leads to high occurrence. Wildfire - OR, ID, UT, WY, MT Big sagebrush Bird counts Flushing bird counts Brewer’s Sparrow only found on unburned sites, none on burned. Welch 2002 Wildfire - Central UT Big sagebrush, cold desert Bird density (territories/16 ha) Bird census with spot-mapping method and flush technique Brewer’s Sparrow densities were much lower on the burned site and would have likely been entirely absent without sagebrush islands. Castrale 1982 Prescribed burning - Southcentral WY (Stratton Sagebrush Ecological Research Site) Sagebrush habitats including mountain big sagebrush and black sagebrush interspersed with antelope bitterbrush Density (birds/ha) Line sampling transect with stratified random design Positive correlation with local tall shrub cover. Large, contiguous burns translated into near complete avoidance. Proximity to unburned plots may be more important than retention of large unburned swaths. Erickson 2011 Prescribed burning +/- Eastern OR High-elevation mountain big sagebrush Bird abundance 5-minute surveys Highest abundance at unburned plots with decreasing abundance at higher burn severities. Difference between low severity (<30%) and unburned was Holmes 2007
not statistically significant. Prescribed burning +/- Upper Snake River plain, ID Big sagebrush Bird density (territories/km2) Territories estimated with spot-map method and census over 5 years Initial decline for 2 seasons but more than doubled after; higher densities than control within 5 years. Petersen and Best 1987 Prescribed burning - Southeastern ID Big sagebrush Activity budget Territories delimited using flush technique and nests found with rope-dragging within territories. Prefer foraging sites with greater coverage, so burns that reduce sagebrush coverage reduce foraging. Affects females more. Winter 1984 Grazing NC Central MT Sagebrush ecosystem Abundance Dependent transect surveys and nest searches. Comparison of traditional grazing and rest-rotation grazing, not grazed vs. ungrazed. No difference in abundance between grazed plots. Dreitz et al. 2015 Grazing NC / - Southcentral WY (Stratton Sagebrush Ecological Research Site) Sagebrush habitats including mountain big sagebrush and black sagebrush interspersed with antelope bitterbrush Density (birds/ha) Line sampling transect with stratified random design A 44% greater density of Brewer’s Sparrow in late grazing pasture compared to early and grazing. Erickson 2011 burn, summer
Grazing - Northern Plains Shrub steppe Density index (pairs/min x 103) One bird census per 65 ha plot using hollow square technique On shrub steppe, decreasing density as grazing pressure increases, but still more abundant than most species. Pattern not consistent in other subregions. Kantrud and Kologiski 1983 Grazing - Northern CO (Central Plains Experimental Range) Shortgrass prairie Breeding bird pairs per 20 acres Literature review No breeding pairs on summer-grazed plots. Some pairs on winter-grazed, but fewer on heavily grazed plots compared to lightly grazed plots. Ryder 1980 Grazing (sheep) NC Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in 4-ha grid. Effects of grazing inconclusive; crested wheatgrass occurrence the driving factor. Reynolds and Trost 1980 Grazing NC Great Basin (CA/NV) Various habitat types including low sagebrush and big sagebrush Bird abundance One-mile census Major decrease in low sagebrush; inconclusive in big sagebrush habitats. Prefer low grass, not bare ground? Page et al. 1978 Grazing - Central Plains Experimental Range, northern CO Shortgrass prairie Number observed Plot counts, roadside counts, nest searches, territory determinations, and specimen collections. Brewer’s Sparrows restricted almost entirely to winter use pastures that contained fourwing saltbush. Giezentanner 1970
treatment, Mechanical thinning + Northeast UT cover Density (birds/ha) Applied experimental mechanical thinning to cover. 2,400-m long-line transects in 4 600-m legs along cardinal bearings for bird surveys. Noticeable density increase in first year but effect slowing trended back to pre-treatment reference by year four. Norvell et al. 2014 Plowing / chaining NC Central UT Big sagebrush, cold desert Bird density (territories/16 ha) Bird census with spot-mapping method and technique Relatively high densities on chained plots indicated chaining did not reduce sagebrush enough to affect the species, or the habitat recovered within 4 years. Castrale 1982 removal (chaining) + Piceance Basin, CO Mature woodland Bird density Census using the spot-mapping method. No Brewer’s Sparrow at unchained plot. Chaining increased at recent treatment and then decreased through time. O’Meara et al. 1981 Juniper removal + Southern OR Sagebrush habitats Abundance Survey of all birds seen or heard at cut sites. Abundance continued to increase annually after conifer removal; benefits may not yet be fully realized as birds continue to recolonize cuts through time. Holmes et al. 2015
