeding populations such as sage grouse in much of eastern Washington, and sharp-tailed grouse throughout Oregon. One species, yellow-billed cuckoo, may have been completely extirpated as a breeding species from the region.

In contrast to declining species, 20 species have significantly increasing trends (Table 2). Only four of these species would be considered primarily associated with shrub-steppe, and four with riparian habitat. Most of the remainder are open country/agriculture or generalist species and five are forest species.

Table 2. Native landbird species with significantly declining or increasing population trends in the Columbia Plateau BBS Physiographic Region (from Sauer et al. 1999).

^a L= long-term trend (1966-1998); R= recent trend (1980-1998).

In addition to identifying declining species, we used BBS data for some species as a baseline to set population trend objectives for reversing or stabilizing declining trends over some period of time. A list of BBS routes and their location is presented in Table 3.

Table 3. Breeding Bird Survey routes in the Columbia Plateau Landbird Conservation Planning Region.^a

^a Includes route if it is mostly within these regions; some routes also extend into other physiographic regions.

CHAPTER 4. CONCEPTUAL APPROACH

Given the limitations of these approaches, we developed a "hybrid" strategy for landbird conservation in the Columbia Plateau that emphasizes ecosystem management, but includes components of single-species and guild or indicator species management. This approach is based on the following assumption:

A conservation strategy that emphasizes ecosystems is more desirable than one that emphasizes individual species.

In the typical PIF approach to bird conservation, species most in need of conservation action are designated as priority primarily by a quantitative scoring system. The National PIF Priority Scores Website (Partners in Flight Bird Prioritization Technical Committee 1999) is the source used for prioritizing birds based on a scoring system of seven variables (Carter et al. in press). If using this process exclusively, the emphasis is on single-species conservation, but there is an underlying assumption that conservation of priority species supports ecosystem management because other species will likely benefit from actions implemented to conserve priority species. This assumption may be appropriate when priority species are associated with declining habitat (e.g., old-growth forest, grasslands), degraded habitat (e.g., western riparian systems), or habitat features that are reduced across the landscape (e.g., snags).

We supplemented the typical PIF approach by placing a greater emphasis on ecosystems. We recognized that there were a number of habitat features or conditions important for birds in a functioning ecosystem that did not have a priority species associated with them. In addition, we recognized the potential importance of community dynamics operating at various spatial scales that may involve species that are not considered priority. Thus, desired conditions for these habitat features or functional relationships would not be described by the priority species approach. In order to have a more complete ecosystem approach, and provide a better planning framework for dealing with future species of concern, we first identified the most important habitat conditions and features used by landbirds within the scope of this plan. After the initial PIF priority species were determined and their habitat associations and conditions matched with our list, additional species were selected based on their degree of association with the remaining important habitat conditions and features.

This approach resulted in a conservation strategy that includes both uncommon (even rare) and common species. Uncommon species are typically high-scoring PIF priority species based on populations status, declining trends, vulnerability, etc. Common species are representative of some habitat condition or feature that did not have an associated high-scoring priority PIF species, but that we felt was important for birds in a functioning ecosystem of that habitat type. In some instances, extirpated or nearly extirpated species (e.g., yellow-billed cuckoo, sage grouse) are included as priority species if we felt they could potentially be reestablished and/or were highly indicative of some desirable habitat condition.

Using this blend of approaches, we feel there is a much greater likelihood of maintaining key habitat attributes and providing functioning ecosystems for birds because the most important habitat conditions and habitat attributes for landbirds are described through this expanded group of species. We refer to these species as "focal species" (see below) because they are our focus for describing desired conditions and attributes. The rationale for using focal species is to draw immediate attention to habitat features and conditions most in need of conservation or most important in a functioning ecosystem. Although conservation is directed towards focal species, establishment of conditions favorable to focal species also will likely benefit a wider group of species with similar habitat requirements.

Most of what we know about landbird ecology in the Columbia Plateau exists at the scale of individual birds, small populations, or the site-level. Since this strategy is designed to be an ecosystem planning tool, it will be necessary to design and implement management at the landscape-level. Landscape planning will require addressing regional populations or sub-populations of birds that occur across several subprovinces. However, little is known about relationships between landbird populations and habitat at this larger scale. The strategy will introduce hypotheses, using currently known biological information as the basis, to be tested in an effort to expand our knowledge of landbird biology and management toward the landscape scale.

Finally, monitoring of habitat attributes and focal species will provide a means of tracking progress towards conservation. Monitoring will provide essential feedback for demonstrating adequacy of conservation efforts on the ground, and guide the adaptive management component that is inherent in this approach.

A. Biological Objectives

Biological objectives are the cornerstone of this conservation strategy. Stated simply, they are "what we think the birds need". They are not regulatory, nor do they represent the policies of any agency or organization. Our biological objectives are intended to stimulate conservation action, and to function as a starting point for discussion of integration with broader ecosystem-based objectives. Our development of biological objectives emphasized the following assumption:

Measurable, quantitative objectives are more desirable than descriptive, qualitative objectives.

Thus, we attempted to establish quantitative objectives whenever possible. Establishing quantitative biological objectives serves several purposes:

They stimulate conservation actions to a greater degree than descriptive, qualitative objectives by providing land managers with numerical targets within an ecological context (e.g., habitat, landscape).

They provide targets for designing management plans and benchmarks for measuring success of management actions.

