Avian Monitoring in the Lassen National Forest 2009 Report

April 2010 Ryan D. Burnett, Diana Humple, Alissa Fogg, and Tim Guida

PRBO Conservation Science Sierra Nevada Program PO BOX 634 Chester, CA 96020 PRBO Contribution #1740

Executive Summary ...... 1 Chapter 1. Landbird Monitoring of Fuel Treatments on the Lassen National Forest ...... 2 Background and Introduction ...... 3 Methods ...... 4 Results ...... 12 Discussion...... 18 Acknowledgements ...... 20 Literature Cited ...... 21 Chapter 2. Resident and Neotropical Migratory Bird Response to Aspen Enhancement on the Lassen National Forest ...... 24 Background and Introduction ...... 25 Project Area ...... 25 Methods ...... 26 Results ...... 31 Discussion...... 41 Conclusions ...... 45 Acknowledgements ...... 45 Literature Cited ...... 46 Chapter 3. Resident and Neotropical Migratory Bird Monitoring in Mountain Meadows: 2009 Report ...... 48 Background and Introduction ...... 49 Methods ...... 50 Results ...... 54 Discussion...... 62 Conclusions ...... 65 Acknowledgements ...... 65 Literature Cited ...... 66

Executive Summary PRBO Conservation Science (PRBO) has been conducting songbird monitoring in the Northern Sierra since 1997. In this report we present results from avian monitoring of fuel treatments and aspen restoration on the Lassen National Forest and from meadows across the Northern Sierra with updated information from 2009. Chapter one reports on the first year of our expanded avian monitoring of Herger Feinstein Quincy Library Group Forest Recovery Act fuel treatments on the Lassen National Forest. Recently treated sites across the forest were added in 2009 to compliment ongoing work on the Forest as well as in the Plumas-Lassen study area. Preliminary results suggest the range of treatments (DFPZ, Group Selection, mastication, fire) have varying effects on the avian community. The second chapter discusses results from our sixth year of monitoring landbirds in aspen habitat on the Lassen National Forest. Results show that treated aspen stands support greater total abundance of birds and abundance of key species such as Mountain Bluebird, Chipping Sparrow, and Red-breasted Sapsucker but these initial benefits may be short-lived for some species. In 2009, avian abundance and richness indices showed a decline at treated sites for the second consecutive year. In the third chapter we present results from monitoring of meadows across the Northern Sierra Nevada, primarily within the Feather River watershed. We compared avian community indices across sites and where applicable compared treated areas to adjacent reference sites. Results suggest some Feather River watershed meadows still support diverse and abundant bird populations including several species of conservation concern. However, a number of sites have suppressed avian communities - likely a result of over a century of inappropriate management. Management actions that restore hydrologic and ecological function and minimize the negative impacts created through past management actions will likely benefit a number of avian species including several that are of conservation concern.

Chapter 1. Landbird Monitoring of Fuel Treatments on the Lassen National Forest

Diana Humple, Tim Guida, and Ryan D. Burnett PRBO Conservation Science

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Background and Introduction The Records of Decisions for the Sierra Nevada Forest Plan Amendment and Herger Feinstein Quincy Library Group (HFQLG) Forest Recovery Act direct the Forest Service to maintain and restore old forest conditions that provide habitat for a number of plant and animal species (HFQLG 1999, SNFPA 2001, 2004). Simultaneously, they direct the Forest Service to take steps to reduce risks of large and severe fire by removing vegetation and reducing fuel loads in overstocked forests. Striking a balanced approach to achieving these potentially competing goals is a significant challenge to effectively accomplish the various desired outcomes of forest management. Historically, fire was the primary force responsible for creating and maintaining habitat diversity and landscape heterogeneity in the Sierra Nevada (Skinner and Chang 1996). Over the past century, fire return intervals have been lengthened and the area affected by wildfire annually has been dramatically reduced in the interior mountains of California (Taylor 2000, Taylor and Skinner 2003, Stephens et al. 2007). Thus, there is little doubt fires role in influencing the composition of the Sierra Nevada landscape has been reduced (Skinner and Chang 1996). Fire suppression in concert with past silvicultural practices has resulted in increased stand densities, loss of landscape heterogeneity, and increased fuel loads in Sierra Nevada Forests (Vankat and Major 1978, Parsons and DeBenedetti 1979, McKelvey and Johnston 1992, Minnich et al. 1995, Taylor and Skinner 2003). While the ways in which these changes affect fire patterns and vegetation dynamics are frequently discussed, they also undoubtedly impact the wildlife species that inhabit these forests. Mechanical silvicultural treatments have the potential to fill some of fire’s historic role in maintaining disturbance-dependent habitats (Weatherspoon 1996, Arno and Fiedler 2005). There has been considerable study of silvicultural treatments and their effects on landbirds in eastern North American forests (Anand and Thompson 1997, King et al. 2001, Fink et al. 2006, Askins et al. 2007) and the Cascades (Hansen et al. 1995, Hagar et al. 2004, Chambers et al. 2007), but little published information exists on the effects of mechanical fuel treatments on the avian community in the Sierra Nevada (but see Siegel and DeSante 2003 and Garrison et al. 2005). By monitoring the populations of a suite of landbird species we can measure the effectiveness of management actions in achieving a sustainable and ecologically functional forest

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

ecosystem. Specifically, we are interested in determining the responses of landbirds to management practices intended to produce forests with larger trees and high canopy cover along with more open-canopy, smaller size class forest with reduced ladder and ground fuels. In this report we summarize our efforts in 2009 intended to investigate landbird response to changes in vegetation structure and composition that occur when forests are managed to reduce fuels under the Herger Feinstein Quincy Library Group Forest Recovery Act Pilot Project (HFQLG 1999). We summarize what surveys were completed in 2009, the treatment history at each site, and some preliminary analysis of bird community indices by treatment type. We compared community indices and most abundant species among treatment types and between paired treated and reference sites. Future analyses will be more comprehensive, combining data with those from the larger HFQLG region in which PRBO is collecting bird data (e.g., Plumas National Forest). Future analysis will also include analysis of the longer-term effects of fuel treatments on the avian community.

Methods

Study Location The study occurred in the Lassen National Forest within the boundaries of the HFQLG Forest Recovery Act Pilot Project with the exception of the Wiley Ranch sites. The study sites encompassed portions of Butte, Lassen, Plumas, Shasta and Siskiyou (Wiley Ranch) Counties at the intersection of the Sierra Nevada and Cascade mountains of Northeastern California, USA (Figure 1). Survey sites ranged in elevation from 1362 to 2074m with a mean elevation 1628m. All sites occurred within the mixed conifer, true fir, and yellow pine zones though the actual habitat structure and dominant tree species varied by site. A total of 519 point count stations across 49 transects was surveyed in 2009 (Figure 1 and Table 1).

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Figure 1. Location of of PRBO’s fuel treatment avian monitoring study sites in the Lassen National Forest. Black dots are point count stations and the Lassen National Forest is the area in green. Note, Brown’s Ravine study area includes Lower, Middle and Upper Oak Reference transects. Wiley Ranch is located approximately 20km north of the map on the Shasta Trinity National Forest but is administered by the Lassen National Forest.