Juniper removal NC UT, NV, ID, OR Sagebrush and woodland ecotones Bird counts Point transects with distance sampling. Included both prescribed burns and adjacent mechanical juniper removal. Detected at all treatment plots but no changes significant or consistent in trend. et al. 2014 Juniper removal + Central OR Mountain big sagebrush successional gradient Bird density (birds/ha/yr) Compared vegetative structure and bird communities among 4 successional states Bird communities observed across landscape types, impacts surmised from results. Strong preference for shrub-steppe habitats and reduced density in post-burn grassland and mid-successional juniper. Reinkensmeyer et al. 2007 Juniper removal + Southeastern OR Sagebrush Steppe, mountain big sagebrush Occurrence Fixed-radius point count Abundance and occurrence positively correlate with sagebrush cover and height and negatively correlate with juniper presence Noson et al. 2006 Pinyon removal NC Great Basin, Mono County, CA Pinyon pine woodland with sporadic juniper that merges into sagebrush with Counts counts and census, nest searching, and territory spot mapping Breeding on both control and treatment plots. However, increasing pinyon density results in Woolley and Heath 2006
decreasing elevation fewer BRSP detections. Invasive species – crested wheatgrass - Central NV Sagebrush control sites and crested wheatgrass treatment sites Relative bird abundance Two parallel transects with 5 circular plots at each site Seeded plots have reduced densities, though comparatively high densities to other birds observed. McAdoo et al. 1989 Invasive species – crested wheatgrass - Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in 4-ha grid. No Brewer’s Sparrow occurrence on grazed or ungrazed plots seeded with crested wheatgrass. Reynolds and 1980 Mine reclamation - South Central WY steppe with saltbrush and greasewood interspersed. Bird Density (birds/ha/census day) 73 censuses with transects through native and reclaimed habitats Reclaimed sites dominated by common halogeton (Halogeton glomeratus). Abundant on native site but rarely encountered on reclaimed site. Krementz and 1982 Herbicide NC East-central CA, northwest of Truckee. Shrubby, brush field with grasses and scattered Jeffrey pine Estimated population size per 40 ha Spot map technique and nest location Treatment did not affect avian species composition, population size, or relative abundance. Brewer’s Sparrow not impacted. Beaver 1976 Herbicide - Southcentral WY (Stratton Sagebrush Big sagebrush Density (birds sighted/10 acres2) Census and nest observation. Herbicide 2,4-D Bird densities were 67% lower 1 year after Schroeder and Sturges 1975
Hydrology Area) spraying and 99% lower two years later. No nests were observed on the sprayed area. Herbicide - / NC Central MT Estimated breeding numbers Birds censused using technique. Five 2,4-D herbicide treatments. The only notable decline was on the total kill spray plot, not partial kill plots. Best 1972
3: 2015). The Sagebrush Sparrow is a migratory sagebrush obligate songbird that nests in sagebrush shrublands. The Sagebrush Sparrow has a global population of 4.7 million birds and its breeding range covers more than 1 million square kilometers (Figure 3). The species shares much of its breeding range with the greater sage-grouse: 43% of the Sagebrush Sparrow’s range overlaps that of the grouse (Table 1). The Sagebrush Sparrow is listed as a species of concern in three western states: Wyoming, Montana, and Washington (Table 2). Like many sagebrush songbirds, the Sagebrush Sparrow is declining throughout its range (the Sagebrush Sparrow analysis includes data for the Bell’s Sparrow (Amphispiza belli) which was split from the Sagebrush Sparrow in 2013.) The species is declining most rapidly in the Southern Rockies/Colorado Plateau region and the northern Great Basin in southeastern Oregon and southern Idaho (Table 6, Figure 4). At the state level, the population decline is greatest in Idaho, Oregon, and Colorado, where the species is estimated to be losing more than four percent of its population annually. The data from Idaho and Colorado, however, contain data deficiencies that may affect the accuracy of the trend estimate. The 2012 PIF plan (Rosenberg et al. 2016) classified the Sagebrush Sparrow’s breeding threats as a 3, denoting a slight to moderate decline in the future suitability of its breeding conditions (Panjabi et al. 2012). 4: (1966-2013)
Prescribed burning NC Upper Snake River plain, ID Big sagebrush Bird density (territories/km2) Territories estimated with spot-map method and census over 5 Along with Brewer’s Sparrows, sage sparrows represented nearly 90% of total birds on plots. Densities varied by years for both treatments, but unaffected by fire. Prescribed burning NC Southeastern ID Big sagebrush Activity budget Territories delimited using flush technique and nests found with rope-dragging within territories. Little change in foraging habits after fire, but do become more generalized feeders. Males expend more energy in territorial maintenance post-burn Grazing (sheep) NC Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in 4-ha grid. Slight increase in number of nests in grazed plots, but difference small enough to be inconclusive. Mechanical thinning - Northeast UT Sagebrush-steppe cover Density (birds/ha) Applied experimental mechanical thinning to shrub cover. 2,400-m transects in 4 600-m legs along cardinal bearings for bird surveys. Decreased abundance in first year post-treatment and did not recover. Herbicide - Southern OR rangeland Density (individuals/km2) Recorded all sight and sound observations along 610 m linear strip transects. Herbicide 2,4-D treatments. Sage sparrow abundance did not decrease in first year, but gradually decreased in following 2 years. Juniper removal + Central OR Semi-arid, upland plant communities Abundance (birds/ha/yr), diversity Sampled avian and veg communities in 4 cover types: post-burn grassland, shrub-steppe; western juniper; old-growth western juniper Highest density in but still occur in juniper at lower density. No occurrence in old growth juniper. Pinyon removal NC Great Basin, Mono County, CA Pinyon pine woodland with sporadic juniper Counts Point counts and census, nest searching, and territory spot mapping Detected just beyond treatment during nearly every census, but did not