They provide hypotheses for research, particularly when objectives are based on assumptions and/or professional judgement due to lack of data.

They are probably our best form of outreach to communicate to others what is needed to conserve landbirds.

Our biological objectives are primarily habitat-based, and are derived from current knowledge and professional judgement about bird-habitat relationships. Because of variability in the type, quality, and amount of data on focal species, some biological objectives are detailed and quantitative and others are descriptive and qualitative. Because data are limited for many species, biological objectives are often based on assumptions, which become the basis for research as testable hypotheses.

Three factors were paramount in setting quantitative biological objectives:

means (rather than minimums) of available data were often used because they more likely provide adequate conditions for maintaining populations,

a range of values was often used to represent the plasticity of a species relationship with a habitat condition and to acknowledge the Historical Range of Variation (HRV) that likely occurred for many habitat conditions, and

optimal or high quality habitat was emphasized (to the degree of our knowledge) for self-sustaining populations in geographic areas most suitable for maintaining or providing that habitat.

Focal species also may occur at various population levels in habitats with conditions outside the range of our objectives, and areas outside of our geographic emphasis. These populations may or may not be source habitats (i.e., provide resources for successful reproduction), and may or may not contribute to conservation of that species. However, this conservation strategy emphasizes setting biological objectives for the most desirable habitat conditions within areas where focal species habitat is or should be most suitable.

Unless otherwise indicated, data on population density or abundance are used to indicate habitat suitability. This assumes healthy, viable populations where species are most abundant, despite widely accepted recognition that population density and associated habitat quality can be a misleading or inaccurate measure of population viability (Van Horne 1983). From a practical standpoint, this habitat-based approach has been widely used because of the ease and cost effectiveness of collecting such data, and demographic information is often unavailable. A consistent theme throughout this conservation strategy is that use of habitat quality to represent population health is an assumption that will ultimately need to be validated with demographic data to determine relationships between habitat characteristics and population viability.

B. Conservation Strategies

Conservation strategies are examples of management actions that may be used to achieve biological objectives or enhance conservation relative to a habitat attribute or focal species. They are recommendations that can be incorporated into management practices or implemented on an opportunistic basis within the broader context of ecosystem management. Management techniques suggested include only a few of the wide variety of options available. Land managers and biologists should consult with plant ecologists and scientists from other disciplines to ascertain appropriate conservation options to prescribe for specific areas. These individuals also can be a valuable source of information for additional management actions to achieve biological objectives.

C. Bird Conservation Areas

We identified several Bird Conservation Areas (BCAs) to function as an additional tool for bird conservation (see Appendix B). BCAs are desirable because habitat losses and landbird species declines have been extensive, and habitats that remain are disjunct and threatened by continued development or conversion to non-suitable habitat. Some bird species may only be able to persist if actions are taken to emphasize conservation in selected areas.

BCAs are intended to provide a focus for any agencies, non-governmental organizations or companies, or private individuals to prioritize where conservation should occur. They represent what we feel are currently the best geographic options for maintaining or enhancing healthy populations of landbirds to stem the tide of declines and prevent further listings of species. However, it should not be inferred that they are the only areas suitable for bird conservation. It also will be important to initiate conservation actions where opportunities present themselves. BCAs should function to direct conservation efforts where actions have the greatest opportunity for regional success.

BCAs were selected based on the professional knowledge of biologists and ecologists that participated in this planning process. Numerous factors were considered including uniqueness of the area, existing populations of focal species, historic and current condition of the habitat, current and projected land uses and land management, threats and risk of loss/degradation of the habitat, and land ownership.

It is hoped that various partners in landbird conservation will adopt either singularly or in partnership each of the BCAs to facilitate coordination of conservation actions within each area. This should include an assessment of existing habitat conditions within the BCA, and specific management strategies on how to achieve conservation objectives. Management and evaluation of BCAs should emphasize healthy, native vegetation within the historical range of variation for each habitat type. The result should be a managed landscape mosaic within the BCA that includes potential habitat for some or all priority species.

CHAPTER 5. PRIORITY HABITATS AND SPECIES

Priority habitats were selected by the Columbia Plateau Working Group (see Acknowledgments) using a combination of factors including:

priority status in an Oregon-Washington PIF prioritization scheme (Andelman and Stock 1994),

loss, alteration, and current condition of the habitat relative to that of historic conditions (e.g., see historical source habitats in Wisdom et al. in press),

recognition of current threats of loss or conversion of the habitat, and

importance of the habitat to one or more high priority species.

Herbaceous dominated wetlands are not emphasized in this conservation strategy for several reasons. First, only a few landbirds are closely associated with these habitats (e.g., common snipe, common yellowthroat, marsh wren, red-winged blackbird). Additionally, these habitats are being addressed by other bird conservation initiatives (e.g., North American Waterfowl Management Plan, Regional Shorebird Plans) and by several regulatory enactments (e.g., Section 404 of the Clean Water Act). Thus, our emphasis was to focus on upland habitats that are not receiving much conservation emphasis or regulatory protection.