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Table 1. Fuel treatment point count transects, Lassen National Forest 2009. Summary of transect, number of points per transect, treatment type and details, if treatment has occurred, and year of treatment. Transect Code # Points Ranger District Treatment Type Treated Year Treated Battle BATL 13 Almanor DFPZ yes 2004 Bizz DFPZ BIZD 7 Eagle Lake DFPZ yes 2005 Bizz Reference BIZR 7 Eagle Lake Reference n/a Black's Ridge DFPZ BRDZ 12 Hat Creek DFPZ yes 2004 Black's Ridge Group Selection BRGS 12 Hat Creek Group Selection yes 2008 Cabin Mastication CBMA 11 Hat Creek Plantation/Mastication yes 2006 Carter Meadow Road CMRO 12 Almanor Wildfire n/a (2008) Gray's Peak Central GPCE 10 Almanor Plantation/Mastication no Gray's Peak East GPEA 14 Almanor Plantation/Mastication no Gray's Peak West GPWE 13 Almanor Plantation/Mastication no Hog DFPZ HOGD 7 Eagle Lake DFPZ yes 2004 Hog Reference HOGR 7 Eagle Lake Reference n/a Harvey Valley DFPZ HVD 7 Eagle Lake DFPZ no Harvey Valley Reference HVR 7 Eagle Lake Reference n/a Jonesville DFPZ JVDZ 12 Almanor DFPZ yes 2005/2006/2007 Konos DFPZ KOND 7 Eagle Lake DFPZ yes 2007 Konos Reference KONR 7 Eagle Lake Reference n/a Lower Oak Reference LOKR 32 Almanor Reference n/a Middle Oak Reference MOKR 6 Almanor Reference n/a North Cobble DFPZ NCDZ 12 Hat Creek DFPZ/Group Selection yes 2006 North Cobble Mastication NCMA 12 Hat Creek Plantation/Mastication yes 2007 Brown’s Ravine Oak Stand 1 OAK1 7 Almanor DFPZ yes 2005 Brown’s Ravine Oak Stand 2 OAK2 14 Almanor DFPZ yes 2005 Brown’s Ravine Oak Stand 3 OAK3 10 Almanor DFPZ yes 2005 Brown’s Ravine Oak Stand 4 OAK4 14 Almanor DFPZ yes 2006/2007 Brown’s Ravine Oak Stand 5 OAK5 7 Almanor DFPZ yes 2006/2007 Brown’s Ravine Oak Stand 6 OAK6 6 Almanor DFPZ no Brown’s Ravine Oak Stand 7 OAK7 8 Almanor DFPZ no Brown’s Ravine Oak Stand 8 OAK8 7 Almanor DFPZ no Brown’s Ravine Oak Stand 9 OAK9 6 Almanor DFPZ yes 2006/2007 Peg DFPZ PEGD 7 Eagle Lake DFPZ no

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Transect Code # Points Ranger District Treatment Type Treated Year Treated Peg Reference PEGR 7 Eagle Lake Reference n/a Pittville North DFPZ PNDZ 12 Hat Creek Group Selection/Prescribed Fire yes 2005/2008 Pittville South DFPZ PSDZ 12 Hat Creek DFPZ/Group Selection yes 2005 Round DFPZ RNDD 8 Eagle Lake DFPZ yes 2005 Round Reference RNDR 7 Eagle Lake Reference n/a Storrie Fire Mastication East STME 10 Almanor Plantation/Mastication no fall 2009 Storrie Fire Mastication West STMW 11 Almanor Plantation/Mastication no Stover STVR 12 Almanor Plantation/Mastication yes 2007 Upper Oak Reference UOKR 36 Almanor Reference n/a Warner Burn WABU 12 Almanor Prescribed Fire yes 2006 Warner DFPZ WADZ 12 Almanor DFPZ yes 2006/2007 Wiley Ranch North WRNO 16 Hat Creek DFPZ no Wiley Ranch South WRSO 16 Hat Creek DFPZ no West Shore North DFPZ WSND 8 Almanor DFPZ yes 2002/2004 West Shore North Reference WSNR 6 Almanor Reference n/a West Shore South DFPZ WSSD 9 Almanor DFPZ yes 2002/2004 West Shore South Reference WSSR 4 Almanor Reference n/a Young Pine YOPI 8 Almanor Plantation/Mastication no TOTAL 519

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Site Selection and Treatment History We combined data across multiple projects on the Almanor, Eagle Lake, and Hat Creek Ranger Districts of the Lassen National Forest (Table 1) to investigate the effects of HFQLG treatments on landbirds. Treatments included Defensible Fuel Profile Zones (DFPZ), Group Selection, Plantation/Mastication, and fire (prescribed and wild) (Table 2). Treatments, and specific treatment histories at given transects and point count stations, are summarized in Table 1.

Table 2. Forest treatment types in the Northern Sierra Nevada for which the response of landbirds was investigated in 2009. Treatment Description Defensible Fuel Profile Zones Mechanically created shaded fuel break, generally linear in shape; (DFPZ) affects more acres than any treatments in our study area. Group Selection Removal of all overstory trees in 0.5 – 2 acre area, sometimes embedded within a DFPZ network. Plantation/Mastication Plantings of Ponderosa Pine. Mechanical shredding of shrubs that sometimes uproots shrubs but often leaves plants alive below ground to regenerate. Burn Generally low intensity human ignited burning. Generally consumes understory fuels and some middle story trees. Some sites experienced wildfire or backfires set during a wildfire.

DFPZ treatments monitored on the Eagle Lake Ranger District were established in 2004 after consulting ranger district staff and available GIS layers. We selected 6 sites that were slated for treatment in the next several years. At each treatment area we established between 5 to 7 point counts inside of treatment boundaries and 5 to 8 sites in similar habitat at least 100m outside the treatment but within 500m of the treated area (see Burnett et al. 2004). A similar protocol was used for the Brown’s Ravine Black Oak enhancement DFPZ project in the Almanor Ranger District of the Lassen (Table 1). In this project, treatment units were larger so we filled each unit with points spaced 220m apart. Each unit contained between 5 and 14 points. Reference sites were established in adjacent units where no treatment was planned (Burnett et al. 2004). In 2009, 21 new transects comprising 261 point-count stations were added to the project (Table 1) in the Almanor and Hat Creek Ranger Districts. We had already established six transects in DFPZ’s on the Eagle Lake rangers district in 2004, of which five had already been treated so we did not add additional sites in that district in 2009. We used GIS layers of the boundaries of fuel projects that had already been implemented 8

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

to select new monitoring sites in the Almanor and Hat Creek ranger districts. We chose projects that had been completed in the past five years and were large enough to contain a minimum of 8 point count stations spaced 250m apart. We also selected projects in order to obtain a sample of each of the four treatment types described in Table 2 above. In addition to the previously treated fuel treatment sites, we also established transects within the proposed Gray’s Peak project area and Storrie Fire mastication units on the ARD. We used a similar site selection protocol as described above where GIS layers of unit boundaries were employed to establish points in a way that would maximize the points a person could sample in one morning while covering the majority of treatment units in the project. Additionally three plantation study sites where we had already established monitoring in previous years – Young Pine II, Carter Meadow Road, and Stover (Young Pine I) – are included in this analysis and there site selection was very similar to that already described above. For all of these sites we had no prior knowledge of the site conditions prior to establishing the points. With the exception of the West Shore North and South DFPZ’s, we did not establish adjacent reference points for any of these new transects. For each point count station, we identified the treatment history with respect to four distinct treatment types (Tables 1 & 2). A given treatment was only considered to occur at a point if the point fell inside the treatment polygon. Of the 519 points, 277 had been treated in one or more ways prior to the 2009 point count seasons; the remaining points were considered a combination of sites that have not yet been treated (but will be) or were reference sites paired with treated units (Table 3).

Table 3. The number of point count stations by treatment type in each ranger district in PRBO’s Northern Sierra study area in 2009. Each point was visited twice in 2009. Eagle Hat Treatment Type Almanor Lake Creek Total Number of points 319 85 115 DFPZ Number of points 133 43 58 Number of post-treatment points 108 29 26 Group Selection Number of points 0 0 27 Number of post-treatment point visits n/a n/a 27 Mastication Number of points 78 0 23 1 Number of post-treatment point visits 12 n/a 23 Burn Number of points 24 0 7 2 Number of post-treatment point visits 24 n/a 7 Reference Number of reference points 84 42 0 121 points were treated fall 2009 (after point count surveys complete, 212 prescribed burn, 12 wildfire (backfire) 9

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Survey Protocol We used a standardized five-minute variable circular plot point count census (Reynolds 1980, Ralph et al. 1993, Ralph et al. 1995) to sample the avian community in the study area. In this method, points are clustered in transects, but data were only collected from fixed stations, not along the entire transect. In 2009, all birds detected at each station during the five-minute survey were recorded according to their initial distance from the observer. Detections were recorded to the nearest meter up to 300 meters. Beyond 300 meters observations were recorded simply as greater than 300 meters. The method of initial detection (song, visual, or call) for each individual was also recorded. All observers underwent intensive 14 day training in bird identification and distance estimation prior to conducting surveys. Laser rangefinders were used to assist in distance estimation at every survey point. Counts began around local sunrise, were completed within four hours, and did not occur in inclement weather. Each transect was visited twice during the peak of the breeding season from mid-May through the first week of July (Table 4).