that merges into sagebrush with decreasing elevation hold territory in plots until after fledgling occurred. Likely bred off plot and moved onto plot after fledgling. Juniper removal + Central OR Mountain big sagebrush successional gradient Bird density (birds/ha/yr) Compared vegetative structure and bird communities among 4 successional states Bird communities observed across landscape impacts surmised from results. Strong preference for shrub-steppe habitats and reduced density in post-burn grassland and juniper. Juniper removal NC / + UT, NV, ID, OR Sagebrush and woodland ecotones Bird counts Point transects with distance sampling. Results indicate that management treatments that residual woodland cover that are not adjacent to extensive sagebrush stands are unlikely to establish Sagebrush Sparrow population. Invasive species – Cheatgrass - Central WA Sagebrush Steppe interspersed with disturbed and invaded patches Bird Count / frequency of occurrence Walking transects Sage sparrows most common in areas with big sagebrush and least common in burned habitats invaded by Cheatgrass. Invasive species – crested wheatgrass - Central NV Sagebrush control and crested wheatgrass treatment sites Relative bird abundance Two parallel transects with 5 circular plots at each site Abundance higher at sagebrush control sites. Abundance directly correlates with shrub cover. However, abundance increased in time as sagebrush reestablished. Invasive species – crested wheatgrass - Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in 4-ha grid. No sage sparrow occurrence is grazed or ungrazed plots seeded with crested wheatgrass.
Wildfire - Central UT Big sagebrush, cold desert Bird density (territories/16 ha) Bird census with spot-mapping method and flush technique Sage Thrasher was only found in habitat patches containing the largest shrubs. Unburned islands could support thrasher on burned plot. Castrale 1982 Prescribed burning NC UT, NV, ID, OR Sagebrush and woodland ecotones Bird counts transects with distance sampling. Included both prescribed burns and adjacent mechanical juniper removal. Detected at all treatment plots but no changes significant or consistent in trend. Knick et al. 2014 Prescribed burning - Southcentral WY (Stratton Sagebrush Ecological Research Site) Sagebrush habitats including mountain big sagebrush and black sagebrush interspersed with antelope bitterbrush Density (birds/ha) Line sampling transect with stratified random design Positive correlation with local tall shrub cover. Larger, more contiguous burns translated into near complete avoidance by Sage Thrasher. Erickson 2011 Prescribed burning - Eastern OR High-elevation mountain big sagebrush Bird abundance 5-minute surveys Sage Thrasher occurred in abundance on sites largely or completely burned compared to sites outside burn or within unburned islands. Holmes 2007
treatment Prescribed burning NC Upper Snake River plain, ID Big sagebrush Bird density (territories/km2) Territories estimated with spot-map method and census over 5 years Sage Thrasher populations remarkably stable on both treatments, showing no response to fire. Petersen and Best 1987 Grazing NC Southcentral WY (Stratton Sagebrush Ecological Research Site) Sagebrush habitats including mountain big sagebrush and sagebrush interspersed with antelope bitterbrush Density (birds/ha) Line sampling transect with stratified random design No pasture effects were evident for Sage Thrasher. Erickson 2011 Grazing - Northern Great Plains Shrub steppe Density index (pairs/min x 103) One bird census per 65 ha plot using hollow square technique Highest density on low intensity grazing plots; higher density on high intensity plots than moderately grazed plots. Kantrud and Kologiski 1983 Grazing (sheep) NC Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in grid. Slight increase in number of in grazed plots, but difference small enough to be inconclusive. Reynolds and Trost 1980 Mechanical thinning - Northeast UT cover Density Applied experimental mechanical thinning to shrub cover. 2,400-m long-line transects in 4 600-m legs along Decreased abundance in first year and did not recover. Norvell et al. 2014 ha