Priority species were selected using a combination of several factors including:

primary association with priority habitats for breeding;

specialist species that are obligate or highly associated with key habitat features/conditions important in functioning shrub-steppe or riparian ecosystems;

declining population trends (Table 2) or reduction in their historic breeding range (may include extirpated species);

special management concern or conservation status such as threatened, endangered, species of concern, management indicator species, etc.;

high Management Index scores in the OR-WA PIF prioritization process (Andelman and Stock 1994) or the ICBEMP conservation assessment process (Saab and Rich 1997);

high total or AI (Area Importance) + PT (Population Trend) scores in the PIF National Database for the Columbia Plateau physiographic province (Appendix A);

species for which the Columbia Plateau physiographic Region has a high national responsibility (i.e., high percent population scores) (Appendix A); and

professional knowledge on species of local interest.

Two landbird species considered high priority species in Columbia Plateau by several federal and state agencies, sage grouse and sharp-tailed grouse, also are included in this conservation strategy. Currently, several government agencies and other organizations are working specifically on conservation of these species. Although we established coarse-scale objectives for both sage and sharp-tailed grouse, we refer the reader to much more detailed conservation objectives and management strategies already developed for these species (see Chapter 6 species accounts for references). Conservation objectives for these species in this document are intended to be integrated with those other directives for conservation. This should be especially applied where BCAs have been designated. It is hoped that agencies and organizations attempting to implement landbird conservation or grouse conservation will fully avail themselves of the management strategies for both efforts.

B. Priorities

Two habitat types were selected as priority habitats: shrub-steppe and riparian. Additionally, several unique habitats such as aspen stands, mesic agricultural fields, juniper woodland, mountain mahogany, and cliffs and rimrock are considered priority habitats for conservation. Our intent was to avoid rigorous definitions for these habitats, and to allow land managers flexibility to ascertain if the conditions we describe are ecologically appropriate for management on their lands within the broad context of the habitat types. However, the following guidelines may help when considering the applicability of our objectives. We use the term shrub-steppe as encompassing both grasslands (steppe) and shrublands dominated by sagebrush or other shrub species. Our definition of riparian is the vegetative structure (primarily shrubs and trees, but also the herbaceous ground cover) influenced by the hydrology of the aquatic system. We do not emphasize herbaceous dominated wetlands for reasons described above.

1. Shrub-Steppe

We delineated five habitat types for landbirds within the broad definition of shrub-steppe (Table 5). However, much of our emphasis is on sagebrush habitats, particularly big sagebrush communities. Among shrub-steppe habitat types, big sagebrush has several obligate or near-obligate species, and probably has been adversely impacted more than the other types. Other forms of sagebrush such as low sage, are of less value to birds, and less threatened than big sagebrush (Paige and Ritter 1999).

Landbird conservation in shrub-steppe habitats emphasizes maintaining healthy ecosystems through representative focal species for several habitat conditions in five habitat types (Table 4). In Steppe and Steppe-Shrubland, the conditions include native bunchgrass cover, interspersion of tall shrubs and openings, and the presence of burrows. In Sagebrush, the overall desired condition is expansive areas of high quality sagebrush with a diverse understory of native grasses and forbs. More specific desired conditions include large unfragmented patches of sagebrush, and desirable conditions of sagebrush cover and height. In Shrublands, conditions of concern are ecotonal edge habitats between shrubs, trees, and herbaceous openings; and upland, sparsely vegetated desert scrub habitats. In Juniper-Steppe, the desired condition is the presence of scattered mature juniper trees (i.e., savanna).

Table 4. Priority habitat features and associated focal species for conservation in shrub-steppe habitats of the Columbia Plateau Landbird Conservation Planning Region.

na = not applicable

2. Riparian

Landbird conservation in riparian habitats emphasizes maintaining healthy ecosystems through representative focal species for two riparian types, Woodland and Shrub, and several conditions (features) within each type (Table 5). In Woodland, these conditions include the presence of snags, large canopy trees, subcanopy foliage, a dense shrub understory, and large, structurally diverse patches of habitat. In Shrub, which can be an early successional or permanent condition depending upon hydrology, habitat conditions include shrub density and shrub-herbaceous interspersion.

Table 5. Priority habitat features and associated focal species for conservation in riparian habitats in the Columbia Plateau Landbird Conservation Planning Region.

3. Unique Habitats

Landbird conservation is also directed toward several unique habitats in the Columbia Plateau (Table 6). In Aspen, the conservation emphasis is the presence of large trees and snags with some regeneration. In Agricultural Fields, the emphasis is for mesic conditions. In Juniper Woodland, the emphasis is mature juniper trees with some regeneration. In Cliffs and Rimrock, the emphasis is protected (undeveloped) foraging areas. In Mountain Mahogany, the emphasis is large diameter trees with some regeneration.

Table 6. Priority habitat features and associated landbird species for conservation in unique habitats of the Columbia Plateau Landbird Conservation Planning Region.

CHAPTER 6. LANDBIRD CONSERVATION

initiate conservation actions in accordance with the ecological potential of the site (i.e., within the framework of potential vegetation and natural ecosystem processes),

emphasize conservation within high priority designated conservation areas and where opportunities exist (i.e., receptive land owners and land managers), and

emphasize conservation at multiple scales such that habitat conditions for one or a few species are nested within a landscape that provides a mosaic of conditions for multiple species.

Meeting the goal of healthy landbird populations in the Columbia Plateau begins with the maintenance and restoration of properly functioning shrub-steppe and riparian ecosystems. Currently, considerable emphasis is being placed on restoration of these habitats to some semblance of presettlement conditions (approximately 1850). It is important to recognize that habitat alterations during restoration activities may temporarily or permanently displace landbird species currently using those areas. However, most degraded habitats tend to support habitat generalist species that are usually widespread and fairly common and not of high conservation concern. Because of the degree of loss and degradation of these systems, restoration in many areas will be a long-term process. The vision and practical realities of this process are described in the following sections.