Table 4. Dates of point count visits, Lassen National Forest fuel treatment transects 2009. code visit 1 visit2 BATL 6/1/2009 6/20/2009 BIZD 5/14/2009 6/21/2009 BIZR 5/14/2009 6/21/2009 BRDZ 6/9/2009 6/18/2009 BRGS 6/9/2009 6/18/2009 CBMA 6/12/2009 6/29/2009 CMRO 6/2/2009 6/24/2009 GPCE 5/30/2009 6/15/2009 GPEA 6/1/2009 6/15/2009 GPWE 5/30/2009 6/15/2009 HOGD 5/15/2009 6/21/2009 HOGR 5/15/2009 6/21/2009 HVD 5/25/2009 6/23/2009 HVR 5/25/2009 6/23/2009 JVDZ 6/1/2009 6/14/2009 KOND 5/16/2009 6/30/2009 KONR 5/16/2009 6/30/2009 LOKR 5/18/2009, 5/19/2009 6/16/2009, 6/17/2009, 6/18/2009 MOKR 5/23/2009 6/25/2009 NCDZ 6/3/2009 6/19/2009 NCMA 6/3/2009 6/19/2009 OAK1 5/18/2009, 5/19/2009 6/16/2009, 6/17/2009

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009 code visit 1 visit2 OAK2 5/18/2009, 5/19/2009 6/16/2009, 6/17/2009 OAK3 5/18/2009 6/16/2009 OAK4 5/23/2009 6/25/2009 OAK5 5/23/2009 6/25/2009 OAK6 5/21/2009 6/26/2009 OAK7 5/21/2009, 5/22/2009 6/23/2009, 6/25/2009, 6/26/2009 OAK8 5/21/2009, 5/22/2009 6/23/2009, 6/25/2009 OAK9 5/19/2009 6/17/2009 PEGD 5/16/2009 6/11/2009 PEGR 5/16/2009 6/11/2009 PNDZ 6/10/2009 6/18/2009 PSDZ 6/3/2009 6/19/2009 RNDD 5/16/2009 6/11/2009 RNDR 5/16/2009 6/11/2009 STME 5/24/2009 6/20/2009 STMW 6/11/2009 6/30/2009 STVR 5/29/2009 6/24/2009 UOKR 5/21/2009, 5/22/2009 6/23/2009, 6/25/2009, 6/26/2009 WABU 6/2/2009 6/27/2009 WADZ 6/2/2009 6/27/2009 WRNO 6/12/2009 6/20/2009 WRSO 6/12/2009 6/20/2009 WSND 6/8/2009 6/29/2009 WSNR 6/8/2009 6/29/2009 WSSD 6/8/2009 6/24/2009 WSSR 6/8/2009 6/24/2009 YOPI 6/8/2009 6/24/2009

Statistical Analysis Annual per-point species abundance, richness, and diversity metrics of birds within 50 meters were summarized for 519 points. We excluded species that are not adequately sampled using the point count method (e.g., waterfowl, shorebirds, kingfisher, and raptors), as well as species not breeding in the region (e.g., Rufous Hummingbird). We also excluded European Starling and Brown-headed Cowbird from analysis of species richness and total bird abundance because they are invasive species regarded as having a negative influence on the native bird community. Birds unidentified to species (e.g., XXWA, Unidentified Warbler) were included in abundance estimates and, if the only one of that taxa, in richness estimates, but were excluded from diversity indices. We define species richness as the mean number of species detected within 50 meters of the observer per point across visits. The index of total bird abundance is the

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

mean number of individuals detected per point per visit; this number is obtained by dividing the total number of detections within 50 meters by the number of stations and the number of visits (2). Species diversity was measured using a modification of the Shannon-Wiener index (Krebs 1989) introduced by MacArthur (1965), which reflects combined species richness and equal distribution of the species. Diversity can be considered as mean species diversity (average diversity per point). The relative abundance of species is the mean number of detections of a given species per point per visit within 50 meters of observers. We determined community indices for each transect. We also compared community indices (richness and abundance), as well as the abundance within 50 meters of the ten most common species (at all study sites combined), among treatment types. Means and confidence intervals were generated with StataIC 10.0 (StataCorp 2007). For this, we lumped untreated sites with reference sites as “Untreated/Reference”. We assigned points where group selection had occurred inside of another treatment simply as group selection; we lumped prescribed burn and wildfire burned points under the “treatment” category of “Fire”. The ten most abundant species were, in order: Mountain Chickadee, Audubon’s Warbler, Dusky Flycatcher, Oregon Junco, Red-breasted Nuthatch, Golden-crowned Kinglet, Hermit Warbler, Chipping Sparrow, Western Tanager, and Fox Sparrow. Additionally, we compared these indices for paired reference versus treated transects using a two-tailed t-test, and included only sites that had been treated prior to the 2009 breeding season; these included Biz, Hog, Konos, Round, West Shore North, and West Shore South (DFPZ and Reference transects, respectively).

Results Community Indices by Transect Ninety-six species in total were detected across the 49 transects in 2009. Seventy- nine were used in assessing community indices (17 species were removed because they were not appropriate to assess via the point count method; see Methods above). Community index values were highly variable among transects (Table 5). Diversity values were as low as 0.99 (Wiley Ranch South, untreated DFPZ), with the most diverse sites having diversity values as high as 7.53 (Carter Meadow Road, hand

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

conifer release in 2001 and burned in 2008 Cub fire), 7.63 (Battle, 5 years post DFPZ treatment), and 8.70 (West Shore South Reference). Abundance values ranged from 0.59 birds per point (Wiley Ranch South) to 7.04 (Battle), 7.06 (West Shore South DFPZ, treated in 2002 or 2004), and 7.25 (West Shore South Reference) birds per point. Species richness values ranged from 1.00 (Wiley Ranch South) up to 8.54 (Battle), 8.58 (Carter Meadow Road), and 9.5 (West Shore South Reference).

Table 5. Point count indices for fuel treatment transects, Lassen National Forest 2009. Diversity Abundance Species Station (sw) (individuals/visit) richness BATL 7.63 7.04 8.54 BIZD 3.78 2.71 4.00 BIZR 5.40 4.71 6.00 BRDZ 6.70 6.67 7.58 BRGS 3.08 2.00 3.17 CBMA 6.20 6.14 7.00 CMRO 7.53 6.71 8.58 GPCE 5.26 4.35 5.70 GPEA 4.91 4.82 5.57 GPWE 6.85 5.96 7.54 HOGD 3.36 2.57 3.71 HOGR 3.48 2.86 3.71 HVD 4.24 3.21 4.71 HVR 3.79 2.71 4.00 JVDZ 4.96 3.67 5.33 KOND 4.12 3.21 4.43 KONR 5.22 4.07 5.57 LOKR 5.88 4.80 6.38 MOKR 6.41 4.75 6.83 NCDZ 5.04 3.79 5.42 NCMA 3.42 3.17 3.83 OAK1 6.04 4.43 6.57 OAK2 6.75 5.36 7.29 OAK3 6.46 5.35 7.20 OAK4 5.86 4.25 6.29 OAK5 4.62 4.07 4.86 OAK6 5.84 4.17 6.17 OAK7 4.88 3.69 5.25 OAK8 4.97 3.93 5.29 OAK9 4.84 3.00 5.00 PEGD 3.94 3.57 4.43 PEGR 5.31 4.14 5.86 PNDZ 5.74 4.29 6.25 PSDZ 5.33 4.00 5.75 RNDD 2.48 2.00 2.63

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Diversity Abundance Species Station (sw) (individuals/visit) richness RNDR 4.17 3.07 4.43 STME 6.15 5.75 6.80 STMW 5.24 4.05 5.55 STVR 3.86 3.25 4.17 UOKR 6.20 4.93 6.75 WABU 7.31 4.88 7.67 WADZ 6.58 5.21 7.17 WRNO 2.88 1.88 3.00 WRSO 0.99 0.59 1.00 WSND 6.01 5.06 6.75 WSNR 5.16 3.83 5.50 WSSD 7.18 7.06 8.11 WSSR 8.70 7.25 9.50 YOPI 5.18 4.44 5.75

Community Indices between Treated and Untreated Paired Transects Comparing indices of abundance and richness between paired transects, a general pattern was observed of higher community indices at the reference sites than at the treated DFPZ sites (Figures 2 and 3; Table 5). The mean total bird abundance per point was significantly higher in the reference transect than the treated transect for BIZ (2.71 versus 4.71 birds/pt; t-statistic = -2.77, P = 0.02). The mean richness per point was significantly higher in the reference transect than the treated transect for RND (2.63 versus 4.43 species/pt; t-statistic = -2.31, P = 0.04). Differences also approached significant between treated and reference sites for Bizz, Konos and West Shore South species richness and for Round total abundance; for all, they were again greater in the reference site.