cardinal bearings for bird surveys. Plowing / chaining - Central UT Big sagebrush, cold desert Bird density (territories/16 ha) Bird census with spot-mapping method and technique Sage Thrasher was only found in habitat patches containing the largest shrubs. Castrale 1982 Juniper removal + Central OR Mountain big sagebrush successional gradient Bird density (birds/ha/yr) Compared vegetative structure and bird communities among 4 successional states Bird communities observed across landscape types, impacts surmised from results. Strong preference for shrub-steppe habitats and reduced density in post-burn grassland and mid-successional juniper. Reinkensmeyer et al. 2007 Juniper removal + Southeastern OR Sagebrush Steppe, mountain big sagebrush Occurrence Fixed-radius point count Abundance and occurrence positively correlate with sagebrush cover and height and negatively correlate with juniper presence Noson et al. 2006 Juniper removal + Central OR Semi-arid, upland plant communities Abundance (birds/ha/yr), diversity Sampled avian and veg communities in 4 cover types: grassland, shrub-steppe; mid-successional western juniper; old-growth western juniper Highest density in shrub-steppe, but still occur in juniper at lower density. No occurrence in old growth juniper. Reinkensmeyer 2000
Pinyon removal NC Basin, Mono County, CA Pinyon pine woodland with sporadic juniper that merges into sagebrush with decreasing elevation Counts Point counts and census, nest searching, and territory spot mapping Increasing pinyon pine correlates with reduced thrasher occurrence, but limited occurrence at control or treatment. Not territorial on control plots, but observed on plot after fledgling. Woolley and Heath 2006 Invasive species – Cheatgrass - South Central WA Sagebrush Steppe interspersed with disturbed and invaded patches Bird Count / frequency of occurrence Walking transects Sage Thrasher nest in sagebrush shrubs and invasion by Cheatgrass that reduces shrub cover negatively impacts the species. Brandt and Rickard 1994 Invasive species – crested wheatgrass - Central NV Sagebrush control sites and crested wheatgrass treatment sites Relative bird abundance Two parallel transects with 5 circular at each site Sage Thrashers have affinity for shrub cover, and lower abundance on plots seeded with wheatgrass. McAdoo et al. 1989 Invasive species – crested wheatgrass - Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in grid. No Sage Thrasher occurrence is grazed or ungrazed plots seeded with crested wheatgrass. Reynolds and Trost 1980 Mine reclamation - South Central WY steppe with saltbrush and Bird Density (birds/ha/census day) 73 censuses with transects through native and Reclaimed sites dominated by common halogeton Krementz and Sauer 1982
11: "+" = " - " = "0" = "+ / - " = Treatment Response Location Habitat Response Variable Methods Notes Citation Wildfire - Northwestern Great Basin (NV) Mountain big sagebrush Density (individuals/km2) 5-minute point count surveys across burned and unburned plots Gray Flycatcher density on burned plots. After 20 years at burned plots, density only 17% of adjacent unburned plots. No clear recover trajectory. Holmes and Robinson 2013 Wildfire - Central Mountain big sagebrush successional gradient Bird density (birds/ha/yr) Compared vegetative structure and bird communities 4 successional states Bird communities observed across landscape impacts surmised from results. Strong preference for and juniper. Reinkensmeyer et al. 2007 Wildfire - Rocky Mountains Pinyon-juniper woodland N/A Literature Review The loss of cover may initially result in a negative response by the Gray Flycatcher. Saab et al. 2005 Wildfire - OR, ID, UT, WY, MT Big sagebrush Bird counts Flushing bird counts Gray Flycatcher only on unburned sites, none on burned. Welch 2002 Prescribed burning + North-central WA Ponderosa pine dominated mixed-conifer forest, east of the Cascades Multispecies site occupancy model 5-minute point counts Evidence that the Gray Flycatcher responded positively to the prescribed fire treatments. Russell et al. 2009 Grazing + Northeast NM Eastern slope of Sangre de Cristo Mtns. Low elev = Counts Random plot selection of grazed and post-grazing Mean detections were higher on grazed plots, but the results were not Goguen and Mathews 1998 growth
shortgrass prairie, high elev = P-J woodland plots in P-J woodland. tested statistical significance. Grazing + Great Basin (CA/NV) Various habitat including low sagebrush and big sagebrush Bird abundance One-mile strip census Did not occur in sagebrush habitats, but preferred grazed over ungrazed plots in Shadscale/Indian ricegrass and Nevada bluegrass/sedge habitat types. Page et al. 1978 Mechanical thinning - Northeast UT cover Density (birds/ha) Applied experimental mechanical thinning to shrub cover. 2,400-m long-line transects in 4 600-m legs along cardinal bearings for bird surveys. Density decreased in year and remained low compared reference for the duration of the study. Norvell et al. 2014 Juniper removal - Southern OR Sagebrush habitats Abundance Survey of all birds seen or heard at cut sites. Abundance continued to increase annually conifer removal; benefits may not yet be fully realized as birds continue to recolonize cuts through time. Holmes et al. 2015 removal - Multiple Multiple N/A Review of management in P-J woodlands Summary, no specific treatment actions. Manage for at least 13% canopy cover; retain snags and partially dead trees. Retain shrublands. Gillihan 2006