Each section begins with a brief overview of conservation issues, biological objectives, and general conservation strategies for each priority habitat. This is followed by a focal species account for several important habitat features or conditions, and biological objectives and conservation strategies to achieve the objectives. Assumptions upon which the biological objectives are based are stated, with suggestions for research or monitoring to provide data to refine and update biological objectives. Examples are given of other species expected to benefit from management for each focal species, although conservation of these species is not dependent upon or synonymous with conservation of focal species.

For each focal species, information on habitat relationships was generally limited to data from eastern Oregon and Washington and southern Idaho because habitat types and management are unique relative to other areas. When little data were available from this region, occasional references were used from elsewhere in western North America.

A. Shrub-steppe

Shrub-steppe is the dominant habitat within the planning unit. The steppe component is scattered in small patches, except historically was dominated by the relatively large Palouse Prairie in eastern Washington. Shrub-steppe is a relatively xeric habitat that is dominated by shrubs, especially sagebrush, or co-dominated by shrubs and perennial bunchgrasses. The most common shrub species in the Columbia Plateau is big sagebrush, and several sagebrush obligate bird species are closely associated with big sagebrush. Other types of sagebrush and other shrubs can be locally dominant. Generally, the species of sagebrush or shrub is less important to landbirds than its height, foliage density, cover, and distribution across the landscape (Paige and Ritter 1999). In a shrub-steppe understory, one or more perennial bunchgrass species are usually dominant. Additionally, a wide array of forbs are important herbaceous components, although cover of those species today has been greatly diminished by a long-term history of livestock grazing and invasive competitors. A summary of the habitat features important to shrub-steppe landbirds is presented in Appendix C.

The implementation strategy for conservation of shrub-steppe birds uses a habitat "block" approach in which the emphasis is on maintaining large patches of quality habitat to support bird populations, especially area-sensitive species such as sage grouse and sage sparrow. To facilitate this approach, Shrub-steppe Bird Conservation Areas (SSBCAs) were designated (Appendix B) to take advantage of existing areas (large or small) where habitat conditions are or could be suitable, and where ownership and/or management are potentially compatible with landbird conservation (e.g., Hanford Reservation, sage grouse management areas, TNC preserves, wilderness areas). Depending on ecological potential and management focus, conservation actions within SSBCAs may emphasize management to maintain or provide a mosaic of conditions for multiple priority species or management actions directed towards one or a few species.

1. Conservation Issues (Shrub-Steppe):

there are a substantial number of obligate and semi-obligate landbird species, thus threats to the habitat jeopardize the persistence of these species

extensive permanent habitat conversions of shrub-steppe (e.g., approximately 60% of shrub-steppe in Washington [Dobler et al. 1996]) to other uses (e.g., agriculture, urbanization)

fragmentation of remaining tracts of moderate to good quality shrub-steppe habitat

habitat degradation from intensive grazing and invasion of exotics, particularly annual grasses such as cheatgrass and woody vegetation such as Russian olive

loss and degradation of properly functioning shrub-steppe ecosystems where there is encroachment of urban and residential development

most of the remaining shrub-steppe in Washington is in private ownership (57% [M. Vander Haegen pers. comm.])

best sites for healthy sagebrush communities (deep soils, relatively mesic conditions) are also best for agricultural productivity; thus, past losses and potential future losses are great

loss of big sagebrush communities to brush control

loss and reduction of cryptogamic crusts, which help maintain ecological integrity of shrub-steppe communities

conversion of Conservation Reserve Program (CRP) lands back to cropland

hostile landscapes, particularly those in proximity to agricultural and residential areas may have high density of nest parasites (brown-headed cowbird) and domestic predators (cats), and may be subject to high levels of human disturbance

agricultural practices that cause direct or indirect mortality and/or reduce bird productivity

fire management, either suppression or over-use

invasion and seeding of crested wheatgrass which reduces habitat availability

2. Biological Objectives (Shrub-Steppe):

• Institutionalize a policy of "no net loss" of shrub-steppe habitat (i.e., discourage loss and conversion of habitat, but when unavoidable, mitigate with equal or greater restoration efforts).
• Maintain existing areas of moderate to high quality shrub-steppe vegetation, and actively manage to promote their sustainability.
• Initiate actions to enhance size and connectivity of existing quality shrub-steppe patches (i.e., reduce fragmentation).
• Initiate actions to avoid or minimize further degradation of shrub-steppe habitat (e.g., reduce, eliminate or better manage livestock grazing).
• Initiate actions to improve quality of degraded shrub-steppe habitat through appropriate management (see Conservation Strategies throughout the plan).
• Maintain cryptogamic crusts where they occur, and seek ecologically appropriate sites for restoration to ensure proper functioning native plant communities.
• Maintain sites dominated by native vegetation and initiate actions to prevent infestations of exotic vegetation.
• Encourage restoration of agricultural lands to native cover types through acquisition, easement, or incentive programs.
• Increase habitat for grassland-associated species by managing non-native grasslands (e.g. agricultural lands, inactive grasslands such as CRP and fallow fields) as suitable habitat where biologically appropriate (i.e., where viable landbird populations can be maintained).
• Where ecologically appropriate in large patches of sagebrush habitat (e.g., watershed, Shrub-Steppe Bird Conservation Area, sage grouse management unit, etc.), initiate actions to maintain or provide:

• >50% of the landscape in a mid- to late-seral stage with canopy cover >15%

• at least one contiguous tract >400 ha (1,000 ac) with high quality conditions (see sage grouse and sage sparrow species accounts)

• <10% of the landscape as hostile habitat (e.g., developed areas with human habitation, intensively managed agricultural lands)

• In conjunction with conservation efforts described in the Idaho Landbird Conservation Plan (Ritter 2000) and the Nevada Landbird Conservation Plan (Neel 1999), reverse declining population trends in the Columbia Plateau BBS Region for six shrub-steppe species (see Table 2) to achieve stable populations (non-significant trends of <2%/year) or increasing populations within the next 10 years (by 2010); while maintaining stable or increasing populations for other shrub-steppe species.

Assumptions/Rationale: "No net loss" includes permanent conversion or degradation that compromises the ecological integrity of the habitat and/or reduces its suitability for our focal species. Natural events (e.g., wildfire) and some restoration activities (e.g., prescribed fire) that result in short-term "loss" are not considered here. Hostile habitat should not exceed 10% in order to minimize potential impacts of fragmentation and adverse human-related effects (disturbance from increased activity, residences where feral cats and dogs are an issue).

Monitoring BBS trends provides a coarse means of assessing progress of conservation actions relative to populations with a known baseline. This is not intended to replace monitoring that should occur to track progress at specific locations where conservation actions occur. The objective for reversing declining BBS trends assumes that actions to improve habitat will occur throughout the planning area, and the success of those actions will be reflected through increased abundance of declining species on randomly located BBS routes. The objective to reverse declining population trends also assumes that conservation actions on the breeding grounds will positively affect landbird populations. This may not be the case for migratory birds subject to adverse impacts during migration and/or on the wintering grounds. When conservation actions do not result in a positive population response by a species, efforts should be made to assess the appropriateness of the conservation actions and/or the likelihood of factors outside of the breeding grounds negatively affecting populations.

3. Conservation Strategies (Shrub-Steppe):

These general recommendations are presented to support conservation of landbirds in shrub-steppe habitats. Additional management recommendations for landbirds in shrub-steppe habitats are included in Paige and Ritter (1999). Specific recommendations as described below for priority focal species should supercede those presented here if there is a direct conflict between recommendations.

Data Collection:

• Conduct community and species research to test the biological objectives described throughout this document.

• Establish permanent roadside and off-road censusing stations to monitor bird population and habitat changes.

• Study the role of fire, mowing, and other management treatments to maintain/improve habitat quality.

Research Coordination:

• Coordinate research activities between government and private lands, particularly on large tracts of shrub-steppe habitat in an agricultural matrix such as Yakima Training Center, Hanford Reservation, and Boardman Bombing Range.

Conservation Areas:

• Seek to expand shrub-steppe focal species distribution and abundance throughout the Columbia Plateau by establishing Shrub-Steppe Bird Conservation Areas (SSBCAs) and promoting their proper management (see Appendix B).

Acquisition/Restoration:

• Support partnerships that seek to acquire/restore native shrub-steppe habitat (e.g., TNC, State, BLM and private partnerships in the Moses Coulee/Beezley Hills area, Douglas County, Washington).

• Develop conservation agreements with private landowners to enhance the quality of shrub-steppe habitat.

• Seek to maximize contiguous area of shrub-steppe and thus minimize fragmentation. The larger the area, the greater the likelihood of maintaining populations of area-sensitive and large territory species such as sage sparrow and sage grouse.

• Develop a shrub-steppe "scorecard" for government and non-government use in prioritizing and evaluating habitat for landbirds. The scorecard should provide guidelines for rating the habitat at various scales (local, landscape).

• Use native species and local seed sources in restoration.

• Restore areas that were seeded in crested wheatgrass.

Timing of Activities:

• In agricultural lands, minimize or avoid field operations and recreational activities (e.g., ATV riding adjacent to fields) during the breeding season (April 15 - July 15).

Mowing/Harvesting/Burning: Mowing/haying affects grassland birds directly and indirectly. It may reduce height and cover of herbaceous vegetation, destroy active nests, kill nestlings and fledglings, cause nest abandonment, and increase nest exposure and predation levels (Bollinger et al. 1990). Studies on grasshopper sparrow have indicated higher densities and nest success in areas not mowed until after July 15 (Shugaart and James 1973, Warner 1992).

• Delay mowing, haying, or harvesting of grass-dominated fields as long as possible, preferably until after July 15.

• Space mowing or haying frequency as widely as possible to increase the probability of successful nesting.

• In areas with high cheatgrass fuel loads (primarily parts of the Columbia Basin subprovince), fire suppression should be considered when fire threatens large patches of sagebrush (Holmes and Geupel 1998).

Tilling: Tilling (disking, planting, cultivation) of agricultural fields may destroy active nests and cause mortality to nestlings or fledglings, particularly if the initial tilling is in May and birds have already initiated nesting in the residue of the field from the previous year. Minimum or no tilling will also increase foraging opportunities by providing habitat for insect prey.

• Where possible, use no-till practices or conduct tilling prior to April 15 or after July 15.