Table 5. Comparison between paired treated DFPZ versus reference transects, Lassen National Forest 2009. Index of Abundance Species Richness DFPZ Ref Test P DFPZ Ref Test Mean (SE) Mean (SE) statistic Value Mean (SE) Mean (SE) statistic P Value BIZ 2.71 (0.56) 4.71 (0.45) -2.77 0.02* 4.00 (0.87) 6.00 (0.58) -1.91 0.08 HOG 2.57 (0.52) 2.86 (0.5) -0.40 0.70 3.71 (0.36) 3.71 (0.68) 0 1.00 KON 3.21 (0.55) 4.07 (0.32) -1.34 0.20 4.43 (0.48) 5.57 (0.48) -1.68 0.12 RND 2.00 (0.37) 3.07 (0.48) -1.70 0.11 2.63 (0.33) 4.43 (0.72) -2.31 0.04* WSN 5.06 (0.67) 3.83 (0.75) 1.22 0.25 6.75 (0.75) 5.50 (1.18) 0.94 0.37 WSS 7.06 (0.44) 7.25 (0.72) -0.24 0.82 8.11 (0.39) 9.50 (0.65) -1.92 0.08 *significant at the P < 0.05 level

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

In a few cases (e.g., Hog richness and abundance and West Shore South abundance), indices were similar between paired treated and reference transects. Although the opposite pattern was observed for West Shore North, the results are not significant as the confidence intervals overlap.

Figure 2. Index of abundance from paired DFPZ versus reference point count stations, Lassen National Forest 2009. Error bars represent 95% confidence intervals.

Total Abundance (DFPZ vs. Reference) 12

8 (<50m)

6 DFPZ visit Ref per 4 birds

# 2

Mean 0 BIZ HOG KON RND WSN WSS

Community Indices and Species Abundance Among Treatment Types

Figures 3, 4 and 5 summarize community indices among treatment types. The treatment type with the highest indices overall, and higher than any of the other treatment types (P<0.05), was burn. DFPZ treatment points overall had the second highest indices; diversity and richness there were higher (P<0.05) than any other treatment type except burn. Group selection treatment sites had the lowest community indices.

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Figure 3. Mean per point richness values for paired DFPZ versus reference point count stations, Lassen National Forest 2009. Error bars represent 95% confidence intervals.

Species Richness (DFPZ vs. Reference) 14

(<50m) 10

point 8 DFPZ per

6 Ref

species 4

# 2

Mean 0 BIZ HOG KON RND WSN WSS

Figure 3. Species diversity (mean diversity per point per visit within 50m) for Lassen National Forest fuel treatment point counts 2009. Error bars represent 95% confidence intervals.

Shannon Index of Diversity 9.00 8.00 7.00 point 6.00 per

5.00 4.00 3.00 Burn 2.00 DFPZ diversity 1.00 0.00 Group Selection bird Plantation/Mastication Untreated/Reference Burn DFPZ Mean Selection

Group Untreated/Reference Plantation/Mastication

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Figure 4. Bird abundance (mean number of individual birds per point per visit within 50m) for Lassen National Forest fuel treatment point counts 2009. Error bars represent 95% confidence interval.

Total Bird Abundance 7.00 6.00 50m) 5.00 (< 4.00 3.00 point Burn 2.00 per

DFPZ 1.00 0.00 Group Selection birds Plantation/Mastication Untreated/Reference Burn DFPZ Mean Selection

Group Untreated/Reference Plantation/Mastication

Figure 5. Species richness (mean number of species per point per visit within 50m) for Lassen National Forest fuel treatment point counts 2009. Error bars represent 95% confidence interval.

Species Richness 10.00 9.00 8.00 point 7.00 6.00 per 5.00 4.00 3.00 Burn species 2.00 DFPZ

of 1.00 0.00 Group Selection Plantation/Mastication Burn

DFPZ Untreated/Reference number

Selection

Mean Group Untreated/Reference Plantation/Mastication

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Bird species more associated with trees and canopy (e.g., Mountain Chickadee, Hermit Warbler, and Western Tanager), as well as those associated with open understory (Oregon Junco) were most common at the treated DFPZ points. Species associated with a shrub understory were most common in the burn treatment category.

Table 6. Mean species abundance (and standard error) for top 10 most abundant species (detections <50m from observer) over the project area, by treatment type, Lassen National Forest 2009. Highest value of a given index across all treatment levels is shown in bold. Species are listed in taxonomic order. Group Plantation/ Untreated/ Burn DFPZ Selection Mastication Reference n=31 n=184 n=27 n=35 n=242 Dusky Flycatcher 0.62 (0.12) 0.35 (0.04) 0.04 (0.03) 0.47 (0.09) 0.50 (0.04) Mountain Chickadee 0.35 (0.07) 0.58 (0.04) 0.28 (0.06) 0.57 (0.10) 0.38 (0.03) Red-breasted Nuthatch 0.24 (0.06) 0.24 (0.03) 0 (0) 0.17 (0.06) 0.25 (0.03) Golden-crowned Kinglet 0.24 (0.08) 0.19 (0.02) 0 (0) 0.14 (0.05) 0.24 (0.03) Audubon’s Warbler 0.16 (0.04) 0.51 (0.04) 0.20 (0.06) 0.54 (0.11) 0.41 (0.03) Hermit Warbler 0.16 (0.05) 0.27 (0.03) 0 (0) 0.11 (0.07) 0.17 (0.02) Western Tanager 0.19 (0.05) 0.26 (0.03) 0.07 (0.033) 0.17 (0.05) 0.13 (0.02) Chipping Sparrow 0.27 (0.11) 0.23 (0.04) 0.46 (0.09) 0.26 (0.08) 0.11 (0.02) Oregon Junco 0.32 (0.07) 0.48 (0.04) 0.37 (0.07) 0.21 (0.06) 0.31 (0.03) Fox Sparrow 0.45 (0.14) 0.02 (0.01) 0.02 (0.02) 0.13 (0.07) 0.25 (0.03)

Discussion In 2009, PRBO monitored 49 point count transects totaling 519 points as part of our long-term landbird response to fuel treatments project. Such long-term monitoring is allowing us to assess how fuel reduction treatments change the composition and abundance of landbird species over space and time. Along with our Plumas-Lassen study these two data sets provide us with the most comprehensive study of the response of landbirds to fuel treatments anywhere in the Sierra Nevada. Overall, we found that bird community indices were highest at burned sites, consistent with findings from our Plumas-Lassen study (Burnett et al. 2009). Sites selected for prescribed fire may be in areas with lower fuel loads which allow for the use of prescribed fire. The other treatment type with relatively high indices overall were DFPZ’s. As with fire, it will be important to tease out the effect of time since treatment in order to truly understand the impacts of DFPZ management practices on landbirds but our preliminary data and that from the Plumas-Lassen study suggest that the effects of DFPZ treatments on landbirds are mixed both in terms of species response and site to site 18

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

differences. The pre-existing conditions at a site and the prescription of the DFPZ treatment are both factors that likely contribute to the response of the avian community to treatments. We continue to suggest that treatments that retain variable canopy cover and target areas of lower overall avian diversity (e.g. overly dense 2nd growth white fir forest) will likely have the greatest positive impact on the landbird community. The treatment type with the lowest community indices overall was Group Selection – a treatment that removes all of the overstory of trees in a 1- 2 acre area. However, the fact that all Group Selection transects were in the Hat Creek Ranger District may be biasing this result and as with DFPZ’s, the effects of group selections on the avian community is likely heavily contingent on the pre-existing condition at the site and landscape context of the treatment. For example, we did not find a significant effect of group selections on avian diversity in denser west side forest on Plumas National Forest (Burnett et al. 2009). This may be because our group selection sites often straddled the edges of treatments since they were established prior to treatments and boundaries were moved slightly. Whereas in the LNF we established points after treatments had been implemented and thus were able to place our point count stations in the center of the group selections and thus surveyed less edge. We would expect lower bird diversity within group selections immediately following treatments as the vast majority of vegetation structure has been removed however, few negative effects were found in group selection treatments in pine-hardwood dominated stands in the central Sierra Nevada (Garrison et al. 2005). Of the top ten most abundant species, each treatment type could boast having the highest abundance of at least one of the species across all five treatments. The two treatments that had the greatest abundance of the largest number of species were, again, DFPZ and burn. The species most common in burn varied in life history from species associated with understory shrub habitat (Dusky Flycatcher, Fox Sparrow) to a species associated with large trees (Golden-crowned Kinglet), reflecting the diversity in habitats created after fires, especially when combining sites that burned in different years and different intensities. The species most common in DFPZ were generalists (Mountain Chickadee and Oregon Junco) or mature forest associated species (Hermit Warbler and Western Tanager).