13: "+" = " - " = "0" = "+ / - " = Treatment Response Location Habitat Response Variable Methods Citation Wildfire - Great Basin (NV) Mountain big sagebrush Density 5-minute point count surveys across burned and unburned plots Significantly reduced density at burned plots. However, show a pattern of recovery, reaching 75% of unburned densities after years. Holmes and Robinson 2013 Wildfire + Central OR Mountain big sagebrush successional gradient Bird density (birds/ha/yr) Compared vegetative structure and bird communities among 4 successional states Bird communities observed across landscape types, impacts surmised from results. Highest density in post-burn grassland vegetative state. et al. 2007 Wildfire - Southeastern OR Sagebrush Steppe, mountain big sagebrush Occurrence Fixed-radius point count Abundance and occurrence positively correlate with sagebrush burned sites had low sagebrush cover compared to unburned. Noson et al. 2006 Wildfire - OR, ID, UT, WY, MT Big sagebrush Bird counts Flushing bird counts No Sage Thrashers found on burned sites, only unburned. Welch 2002 Prescribed burning - Southcentral WY (Stratton Sagebrush Ecological Sagebrush habitats including mountain big sagebrush and black Density (birds/ha) Line sampling transect with stratified random design Positive correlation with local tall shrub cover. Burn Erickson 2011
Research Site) sagebrush interspersed with antelope bitterbrush effects diminished somewhat through time Prescribed burn - Rocky Mountain National Park, CO Montane shrubland Density Distance sampling to estimate density at each site. Nest searching for behavioral cues by adults and flushing. 3-5 following the prescribed burns, towhee density and shrub cover were generally higher in unburned areas. Jehle et al. 2006 Fire/thinning + Multiple Southwestern conifer forests Counts Literature Review for thinning and burning In response to wildfire and overstory removal (high-severity treatment), the towhee cumulatively responded positively. Kalies et al. 2010 Grazing NC Southcentral WY (Stratton Sagebrush Ecological Research Site) Sagebrush habitats including mountain big sagebrush and black sagebrush interspersed with antelope bitterbrush Density (birds/ha) Line sampling transect with stratified random design No pasture effects were evident for Towhee. Erickson 2011 Grazing NC Northeastern NM Pinyon-juniper woodland Mean detections by plot and nesting success Point count method No observations of the bird of grazed only on ungrazed. However, result is insignificant and inconclusive due to infrequent observations. Goguen and Matthews 1998 Mechanical thinning NC Northeast UT Sagebrush-steppe Density Applied experimental mechanical No significant density changes post-treatment. Norvell et al. 2014
thinning to cover. 2,400-m long-line transects in 4 600-m legs along cardinal bearings for bird surveys. Juniper removal + Southern OR Sagebrush habitats Abundance Survey of all birds seen or heard at cut sites. Abundance continued to increase annually after conifer removal; benefits may not yet be fully realized as birds continue to recolonize cuts through time. Holmes et al. 2015 Juniper removal + Central OR Mountain big sagebrush successional gradient Bird density (birds/ha/yr) Compared vegetative structure and bird communities among 4 successional states Bird communities observed across landscape types, impacts surmised from results. Infrequent to no observations in landscapes with juniper. et al. 2007 Juniper removal + / - Southeastern OR Sagebrush Steppe, mountain big sagebrush Occurrence Fixed-radius point count Green-tailed Towhee showed a curvilinear relationship to juniper. Initial encroachment benefits the bird, but peaks at about 33% of landscape before negatively impacting the species Noson et al. 2006
Juniper removal + / NC OR Shrub-steppe Counts Mechanical shearing of juniper; bird census Green-tailed Towhee found after juniper removal, but low numbers of observations suggest the results may not be significant. Sabol 2005 Pinyon-juniper removal (chaining) + Piceance Basin, CO Mature pinyon-juniper woodland Bird density Census using the spot-mapping method. Towhee density highest in most recent chaining treatment. No occurrence in unchained woodland. O’Meara et al. 1981 Pinyon removal NC Great Basin, Mono County, CA Pinyon pine woodland with sporadic juniper that merges into sagebrush with decreasing elevation Counts Point counts and census, nest searching, and territory spot mapping High densities of Green-tailed Towhee on both treatment and control plots Woolley and Heath 2006 Pinyon-juniper expansion - Central Great Basin (NV) Pinyon-juniper woodland, sagebrush shrubsteppe, and riparian woodland Incidence at each point-count location 75- or 100-m fixed-radius point counts and boosted regression trees to model incidence Under a expansion scenario, models predict a 6% decrease in occupied area (summed incidence). Fleishman et al. 2014 Herbicide NC East-central CA, northwest of Truckee. Shrubby, brush field with grasses and scattered Jeffrey pine Estimated population size per 40 ha Spot map technique and nest location Treatment did not affect species composition, population size, or relative abundance. Towhee not impacted. Beaver 1976