Grazing: Poorly managed grazing may negatively affect habitat by altering species composition, reducing residual vegetation, inhibiting vegetation recruitment, and increasing encroachment of noxious weeds. Grazing may not adversely impact vegetation if relatively light pressure is rotated between pastures and deferred on an annual and seasonal basis.

• Implement grazing practices that are consistent with growth of native plants and forbs. This may include increasing rest cycles in rest-rotation systems, and/or deferring grazing until bunchgrasses have begun to cure.

• Manage livestock numbers or time on rangeland to maintain the ecological integrity of the plant community through fencing exclusions or time management.

• Exclude livestock grazing from relatively pristine areas.

Insecticides/Herbicides: Use of insecticides can reduce the insect food base for many bird species. Use of herbicides can reduce cover and indirectly affect the insect food base.

• Minimize or discontinue use of pesticides wherever possible.

• Practice procedures in Integrated Pest Management (described in ORS 634.122) for reduced destruction of non-target insects.

• Encourage biological controls rather than chemical controls wherever possible.

• Treatments should be followed by restoration activities.

• Limit the application of herbicides to invasive non-native species, and use in conjunction with habitat enhancement projects which include long-term solutions to control future infestations.

Uncultivated Areas: Uncultivated areas (e.g., inter-agriculture circles) provide habitat diversity within large expanses of cultivation. Some species may use uncultivated areas as refugia or as nesting habitat (A. Holmes unpubl. data).

• Provide uncultivated herbaceous areas within or adjacent to cultivated fields to provide habitat diversity and potential nesting habitat for some landbirds.

• Avoid spraying or mowing uncultivated herbaceous vegetation within or adjacent to cultivated fields (e.g., fence rows, roadsides, and untillable land such as rocky soils).

• Establish healthy stands of desirable native vegetation adjacent to irrigated fields to avoid the spread of noxious weeds.

Prioritization: All actions to acquire, maintain, enhance, or subsidize lands for bird conservation should consider the following factors:

• proximity to large contiguous tracts of good quality shrub-steppe

• proximity to populations of target priority/focal species

• proximity to a designated SSBCA

• sites free of or most resistant to cheatgrass invasion or dominance (i.e., higher moisture regime, >30 cm [12 in]/year)

• benefit to multiple shrub-steppe species

• risk of habitat loss to development or conversion to unsuitable habitat

• quality of the habitat - existing and potential

• compatibility of current and projected adjacent land uses

• uniqueness of the site in a local and regional context

• the likelihood of securing the land for conservation

Incentives/Programs: Economic incentive-based programs (new and old) are likely to be most successful in reaching the greatest number of private landowners to increase the land base of suitable shrub-steppe bird habitat.

• Increase the amount of land under incentives programs for wildlife habitat, targeting land within or adjacent to SSBCAs.

• Support existing programs and develop new economic incentive programs to solicit conservation and management agreements with private landowners to certify their land as a SSBCA.

Education/Outreach:

• Develop brochures or other educational materials for private landowners describing shrub-steppe values and management strategies to incorporate with farming practices that will maintain forage value and provide habitat for landbirds and other wildlife.

• Develop criteria to be incorporated into NRCS scorecards for their incentive programs to maximize benefits to landbirds.

• Support cooperative extension research, education, and workshops that demonstrate and promote the economic benefit of sustainable grazing and farming practices and also benefit landbirds.

B. Steppe (Grasslands)

Conservation Focus: Native Bunchgrass Cover

Focal Species: Grasshopper Sparrow (Ammodramus savannarum)

According to the ICBEMP terrestrial vertebrate habitat analyses, historical source habitats for grasshopper sparrow within our planning unit occurred primarily along the eastern portions of the Columbia Plateau ERU and the northern portion of the Owyhee Uplands ERU with a small amount in the northern portion of the Great Basin (Wisdom et al. in press). Within this core of historical habitat, the current amount of source habitat has been reduced dramatically from historical levels by 91% in the Columbia Plateau and 85% in the Owyhee Uplands. Within the entire Interior Columbia Basin, overall decline in source habitats for this species (71%) was third greatest among 91 species of vertebrates analyzed (Wisdom et al. in press).

Populations:

Anecdotal:

• may have expanded range in eastern Washington from historical occurrence only in southeastern corner of the state (Jewett et al. 1953)

Breeding Bird Survey (Sauer et al. 1999):

• Columbia Plateau Region: non-significant long-term (1966-1998) declining trend of 0.5%/year, and non-significant short-term (1980-1998) increasing trend of 1.1%/year

Habitat Relationships:

Anecdotal:

• native bunchgrass with low shrub cover and agricultural grasslands (e.g., hayfields, pastures, CRP) with intermediate grass height

• present in most CRP lands older than five years in southeastern Washington (M. Denny pers. comm.)