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

When we compared indices of abundance and richness between paired transects, a general pattern was observed of significantly higher community indices at the reference sites than at the treated DFPZ sites. Because this result differs from the higher indices observed across all five treatment types at DFPZ than reference sites, when not restricted to the paired sites, this underscores the usefulness of conducting studies with paired sites when possible. This also suggests there maybe some at least short-term loss in habitat quality for the landbird community at sites that have been converted to shaded fuel breaks. In the northern Sierra Nevada, many species are associated with foliage volume in the middle and especially understory (Verner and Larson 1989). It is this component (fuel ladders) of the habitat that is often removed during DFPZ treatments (as well as in group selection, pre-commercial thinning, and mastication) and could result in short-term declines of a number of species following fuel reduction treatments. However, in group selections and mastication understory, foliage volume is likely to return whereas in shaded fuel breaks (>40% canopy cover retained) it may be less likely to return. It is for these reasons that we suggest a mosaic design of varying canopy covers in fuel treatments be prescribed. Consistent with previous results, our preliminary data from the LNF fuel treatments suggest that sites treated with low to moderate intensity fire – including prescribed fire – harbor some of the highest landbird diversity in the Northern Sierra Nevada. The use of low to moderate intensity fire should be greatly increased in these forests. We focused in this report on summarizing 2009 efforts and results, but intend in the coming years to conduct more comprehensive analyses, both spatially and temporally. We remain conservative about generalizing patterns thus far, as a more in depth analysis will take into account time since treatment, pre versus post treatments, and spatial patterns unrelated to treatment.

Acknowledgements Funding for this project was provided by the Lassen National Forest and Herger Feinstein Quincy Library Group Forest Recovery Act monitoring funds. We especially would like to thank Coye Burnett, Tom Frolli, Karen Harville, Bobette Jones, Tom Rickman, and Mark Williams of the Lassen National Forest and Colin Dillingham – the 20

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

USFS QLG monitoring coordinator - for their support and assistance with this project. We also wish to thank Tim Guida, crew leader, and Nathan Fronk and Luke Owens, our 2009 field crew.

Literature Cited

Anand, E.M. and F.R. Thompson III. 1997. Forest bird response to regeneration practices in central hardwood forests. The Journal of Wildlife Management 61, 159-171. Arno, S.F., and C.E. Fiedler. 2005. Mimicking Nature’s Fire: Restoring Fire Prone Forests in the West. Island Press, Washington D.C.

Askins, R.A., B Zuckerberg, and L. Novak. 2007. Do the size and landscape context of forest openings influence the abundance of breeding success of shrubland songbirds in southern New England? Forest Ecology and Management 250, 137- 147.

Burnett, R.D., D.Humple, T.Gardali, and M.Rogner. 2004. Avian Monitoring in the Lassen National Forest. A PRBO report to the USFS. Contribution # 1242.

Burnett, R.D., N.Nur, and C.A.Howell. In prep. Implications of spotted owl management for landbirds in the Sierra Nevada, CA, USA. Forest Ecology and Management.

Burnett, R.D., D. Jongsomjit, and D. Stralberg. 2009. Avian monitoring in the Plumas and Lassen National Forest: 2008 Annual Report. PRBO report to the U.S. Forest Service. Contribution # 1684.

Chambers, C.L., W.C. McComb, and J.C. Tappeiner II. 1999. Breeding bird responses to three silvicultural treatments in the Oregon Coast Range. Ecological Applications 9: 171-185.

ESRI 2000. Arc View GIS 3.2a. Environmental Systems Research Institute. Redlands, CA.

Fink, A.D., F.R. Thompson III, and A.A. Tudor. 2006. Songbird use of regenerating forest, glade, and edge habitat types. Journal of Wildlife Management 70, 180- 188.

Garrison, B.A., M.L. Triggs, and R.L. Wachs. 2005. Short-term effects of group-selection timber harvest on landbirds in montane hardwood-conifer habitat in the central Sierra Nevada. Journal of Field Ornithology 76: 72-82.

Hagar, J., S. Howlin, and L.Ganio. 2004. Short-term response of songbirds to experimental thinning of young Douglas-fir forests in the Oregon Cascades. Forest Ecology and Management 199: 333-347.

Ch. 1. Fuel Treatments PRBO Avian Monitoring in the Lassen National Forest – 2009

Hansen, A.J., W.C. McComb, R. Vega, M.G. Raphael, and M. Hunter. 1995. Bird habitat relationships in natural and managed forests in the west cascades of Oregon. Ecological Applications 5: 555-569.

HFQLG (Herger-Feinstein Quincy Library Group Forest Recovery Act) 1999. Final Environmental Impact Statement, U.S. Department of Agriculture, Forest Service, Pacific Southwest Region, Vallejo, CA. http://www.fs.fed.us/r5/hfqlg/publications/1999_feis/TOC.htm

King, D.I., R.M. Degraaf, and C.R. Griffin. 2001. Productivity of early successional shrubland birds in clearcuts and groupcuts in an eastern deciduous forest. Journal of Wildlife Management 65: 345-350.

Krebs, C.J. 1989. Ecological Methodology. Harper and Row Publishers, New York, New York: 654 pp.

MacArthur, R.H. 1965. Patterns of species diversity. Biological Reviews 40:510-533.

Martin, T.E. and G.R. Geupel. 1993. Nest monitoring plots: Methods for locating nests and monitoring success. J. Field Ornith. 64:507-519.

McKelvey, K.S. and J.D. Johnston. 1992. Historical perspectives on forests of the Sierra Nevada and the Transever Ranges of Southern California: Forest conditions at the turn of the century. Pp. 225-246 In The California spotted owl: a technical assessment of its current status. Tech Coordination by J. Verner, K.S. McKelvey, B.R. Noon, R.J. Gutierrez, G.I. Gould Jr., and T.W. Beck. Pacific Southwest Research Station General Technical Report 133. Albany, CA.

Minnich, R.A., M.G. Barbour, J.H. Burk, and R.F. Fernau. 1995. Sixty years of change in California coniferous forests of the San Bernardino mountains. Conservation Biology 9:902-914.

Parsons, D.J. and S.H. Benedetti. 1979. Impact of fire suppression on a mixed-conifer forest. Forest Ecology and Management 2: 21-33.

Ralph, C.J., G.R. Geupel, P. Pyle, T.E. Martin, and D.F. DeSante 1993. Field Methods for Monitoring Landbirds. U.S. Department of Agriculture, Forest Service, General Technical Report PSW-144.

Ralph, C.J., S. Droege, and J.R. Sauer. 1995. Managing and monitoring birds using point counts: standards and applications. In C. J. Ralph, J. R. Sauer and S. Droege (eds.), Monitoring Bird Populations by Point Counts. USDA Forest Service Publication, Gen. Tech. Rep. PSW-GTR-149, Albany, CA .

Reynolds, R.T., J.M. Scott, and R.A. Nussbaum. 1980. A variable circular plot method for estimating bird numbers. Condor 82:309:313.

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Siegel, R.B. and D.F. DeSante. 2003. Bird communities in thinned versus unthinned sierran mixed conifer stands. Wilson Bulletin 115: 155-165.

Skinner, C.N. and C.Chang. 1996. Fire regimes, past and present. Sierra Nevada Ecosystem Project: Final Report to Congress. Vol. 2, Assessments and scientific basis for management options, pp. 1041-1069. University of California Centers for Water and Wildland Resources, Davis, CA, USA.