14: 1966-2013. Region L 95% CI U 95% CI N California -2.95* -4.10 -1.81 146 Colorado -0.62 -1.92 0.62 69 Idaho — — — — Oregon 1.52 -0.33 3.33 32 Montana — — — — Nevada -0.62 -1.97 0.73 39 Utah -0.73 -2.43 0.92 63 Washington — — — — Wyoming -0.73 -2.05 0.59 90 Northern Rockies — — — — Southern Rockies/Colorado Plateau -1.03 -2.37 0.30 91 Basin -0.69 -1.64 0.27 148 Badlands and Prairie -1.81* -2.72 -0.94 90 Shortgrass Prairie -2.53* -3.49 -1.62 113 Western BBS -1.76* -2.39 -1.16 536 Continental -3.20* -3.49 -2.91 2050 * Statistically significant (credible interval does not span zero). — Values are not presented because of insufficient data. Many studies found that fire negatively impacted shrike habitat, though the species most likely has a mixed response depending on fire characteristics and other environmental factors. In many states, the BLM has adopted a fire suppression policy, which many land managers believe will improve shrike habitat (Pruitt 2000). Studies by Welch (2002), Humple and Holmes (2006), and Holmes and Robinson (2013) all found that fire in sagebrush habitats reduced nesting and bird density; however, low intensity, patch burns could also benefit the bird (Poole 1992). On the whole, grazing also tended to negatively impact shrike habitat, but the effect will vary by practice and location. Page et al. (1978) found no impact from grazing in low sagebrush; results were inconclusive in big sagebrush. In a low-shrub desert, Medin (1986) found no significant difference between ungrazed plots and heavy, late winter grazing plots; shrikes were infrequently observed at the heavy, early and middle winter grazing plots. Prescott and Collister (1993) found that Loggerhead Shrikes preferred undisturbed areas, but the study was not in
15: "+" = " - " = "0" = "+ / - " = Treatment Response Location Habitat Response Variable Methods Notes Citation Wildfire - Northwest NV (northwestern Great Basin) Mountain big sagebrush Density 5-minute count surveys across burned and unburned plots Did not compute density for the shrike, but occurred at 12 points, all unburned locations. Holmes and Robinson 2013 Wildfire - Northeastern OR Sagebrush Steppe Density, Mayfield estimate of nest successful territories, average territory, average nest Census and nest searching Shrike density was half of pre-fire density. Fire reduced nest survivorship. In year post-fire, reduced fledglings from successful territories. Humple and Holmes 2006 Wildfire - OR, ID, UT, WY, MT Big sagebrush Bird counts Flushing bird counts Compared burned versus unburned sites; no birds found at burned sites, though only 1 observation at each unburned site. Welch 2002 Wildfire + / - Nationwide Varied N/A Status Assessment Fire can be beneficial, Pruitt 2000
but altered fire regimes and suppression degrade habitat. Fire may be an acceptable management practice, but must for medium and tall grasses and shrubs. Wildfire + / - Southcentral WA Shrubsteppe Density, nesting success and habitat relationships 154-km vehicular transect, variable width line transects, nest searches Optimal shrike habitat consisted of late seral or climax stands of big sagebrush or bitterbrush that had been partially burned, producing a mosaic of openings and patches of tall, robust shrubs. However, fire is detrimental if it eliminates shrubs. Poole 1992 Fire NC Kansas Tallgrass prairie Unknown Unknown Abundance was not Zimmerman 1993a
significantly different between burned and unburned tallgrass prairie within Grazing + / - Nationwide Varied N/A Status Assessment Grazing practices vary widely by location and manager. Grazing may be an acceptable management practice, but must allow for medium and tall grasses and shrubs for shrikes. Pruitt 2000 Grazing - Unknown Unknown N/A Unknown Trees and shrubs used for nesting and perches should be protected from cattle grazing and rubbing 1996 a Grazing - Southeastern Alberta, Canada Shrub and grassy habitat along railroad embankment Occupied sites Intensive survey in suitable habitat within 100 m of railroad. Did not test grazed vs ungrazed plots, but birds preferred to Prescott and Collister 1993
Located nest considered an “occupied site”. forage in undisturbed areas. Manage for tall grass to improve habitat. Grazing NC Western UT Low-shrub desert Density (pairs/40 ha) Four 9-ha plots censused using Williams spot-map method. Bird only observed in heavy late winter grazing and ungrazed plots; no significant difference in density. 1986 Grazing NC Great Basin (CA/NV) Various habitat types including low sagebrush and big sagebrush Bird abundance One-mile strip census No impact in low sagebrush; inconclusive in big sagebrush habitats Page et al. 1978 Mowing NC Nationwide Varied N/A Status Assessment Mowing can be beneficial, but must allow for medium and tall grasses and shrubs. Pruitt 2000 Mowing NC Florida Cattle Behavior indices Compiled activity budgets pre- and Mowing did not affect hunting success but did alter behavior. Shrikes Yosef and Grubb 1993
overcame tall vegetation to maintain hunting success. P-J expansion NC Northern AZ Grassland Bird species richness Distance sampling Tested bird abundance along ecotone for woodland encroachment Rosenstock and Van Riper III 2001 Juniper removal NC Great Basin, Mono County, CA Pinyon pine woodland with sporadic juniper that merges into sagebrush with decreasing elevation Counts counts and census, nest searching, and territory spot mapping Observed more frequently at untreated plots, but also seen at treated plot. Results inconclusive. Woolley and 2006 Invasive species - Nationwide Varied N/A Status Assessment Invasion of shrub-steppe and habitats by exotics was cited as a threat to Loggerhead Shrikes by species experts in several western states. Pruitt 2000 Invasive species – Cheatgrass - Central WA Sagebrush Steppe interspersed with disturbed and invaded patches Bird Count / frequency of occurrence Walking transects Loggerhead Shrike nest in sagebrush shrubs and Brandt and Rickard 1994