• semi-colonial nester

Morrow County, Columbia Basin, Oregon (Janes 1983):

• occupied relatively undisturbed native bunchgrass communities dominated by Agropyron spicatum and/or Festuca idahoensis, particularly north-facing slopes containing the lupine Lupinus leucophilus

Boardman Bombing Range, Columbia Basin, Oregon (Holmes and Geupel 1998):

• most abundant species in moderately grazed and ungrazed bunchgrass habitat type; no significant difference between the two

• perennial bunchgrass cover strongest predictor of its presence

• abundance positively associated with bunchgrass cover, and total herbaceous cover

• abundance negatively associated with shrub cover and density, sagebrush cover and density, open ground, and number of sagebrush stems >2.5 cm

• proportional nest success 62% (n=37), Mayfield estimates 46%; 36 of 37 nests at base of perennial bunchgrass

Columbia Basin, Washington, 1988-1990 (Dobler et al. 1996):

• only occurred in loamy 6-9" and sandy 6-9" range condition sites, and most abundant in the former

• no significant relationship with vegetation type (i.e., shrubs, perennial grasses, or annual grasses)

Columbia Basin, Washington 1991-1993 (Vander Haegen et al. 2000):

• only significant relationship was with percent cover perennial grass

• more abundant in loamy soil type than sandy or shallow soils, but not significantly different

• similar abundance in good, fair, and poor range class conditions

Conservation Issues:

These are specific to grasshopper sparrow; see page 25-26 for general Conservation Issues in shrub-steppe.

conversion of bunchgrass habitat to agriculture

alteration of bunchgrass habitat from intensive grazing and exotic grass and forb invasions (Quigley et al. 1996)

vulnerable because of high use of agricultural habitats (e.g., CRP) which are unreliable from year to year

shrub encroachment on grasslands from overgrazing and fire suppression

early season mowing of hayfields and similar agricultural lands may result in nesting failure and reduced productivity

may be area-sensitive (Herkert 1994); large tracts of habitat more likely to support populations

Biological Objectives:

Habitat:

• Columbia Plateau: Where ecologically appropriate, initiate actions in native grasslands to maintain or provide the following conditions:

• native bunchgrass cover >15% and comprising >60% of the total grass cover

• tall bunchgrass (i.e., >25 cm [10 in] tall)

• native shrub cover < 10%

• Columbia Plateau: Manage non-native and agricultural grasslands (e.g., CRP) as potential habitat within the following conditions:

• grass-forb cover >90%

• shrub cover <10%

• variable grass heights between 6-18 in (15-46 cm)

• Columbia Plateau: Where ecologically appropriate at the landscape level, provide conditions described above in patches >40 ha (100 ac) or multiple smaller patches >8 ha (20 ac) within a mosaic of suitable grassland conditions.

Population:

• Columbia Plateau BBS Region: Maintain stable or increasing population trends over the next 10 years (by 2010).

Assumptions/Rationale: "Ecologically appropriate" refers to the potential vegetation of the site, considering hydrology, soils, topography, and natural ecosystem processes. The objective for native bunchgrass and shrub cover in steppe grasslands was based on Holmes and Geupel (1998). The objective for bunchgrass height was subjectively developed based on the collective experience of several individuals. The objectives for agricultural grasslands were from westside habitats (Altman 1999). A diverse community of native bunchgrasses and forbs provides nesting cover and insect and seed food resources. Blocks of habitat >100 acres can provide for at least 20 pairs, which may be necessary to maintain a small population for this potentially area-sensitive species (see Conservation Issues) even if area is not linked with other grasshopper sparrow populations.

Despite relatively stable trends, grasshopper sparrow use of agricultural grasslands makes it vulnerable when changes in agricultural practices occur. Monitoring BBS trends provides a coarse means of assessing progress of conservation actions relative to populations with a known baseline. This is not intended to replace monitoring that should occur to track progress at specific locations where conservation actions occur. The objective for stable or increasing BBS trends assumes that actions to improve habitat will occur throughout the planning area, and the success of those actions will be reflected through increased abundance of grasshopper sparrow on randomly located BBS routes.

Conservation Strategies:

These are specific to grasshopper sparrow; see pages 27-30 for general Conservation Strategies in shrub-steppe.

A high priority area for grassland and grasshopper sparrow conservation is the Palouse Prairie.

Revegetate whenever possible to native bunchgrass cover.

Eliminate, defer, or actively manage grazing intensity to maintain appropriate grass cover; this may include fall and winter grazing (but not spring and summer), and/or rotational systems where some fields not grazed at all.

High priority areas for conservation are the Columbia Basin and Great Basin subprovinces

Avoid placing agricultural grass fields adjacent to or near native bunchgrass habitat where birds may be pulled into agricultural fields that potentially function as population sinks.

Seek to provide the largest tracts of suitable habitat possible.

Delay mowing of suitable habitat until after July 15.

Where treatments are occurring in grasslands (e.g., burning, mowing, chemical applications) leave adjacent untreated areas to maintain a population of associated birds until treated areas become suitable habitat again.

Species to Benefit: The primary species to benefit from native bunchgrass cover would be other grassland species such as long-billed curlew, western meadowlark, savannah sparrow, vesper sparrow, horned lark, burrowing owl, northern harrier, and short-eared owl.

Information Needs:

1. Data are needed on all aspects of nesting ecology, particularly the relationship between grazing and productivity.

2. Data are needed on whether cowbirds are impacting productivity and, if so, in what landscape and land use context.

3. Is grasshopper sparrow area-sensitive in native habitats? If so, what are the conditions under which productive populations can be maintained?