SNFPA 2001. Sierra Nevada Forest Plan Amendment Final Environmental Impact Statement, Record of Decision. United States Department of Agriculture, Forest Service, Pacific Southwest Region, Vallejo, CA. http://www.fs.fed.us/r5/snfpa/library/archives/rod/rod.pdf

SNFPA 2004. Sierra Nevada Forest Plan Amendment, Final Supplemental Environmental Impact Statement, Record of Decision. United States Department of Agriculture, Forest Service, Pacific Southwest Region, Vallejo, CA. http://www.fs.fed.us/r5/snfpa/final-seis/rod/

Stata Corp. 2007. Intercooled Stata 10 for Windows. Stata Corp. LP College Station, TX.

Stephens, R.E. Martin, and N.E. Clinton. 2007. Prehistoric fire area and emissions from California forests, woodlands, shrublands, and grasslands. Forest Ecology and Management 251: 205-216.

Taylor, A.H. 2000. Fire regimes and forest changes along a montane forest gradient, Lassen Volcanic National Park, southern Cascade Mountains, USA. Journal of Biogeography 27:87-104.

Taylor, A.H. & C.N. Skinner. 2003. Spatial patterns and controls on historical fire regimes and forest structure in the Klamath Mountains. Ecological Applications 13:704-719.

Vankat, J.L. and J. Majors 1978. Vegetation changes in Sequoia National Park, California. Journal of Biogeography 5:377-402.

Weatherspoon, C.P. 1996. Fire-silvicultural relationships in Sierra forests. In Sierra Nevada Ecosystem Project Final Report to Congress, Vol. 2: Assessments and Scientific Basis for Management Options. Centers for Water and Wildland Resources, University of California, Davis, pp. 1167-1176.

Chapter 2. Resident and Neotropical Migratory Bird Response to Aspen Enhancement on the Lassen National Forest

Photo by Kevin Cole

Ryan D. Burnett & Alissa Fogg PRBO Conservation Science

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Lassen National Forests - 2009

Background and Introduction

In the Sierra Nevada, with extensive livestock grazing and the absence of regular fire, aspen are often out-competed by conifers (Mueggler 1985). As a result, the health of aspen has deteriorated and its extent throughout western North America has been reduced as much as 96% (Bartos and Campbell 2001). Aspen inventories and assessments on the Lassen National Forest found the vast majority of aspen stands to be in poor health and in need of management actions to avoid further degradation or complete stand loss. As a result, the forest has implemented strategies to restore aspen habitat by removing competing conifers and excluding livestock grazing (Jones et al. 2005). Aspen habitat in western North America can support a disproportionately rich and abundant avian community compared to the surrounding habitats (Flack 1976, Winternitz 1980, Mills et al. 2000, Griffis-Kyle and Beier 2003). Several bird species demonstrate a strong affinity with aspen, including Northern Goshawk (Accipiter gentilis), Red-naped and Red-breasted Sapsuckers (Sphyrapicus nuchalis/ruber), Dusky Flycatcher (Empidonax oberholseri), Warbling Vireo (Vireo gilvus), Swainson’s Thrush (Catharus ustulatus), and MacGillivray’s Warbler (Oporornis tolmiei) (Salt 1957, Flack 1976, Finch and Reynolds 1988, Heath and Ballard 2003, Richardson and Heath 2004). In 2004, PRBO began an adaptive management based project monitoring birds across aspen habitat on the Eagle Lake and Almanor Ranger Districts of the Lassen National Forest. The primary objective of this study is to guide and evaluate aspen restoration treatments by monitoring the response of a suite of landbird species associated with a broad range of aspen habitat characteristics. In this report we incorporate results from 2009 into those from 2004 – 2008 and use the knowledge gained from this additional information to help guide future restoration treatments and long-term management of aspen habitat on the Lassen National Forest.

Project Area All avian survey work was conducted on the Lassen National Forest in the Eagle Lake and Almanor Ranger Districts at the junction of the Sierra Nevada and Cascade Mountains of California (Lat 400 N, Long 1200 W). Sites ranged in elevation from approximately 1500 – 2000 meters (Figure 1).

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Lassen National Forests - 2009

Methods Aspen Sampling Design For all aspen sites we used GIS layers containing polygons of known aspen stands based upon aspen inventories conducted by Forest Service staff. In the Eagle Lake Ranger District (ELRD) we selected sites non-randomly that represent the range of conditions in which aspen are found throughout the District. We limited our selection to areas that could be covered by one observer in a four-hour morning count window and that contained enough acres of aspen habitat to fit a minimum of 4 point count stations with at least 220 meter spacing between points. We attempted to maximize the number of post-treatment sites, which were limited in number, as they could provide us with information on bird response to aspen treatments that were already five to nine years old. The transects with treated stands on the ELRD in 2009 included Harvey Valley, Pine Creek, Martin Creek, Feather Lake, and Butte Creek. In the Almanor Ranger District (ARD) we selected sites that were within proposed aspen enhancement projects (e.g., Minnow – Coon Hollow, Creeks II – Ruffa, Brown’s Ravine, Feather – West Dusty 1-3, Lott’s – Philbrook/Coon Hollow, and Mini – Robber’s Creek) and established points with at least 220 meter spacing in delineated aspen polygons. Two additional transects, Willow Creek and West Dusty 4 were once part of proposed projects but were dropped for various reasons. A total of 6 points (four points on the West Dusty 3 transect, one point on the West Dusty 1 transect, and one point on the Willow Creek transect) were treated as of the 2009 breeding season on the ARD. On both districts we attempted to maximize the number of points within the delineated aspen stands in the areas selected. In some areas where stands were not in high densities, we limited transect size to allow for the extra time to walk between stands in order to allow for completion within the limited morning hours allowed by the standardized protocol. Generally, the first stand chosen was the one closest to the nearest road. Once the first stand was chosen, the next closest stand that was at least 200 meters from the previous was selected, and so on. All sites were selected without previous knowledge of the local micro habitat attributes or condition.

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Lassen National Forests - 2009

Survey Protocol Standardized five minute unlimited distance variable circular plot point count censuses (Reynolds 1980, Ralph et al. 1993) were conducted at 181 stations along 18 transects in 2009 (Table 1, Figure 1, and Appendix 1). All birds detected at each station were recorded along with the exact distance from the observer where it was first detected (to the nearest meter). Birds flying above the station in transit but not observed landing were recorded separately. The method of initial detection (song, visual or call) for each individual was recorded. Counts began around local sunrise and were completed within four hours. Each transect was surveyed twice between 15 May and 1 July in each year, including 2009 (Table 1). An electronic range finder was used to assist with distance estimation at each point count station and all observers had previous songbird field work experience and went through intense three week training on bird identification and distance estimation.

Table 1. Aspen point count transects, ranger district, number of stations, and dates surveyed in 2009 in Lassen National Forest. Site Name # of Ranger Date, 1st Survey Date, 2nd Survey Stations District Brown’s Ravine Aspen 4 Almanor 6/14/2009 6/26/2009 Coon Hollow Aspen 14 Almanor 6/14/2009 7/1/2009 Philbrook Aspen 10 Almanor 6/14/2009 7/1/2009 Robber’s Creek Aspen 16 Almanor 5/28/2009 6/23/2009 Ruffa Aspen 12 Almanor 6/14/2009 7/1/2009 West Dusty Aspen 1 10 Almanor 5/26/2009 6/21/2009 West Dusty Aspen 2 6 Almanor 5/28/2009 6/24/2009 West Dusty Aspen 3 8 Almanor 5/26/2009 6/24/2009 West Dusty Aspen 4 8 Almanor 5/26/2009 6/21/2009 Willow Creek Aspen 9 Almanor 5/28/2009 6/21/2009 Butte Creek Aspen 8 Eagle Lake 5/27/2009 6/30/2009 Crazy Harry Aspen 7 Eagle Lake 5/29/2009 6/30/2009 Feather Lake Aspen 5 Eagle Lake 5/29/2009 6/30/2009 Harvey Valley Aspen 15 Eagle Lake 5/28/2008 6/20/2008 Lower Pine Creek Aspen 12 Eagle Lake 5/27/2009 6/22/2009 Martin Creek Aspen 11 Eagle Lake 5/25/2009 6/29/2009 Pine Creek Aspen 14 Eagle Lake 5/27/2009 6/22/2009 Susan River Aspen 12 Eagle Lake 5/29/2009 6/29/2009

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Lassen National Forests - 2009

Analyses Avian community point count analysis was restricted to a subset of the species encountered. We excluded species that do not breed in the study area as well as those that are not adequately sampled using the point count method (e.g., waterfowl, kingfisher, and raptors). We also excluded European Starling and Brown-headed Cowbird from analysis of species richness and total bird abundance because they are invasive species regarded as having a negative influence on the bird community. However, we did investigate the abundance of these two species separately.