Table 17: Treatment impacts on the Pinyon Jay. "+" = positive response, " - " = negative response, "0" = no effect or results inconclusive, "+ / - " = mixed response. Treatment Response Location Habitat Response Variable Methods Citation Wildfire NC Central OR Semi-arid, upland plant communities Abundance, diversity Sampled and veg communities in 4 cover types: grassland, shrub-steppe; western juniper; old-growth western juniper Pinyon Jays occur primarily in and juniper. No occurrence in post-burn grassland or shrub-steppe lacking juniper. Reinkensmeyer 2000 Prescribed burning - Rocky Mountains Pinyon-juniper woodland N/A Literature Review Treatments, including prescribed fire or other actions that reduce tree density, decrease foraging opportunities Saab et al. 2005 Fire/thinning - Multiple Southwestern conifer forests Counts Literature Review for thinning and burning 6 Pinyon Jay observations and cumulative increase after treatment or high-severity burn/thin Kalies et al. 2010 Grazing NC Northeast NM Eastern slope of Sangre de Cristo Mtns. Low elev = shortgrass prairie, high elev = P-J woodland Counts Random plot selection of grazed and 20-year plots in P-J woodland. Slightly higher detection on ungrazed plots, but difference is not statistically significant Goguen and Mathews 1998 Grazing + Multiple Ponderosa Pine Forest N/A Literature Review This literature review suggests that grazing could open bare ground in ponderosa pine forests, thereby improving forage et al. 1997
opportunities for Pinyon Jays. Pinyon-Juniper removal - Multiple Pinyon-juniper woodland N/A Literature Review Review of management for pinyon-juniper woodlands. Denser woodlands benefit Pinyon Jay. Short and McCulloch 1997 P-J removal - South-Central OR Shrub-steppe Counts Mechanical shearing of juniper; bird census Avian community response to mechanical shearing of juniper in Sabol 2005 Pinyon-juniper removal - Multiple Multiple N/A Review of management in P-J woodlands Summary, no specific treatment actions. Pinyon Jay utilize mature P/J. Retain large trees and limit development at least 1 km from nesting sites. Gillihan 2006 P-J expansion + Northern AZ Grassland Bird abundance/density, species richness Distance sampling Tested bird abundance along ecotone for woodland encroachment Rosenstock and Van Riper III 2001 P-J thinning - Zuni Indian Reservation, western NM and eastern AZ Pinyon-juniper woodland Number of occurrences Fixed point counts Three 1-ha plots thinned at different basal areas. Pinyon Jay occurrence higher at control (unthinned) plots Albert et al. 1995 P-J thinning/removal - Multiple Multiple N/A Literature review Removal of woodlands impacts Pinyon Jays that depend on Zwartjes et al. 2005
mature, cone-bearing pinyons P-J thinning + Manzano Mountains, NM Piñon-Juniper and Ponderosa Pine woodlands Counts counts Standard thinning, reduce basal area by ~50-60%. Results not tested for significance, but increased Pinyon Jay presence on treated (thinned) plots Lightfoot et al. 2016 a
shrubsteppe, coniferous forests when breeding and/or wintering in grasslands. Curlews breeding in shrubsteppe habitats probably respond negatively to grazing. Grazing + / - Multiple Multiple N/A Literature Review Grazing may be beneficial if done at the right time and taking environmental factors into account. Avoid grazing during incubation. Reduction of tall veg is beneficial. Dechant 1999 Grazing + Nebraska Grazed and ungrazed pasture Unknown Unknown Curlews present on grazed areas, and not present in ungrazed pasture. Cole and Sharpe 1976 b Grazing + Comanche National Grassland, CO Grassland Unknown Unknown Long-billed Curlew prefer heavily grazed shortgrass habitats. King 1978 c Dragging + / - Multiple Multiple N/A Literature Review Dragging hayfields can have varying effects. Should be done after breeding season. Dechant 1999 Pesticides 0 Umatilla National Wildlife Refuge, OR Varied, including shrub-steppe of death Investigated organochlorine residues in eggs and tissues of curlews Detrimental effects but extent of impact unclear. Blus et al. 1985 Invasive species – Cheatgrass - South Central WA Sagebrush Steppe interspersed with Bird / frequency of occurrence Walking transects As a ground nester, expected to benefit from reduction of Brandt and Rickard 1994