C. Steppe-Shrubland

Conservation Focus: Interspersion Tall Shrubs and Openings

Focal Species: Loggerhead Shrike (Lanius lodovicianus)

According to the ICBEMP terrestrial vertebrate habitat analyses, historical source habitats for loggerhead shrike included all three ERUs within our planning unit (i.e., Columbia Plateau, Northern Great Basin, and Owyhee Uplands) (Wisdom et al. in press). Within this core of historical habitat, declines in source habitats occurred in the Columbia Plateau (25%), and Owyhee Uplands (13%), and an increase occurred in the Great Basin (11%). However, declines in big sagebrush (e.g., 50% in Columbia Plateau ERU), which likely is higher quality habitat, are masked by an increase in juniper sagebrush (>50% in Columbia Plateau ERU), which may be reduced quality habitat. Within the entire Interior Columbia Basin, overall decline in source habitats for this species was 20%, fueled largely by over 57% of watersheds showing declines in source habitats in the Upper Snake River ERU (Idaho) (Wisdom et al. in press).

Populations:

Anecdotal:

• noticeable declines in the Lower Columbia Basin; very low recruitment into populations throughout southeastern Washington (M. Denny pers. comm.)

Breeding Bird Survey (Sauer et al. 1999):

• Columbia Plateau Region: highly significant (p<0.01) long-term (1966-1998) declining trend of 2.7%/year, and non-significant short-term (1980-1998) declining trend of 1.8%/year

Habitat Relationships:

Anecdotal:

• open habitat with interspersion of tall woody shrubs (e.g., sagebrush, bitterbrush) or trees (e.g., juniper) for nesting and open ground for foraging

• salt scrub and black greasewood communities in Great Basin (G. Ivey pers. comm.)

• nests in juniper trees on Cedar Mountain, Malheur County (M. Denny pers. comm.)

Columbia Basin, Washington, 1988-1990 (Dobler et al. 1996):

• abundance positively associated with density of big sagebrush

Columbia Basin, Washington, 1993-1994 (McConnaughey and Dobler 1994):

• optimal habitat (i.e., where highest densities occurred) was community of big sagebrush-hopsage-Sandberg bluegrass on Hanford Energy Reservation

Columbia Basin, Washington 1991-1993 (Vander Haegen et al. 2000):

• abundance significantly higher with sandy soil types over loamy and shallow soils

• abundance not significantly greater in any of the three classes of range condition (good, fair, poor)

Boardman Bombing Range, Columbia Basin, Oregon, (Holmes and Geupel 1998):

• nests (n=156) predominantly in sagebrush (91.6%, n=143) with others in Russian thistle (2.6%, n=4), juniper (2.6%, n=4), ornamental shrubs (1.9%, n=3), and others (1.2 %)

• proportional nest success 45% (n=152); Mayfield estimates 36% (n=146)

Hanford Energy Reservation, Columbia Basin, Washington (Poole 1992):

• selected tall, dense live shrubs for roosts, slightly shorter live shrubs for nests, and dead shrubs for perches

• optimal habitat late-seral big sagebrush or antelope bitterbrush within a mosaic of openings and patches of tall shrubs

• mean nest shrub height 178.5 cm and mean sagebrush nest shrub height 164.4 cm

• nest areas

mean shrub cover tall species 6%

mean sagebrush cover 9%

mean shrub height 121 cm

mean sagebrush height 115 cm

annual grass cover 13%

bare ground 40%

Yakima Training Center, Columbia Basin, Washington (Leu 1995):

• tallest shrubs important as fledgling roost sites, nest shrubs also tall (>1 m), above mean shrub height but below tall shrub height

• foraging success decreased with increasing amount of cheatgrass cover

Northern Great Basin, southeastern Oregon, 1977-1979 (Wiens and Rotenberry 1981):

• abundance significant positive association with rock cover (p<0.001)

• abundance significant positive association with hopsage cover (p<.01), budsage cover (p<.05), and cottonthorn cover (p<.001)

Southwestern Idaho (Woods and Cade 1996):

• nests in shrubs 3 to 6 ft tall (1 to 2 m)

• nests found in sagebrush (60%), bitterbrush (20%), and greasewood (12%)

Crooked River National Grasslands, High Lava Plains, 1997-1999 (R. Gerhardt unpubl. data):

• nests (n=91) 78% in juniper, 12% in bitterbrush, 10% in sagebrush

• mean nest height (n=91) 118 cm (range 20-290 cm)

• proportional nest success (n=83) 67%

• mean 4.8 young/successful nest; 3.2 young/nest attempt

• density 3.4 breeding pairs/sq km (8.5/sq mi)

Conservation Issues:

These are specific to loggerhead shrike; see page 25-26 for general Conservation Issues in shrub-steppe.

habitat loss from conversion to agriculture

habitat loss from frequent fires in cheatgrass dominated sites

long-term heavy grazing may ultimately reduce prey habitat and degrade the vegetation structure for nesting and roosting

foraging sites, particularly for young birds, need to have open ground (bare and/or cryptogamic crusts) or little vegetative cover (Leu 1995); invasion of exotic annual grasses, particularly cheatgrass, has been detrimental

may suffer sublethal effects (e.g., reduced reproductive output) from certain insecticides (Anderson and Duzan 1978, Yosef 1996)

use of insecticides (e.g., for grasshopper control) may reduce prey base (Yosef 1996)

Biological Objectives:

Habitat:

• Columbia Plateau: Where ecologically appropriate, initiate actions in steppe-shrubland habitat to maintain or provide the following conditions:

• late-seral big sagebrush or bitterbrush with patches of tall shrubs (mean height of shrubs >1 m [39 in])

• <15% tall shrub cover (non-rabbitbrush)

• herbaceous cover <20% and dominated by native species

• mean open ground