Species richness We present species richness as the average number of species detected within 50 meters per point across visits within a year for the species adequately sampled using the point count method.

Total Bird Abundance The index of total bird abundance is the mean number of individuals detected per station per visit. This number is obtained by dividing the total number of detections within 50 meters by the number of stations and the number of visits.

Index of Species Abundance An index of the abundance of species was calculated as the total detections of a given species within 50m of an observer per point count visit. For sites with multiple years (most) we summed the detections and then divided by total visits across years versus averaging the means for each year.

Statistical Tests We employed a suite of statistical tests in comparing treated aspen to untreated aspen. Negative binomial regression was used to test for differences in indices of abundance of individual species between treated and untreated aspen stands; while linear regression was used to compare the community indices of species richness and total bird abundance. The test statistic (F for linear & Likelihood Ratio for negative binomial) and

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Lassen National Forests - 2009

p-values are presented. For the analysis of trends, linear regression was used with year as the independent variable and we included a quadratic term for year if the linear fit was poor. F-tests were used to evaluate the addition of the quadratic term. For all tests significance was assumed at an α = 0.05 level. Stata 10.0 statistical software was used to conduct all statistical analyses (Stata Corp 2007).

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Figure 1. Location of PRBO Aspen point count stations in the Lassen National Forest surveyed in 2009.

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Results In 2009, total bird abundance in aspen stands monitored across the two ranger districts ranged from a high of 7.83 at Ruffa Aspen to a low of 2.86 at Crazy Harry, and species richness ranged from 10.67 at Ruffa Aspen to 4.29 at Crazy Harry (Table 2). The mean total bird abundance by transect in 2009 was 5.29 while the mean species richness was 7.23. In comparison, total bird abundance in upland unburned habitat in the Plumas- Lassen study area in 2009 was 5.08 and species richness was 6.37. We compared the total bird abundance and species richness at untreated aspen sites in the ARD to untreated aspen sites in the ELRD in 2009. Species richness was 7.98 in the ARD and 6.60 in the ELRD. Total bird abundance in the ARD was 5.84 compared to 4.90 in the ELRD (Figure 2); these differences were not statistically significant. When sites in both ranger districts that have been treated were included, both species richness and total bird abundance decreased slightly in both districts but these changes were not statistically significant (Figure 2). When data from all years were combined, total bird abundance and species richness were higher at treated sites compared to untreated sites on the Eagle Lake Ranger District between 2006 and 2009 (Figure 3). Across this four year period, total bird abundance averaged 5.54 at treated sites and 4.53 at untreated sites (F = 4.25, p = 0.04). Species richness at treated sites averaged 6.99 compared to 6.33 at untreated sites (F = 0.81; p<0.37).

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Table 2. Mean per point total bird abundance (detections/point/visit) and species richness (within 50 m of observers) at aspen sites surveyed in the Lassen National Forest from 2004 – 2009. Sites not surveyed are represented by double dashes. Coon Hollow and Philbrook transects were surveyed only once in 2008 due to fire access restrictions, thus they were not included in 2008 figures. Station Total Bird Abundance Species Richness 2004 2005 2006 2007 2008 2009 2004 2005 2006 2007 2008 2009 Ruffa Aspen 5.72 7.11 5.92 6.88 6.33 7.83 7.56 7.33 7.50 8.92 8.42 10.67 Brown’s Ravine 2.38 3.25 4.13 3.75 2.75 5.63 2.75 5.25 6.25 5.00 4.25 7.75 Butte Creek 4.63 5.81 7.31 5.69 5.50 7.13 5.75 8.00 9.63 8.38 7.75 8.63 Coon Hollow ------4.75 -- 6.86 ------6.71 -- 8.43 Crazy Harry 4.50 4.00 5.43 3.64 3.57 2.86 6.43 5.43 8.00 5.85 5.71 4.29 Feather Lake 4.60 7.40 5.30 9.50 8.00 4.80 6.40 7.20 5.80 7.80 7.80 6.20 Harvey Valley 3.47 3.03 5.93 4.17 2.43 4.50 4.93 4.47 6.93 4.67 3.47 6.13 Lower Pine Creek 4.00 2.67 4.04 4.67 3.96 5.21 5.75 4.42 5.92 6.83 6.17 7.00 Martin Creek 3.78 4.18 3.91 6.32 5.86 3.73 5.09 5.45 5.27 8.00 8.36 5.27 Philbrook ------3.65 -- 6.10 ------5.30 -- 8.80 Pine Creek 4.60 4.57 5.90 5.04 4.71 4.36 5.93 6.43 7.21 7.00 6.86 6.29 Robber’s Creek -- -- 5.72 5.78 5.09 4.94 -- -- 7.63 7.31 7.63 7.12 Susan River 3.67 3.13 3.09 4.92 1.29 5.58 4.75 5.00 4.50 6.50 2.25 7.83 West Dusty 1 -- -- 3.75 4.30 3.00 3.80 -- -- 5.50 6.80 5.00 5.30 West Dusty 2 -- -- 3.33 3.67 4.08 3.83 -- -- 4.00 3.67 5.67 5.50 West Dusty 3 -- -- 3.63 3.81 3.19 4.63 -- -- 5.50 5.63 5.38 6.38 West Dusty 4 -- -- 4.75 5.25 4.56 6.56 -- -- 6.75 7.88 5.75 8.63 Willow Creek -- -- 4.28 5.44 4.61 6.00 -- -- 5.33 7.22 6.78 8.44 Total 4.16 4.67 5.36 5.32 4.42 5.29 5.53 5.90 6.68 6.79 6.08 7.23

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Figure 2. Mean per point species richness (per year) and total bird abundance (per visit) based on detections within 50 meters of observers at treated and untreated aspen sites on Almanor and Eagle Lake ranger districts in 2009 with standard error.

Almanor vs. Eagle Lake 2009

9 Almanor Untreated 8 Almanor Total 7 Eagle Lake Untreated

6 Eagle Lake Total

0 Species Richness Total Bird Abundance

Figure 3. Mean per point species richness and total bird abundance at treated and untreated aspen sites on the Eagle Lake Ranger District from 2006 – 2009 compared to coniferous forest in the Plumas-Lassen study area from 2003 – 2006 with standard error.

Treated vs. untreated aspen

8.00

7.00

6.00

5.00 Treated Aspen 4.00 Untreated Aspen Conifer Forest 3.00

2.00

1.00

0.00 Species Richness Total Bird Abundance

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Species richness decreases substantially in 2009 at treated sites on ELRD to its lowest value since the beginning of the study (Figure 4). Including a quadratic term for year improved model fit (F = 8.2, p = 0.005). Species richness at untreated sites on ELRD continued to show a significant increasing linear trend (F = 9.6, p < 0.002) between 2004 and 2009. Total bird abundance from 2004 through 2009 at treated sites also decreased to its lowest value since the beginning of the study and including a quadratic term for year improved model fit for this metric as well (F = 10.0, p = 0.002). Untreated sites continued to show a significant increasing linear trend (F = 6.63, p = 0.01).

Figure 4. Mean per point species richness (with standard error) at treated and untreated aspen sites from 2004 -2009 in Eagle Lake Ranger District (Lassen National Forest) with standard error and fitted linear and quadratic trend lines.

Species Richness

# of Species/Point # 3 Treated Untreated 2

0 2004 2005 2006 2007 2008 2009

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Figure 5. Total bird abundance per point count visit (with standard error) by year at treated and untreated aspen sites from 2004 - 2009 on the Eagle Lake Ranger District (Lassen National Forest) with standard error and fitted linear and quadratic trends.