21: "+" = " - " = "0" = "+ / - " = Treatment Response Location Habitat Response Variable Methods Notes Citation Prescribed burning + Central UT Big sagebrush, cold desert Bird density (territories/16 ha) Bird census with method and flush technique Horned Lark was the only species with higher densities on sites subjected to recent sagebrush control. Densities were 1.8-2.8x greater on recently treated sites. Castrale 1982 Prescribed burning + Snake River plain, ID Big sagebrush Bird density (territories/km2) Territories estimated with spot-map method and census over 5 years Horned colonized burned plots; were not present before burning. Petersen and Best 1987 Prescribed burning + Eastern OR High-elevation mountain big sagebrush Bird abundance 5-minute point-count surveys Greater shrub loss resulted in more Horned Lark. Holmes 2007 Prescribed burning / fire + / NC Multiple Multiple N/A Literature Review Horned Larks densities generally increased or remained unchanged following fire. Knick et al. 2005 Wildfire NC OR, ID, UT, WY, MT Big sagebrush Bird counts Flushing bird counts More Horned Larks on the unburned sites, but difference is too small to make conclusion 2002 Wildfire + Central Columbia Plateau, southeastern WA wheatgrass and Cheatgrass grasslands Abundance (average individuals per count point) counts in six cover types No population trend pre-fire, but increased steadily and significantly after the fire, suggesting a long-lasting positive effect. Earnst et al. 2009
Grazing + Central Plains Experimental Range, northern CO Shortgrass prairie Number observed Plot counts, roadside counts, nest searches, territory determinations, and specimen collections. Found on both and winter pastures grazed at heavy, moderate, and light levels. Showed preference for areas, and use negatively correlates with increasing plant biomass Giezentanner 1970 Grazing + Central Plains Experimental Range, northern CO Shortgrass prairie Relative abundance, distribution, and nesting density Plot census, roadside counts, collections Horned Lark most abundant species on heavily-grazed with short vegetation during the summer. Also recorded on these plots during the winter. More prevalent on heavily grazed plots than lightly grazed plots Giezentanner and 1969 Grazing + North Dakota Idle hayland, mixed- grass/tame pasture, wet- meadow pasture Density Unknown Density higher on twice-over rotation grazing system than short-duration grazing, season-long, or idle. 4 years no differences. Messmer Grazing + South-central ND Mixed-grass prairie Density Census using a single 400-m variable strip transect in each plot Highest density on transects with lowest height-densities of vegetation (heavily grazed). Grazing to favor Horned Larks Arnold and Higgins 1986 expansion - Northern AZ Grassland Bird abundance/density, species richness Distance sampling Tested bird abundance along ecotone for woodland encroachment Rosenstock and Van Riper III 2001
Juniper removal NC Counts Mechanical shearing of juniper; bird census Avian community response to mechanical shearing of juniper in Results inconclusive for Horned Lark Sabol 2005 Juniper removal + Northern AZ Grassland sites along a gradient. Density (birds/ha) Distance sampling. point counts every 250 m along a 1-km transect. Removal or reduction of juniper improves breeding habitat for Horned Rosenstock and Van Riper III 2001 Invasive species – Cheatgrass NC South Central WA Sagebrush Steppe interspersed with disturbed and invaded patches Bird Count / frequency of occurrence Walking transects More common in hopsage / Sandberg’s bluegrass, but did not show preference for cheatgrass sites, though they did nest there. Brandt and Rickard 1994 Invasive species – crested wheatgrass + Central NV Sagebrush control sites and crested wheatgrass treatment sites Relative bird abundance Two parallel transects with 5 circular plots at each site Shrub cover most powerful variable for Horned Lark. Negative affinity suggests shrub avoidance and preference for openness. McAdoo et al. 1989 Invasive species – crested wheatgrass + Eastern ID Big sagebrush and former sagebrush range reseeded with crested wheatgrass Successful nests Visual observation in 4-ha grid. Increased nesting on seeded plots, almost no nesting in native sagebrush plots. Reynolds and Trost 1980 Herbicide + Southern OR rangeland Density (individuals/km2) Recorded all and sound observations along 610 m linear strip transects. Herbicide 2,4-D treatments. Horned Larks negatively related to forb cover and maximum vegetation height. Density increased substantially Wiens and Rotenberry 1985 steppe.
after treatment, but not in year immediately following treatment. Herbicide + Wyoming Shrubsteppe Counts Unknown Numbers of Horned Larks were significantly higher in areas treated with 20-22 years prior to the study. Kerley and Anderson 1995a Pesticide - / NC Pawnee National Grassland, northern CO Shortgrass prairie/rangeland Count (mean count/site) counted on strip transects. Population significantly reduced through emigration, nesting failure, and poisoning mortality on toxaphene plot, but unchanged on malathion and untreated plots. McEwen and Ells 1975 Pesticide - / NC MT, UT, NM Shortgrass prairie Counts Pre- and post-spray census using straightline transect BAY 77488, fenitrothion, and diazinon all caused significant mortality. Mobam and Baygon did not cause significant population declines. McEwen et al. 1972 Pesticide NC CO, ID, ND, UT, WY Multiple Density Line transects and point counts Horned Lark densities not influenced by use of malathion, carbaryl in oil, and carbaryl bait for grasshopper control George et al. 1995 Mine reclamation - South Central WY steppe with saltbrush and greasewood interspersed. Bird Density (birds/ha/census day) 73 censuses with transects through native and reclaimed habitats Reclaimed sites dominated by common halogeton (Halogeton glomeratus). Horned Lark densities Krementz and Sauer 1982