Total Bird Abundance

7 t 6

2 Treated # of Individuals/Point/Visi Untreated 1

0 2004 2005 2006 2007 2008 2009

We investigated an index of the abundance of ten of the twelve previously identified aspen focal species (Burnett in press), at treated aspen, untreated aspen, and conifer forest across the six-year study period in both ranger districts. We also included Mountain Chickadee, another potential focal species. There were not adequate detections of Swainson’s Thrush and Olive-sided Flycatcher – the remaining two focal species – to include them in the analysis. Six of the eleven species were significantly more abundant in treated aspen than untreated aspen; each of these six species were also more abundant in aspen of any kind compared to coniferous forest in the region (Table 3, Figure 6). Red-breasted Sapsucker, Hairy Woodpecker, Mountain Bluebird, Tree Swallow, Mountain Chickadee and Chipping Sparrow were all significantly more abundant in treated aspen than untreated aspen. Additionally, total bird abundance was significantly greater in treated stands compared to untreated stands while species richness was similar. Western Wood-Pewee and Warbling Vireo showed a small non-significant difference between treated and untreated aspen though these species were far more abundant in aspen stands than conifer

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

forest. Only two focal species, Dusky Flycatcher and MacGillivray’s Warbler, remained more abundant in untreated than treated aspen, with a significant difference for MacGillivray’s Warbler, and both were similarly abundant in conifer forest as in aspen.

Table 3. Species Richness, total bird abundance, and an index of the abundance of ten aspen focal species at treated and untreated sites across the Lassen National Forest, 2006- 2009. P-value is from linear (species richness & total bird abundance) or negative binomial regression (all other metrics) comparing treated to untreated aspen. Means from conifer forest in the Plumas-Lassen Administrative Study from 2003-2006 are also presented for comparison. Treated Untreated Conifer Aspen Aspen P Forest Species Richness 6.94 6.63 0.23 5.47 Total Bird Abundance 5.48 4.76 <0.01 4.08 Red-breasted Sapsucker 0.22 0.15 0.03 0.03 Hairy Woodpecker 0.15 0.08 0.01 0.03 Western Wood-Pewee 0.17 0.16 0.66 0.02 Dusky Flycatcher 0.16 0.20 0.29 0.26 Warbling Vireo 0.52 0.50 0.75 0.09 Tree Swallow 0.42 0.03 <0.01 0.01 Mountain Chickadee 0.62 0.44 <0.01 0.28 Mountain Bluebird 0.11 0.00 <0.01 0.00 Oregon Junco 0.50 0.49 0.82 0.36 Chipping Sparrow 0.20 0.07 <0.01 0.01 MacGillivray's Warbler 0.07 0.14 0.01 0.11

We investigated the effect of time since treatment on total bird abundance and species richness during 2004-2009 for all aspen sites on the Lassen National Forest while controlling for year. When all treated and untreated sites are included (with those that have not been treated coded as zero) there is a significant positive effect (F = 15.0, p<0.01) of time since treatment on total bird abundance (Figure 7). When untreated sites were not included there was no effect of time since treatment (F = 0.07, p = 0.79) on total bird abundance. For species richness, the effect of time since treatment was positive and significant when untreated sites were included (F = 4.96, p = 0.03; Figure 8), but was not when they were excluded (F = 1.41, p = 0.24). This pattern is consistent with what we have observed in previous years.

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Figure 6. Abundance per point count visit ± standard error for the seven aspen focal species with a significant difference in abundance (p<0.05) between treated and untreated aspen stands in the Lassen National Forest from 2006-2009. Conifer habitat indices are shown for comparison using data from the Plumas-Lassen Administrative Study from 2003 – 2006. 0.80 Treated Vs. Untreated Aspen 0.70 Treated Aspen Untreated Aspen 0.60 Conifer Forest

0.50

0.40

0.30 Detections pervisit

0.20

0.10

0.00 Red-breasted Hairy Tree Sw allow Mountain Mountain Chipping MacGillivray's Sapsucker Woodpecker Chickadee Bluebird Sparrow Warbler

The time since aspen stands had been treated had a significant effect on the abundance of six of the ten focal species (Figure 9). For Red-breasted Sapsucker and Chipping Sparrow the effect was positive and the best fit was linear. For each of the other five species the effect was more complex. For Hairy Woodpecker, Tree Swallow, Mountain Bluebird, and Dusky Flycatcher, the best fit model was one with a quadratic effect of treatment. For all of these except Dusky Flycatcher there was an increasing trend peaking in the four to five year post treatment period followed by a significant decrease after that. Dusky Flycatcher was the only species to show a negative effect of time since treatment; it decreased in the years immediately following treatment but showed an increase in abundance in the longest time since treatment interval. MacGillivray’s Warbler also showed a weakly significant (p = 0.06) negative linear trend with time since treatment.

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Figure 9. The mean abundance per point count visit with standard error and predicted values for the six focal species showing a significant effect of time since treatment from 2004 - 2009. Graphs show time since treatment in intervals for illustrative purposes but regression was conducted with all data. All aspen sites surveyed on the Lassen National Forest are included. All untreated sites were coded as zero years post treatment.

Red-breasted Sapsucker Hairy Woodpecker t t 0.4 0.4 0.3 0.3

0.2 0.2 Visit Visit 0.1 0.1 0 0 Detections/Point Coun Detections/Point Coun 0 1 to 2 3 to 4 5 to 6 >6 0 1 to 2 3 to 4 5 to 6 >6 Years Post Treatment Years Post Treatment

Tree Swallow Mountain Bluebird t t 1 0.3 0.8 0.25 0.2 0.6 0.15

Visit 0.4 Visit 0.1 0.2 0.05 0 0 Detections/Point Coun Detections/Point Coun 0 1 to 2 3 to 4 5 to 6 >6 0 1 to 2 3 to 4 5 to 6 >6 Years Post Treatment Years Post Treatment

Dusky Flycatcher Chipping Sparrow t t 0.4 0.4

0.3 0.3 0.2 0.2 Visit Visit 0.1 0.1 0 0 Detections/Point Coun Detections/Point Coun 0 1 to 2 3 to 4 5 to 6 >6 0 1 to 2 3 to 4 5 to 6 >6 Years Post Treatment Years Post Treatment

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

In Harvey Valley, species richness and total bird abundance increased following treatment (Figure 10). Species richness increased at treated sites 19% over pre-treatment levels while untreated sites increased 11%. Total bird abundance increased 14% at treated sites following treatment while it decreased 11% at untreated sites. Due to relatively small sample size (15 total points) none of these differences were statistically significant.

Figure 10. Species richness and total bird abundance at six reference and nine treated sites before (2004-2007) and after (2009) treatment with 95% confidence intervals for the Harvey Valley Aspen transect. All treatments were implemented in the winter of 2008 but not completed until after the breeding season, so 2008 was excluded from analysis.

Harvey Valley Species Richness

9 8 7 6 5 4 3 2

Species/Point Year Per 1 0 Reference Reference Treated Treated

Before After Before After

Harvey Valley Total Bird Abundance

7 6 5 4 3 2 Detections/Visit 1 0 Reference Reference Treated Treated

Before After Before After

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Similar to Harvey Valley, treated stands in the Feather aspen project on the ARD showed a modest increase in 2009 the first year after treatment was implemented (Figure 11). Species richness increased at treated sites 17% while it declined 4% at untreated sites. Total bird abundance increased 24% at treated sites while it increased 11% at untreated sites. Again, with small sample sizes none of these differences were statistically significant.

Figure 11. Species richness and total bird abundance at nine treated aspen sites and five untreated aspen sites in the Feather aspen restoration project with 95% confidence intervals. All sites were treated in the fall of 2008.

Species Richness West Dusty 3

10 9 8 7 6 5 4 3 2

Species/Point per Year 1 0 Reference Reference Treated Treated

Before After Before After

Total Bird Abundance West Dusty 3

8 7 6 5 4 3 2

Individuals/Point Visit 1 0 Reference Reference Treated Treated

Before After Before After

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

At the Pine Creek aspen site, the trends in species richness and total bird abundance have been decreasing in the last three years from highs recorded in 2006 and in 2009 were at similar levels to those recorded in 2004 (Figure 12). The inclusion of a quadratic term in the model did significantly improve the fit compared to a linear model.

Figure 12. Mean per point species richness and total bird abundance (<50m from observers) at the Pine Creek Aspen transect from 2004 – 2009 with 95% confidence intervals. The majority of treatment was implemented in the winter of 2003/2004, fall 2006, and winter 2007/2008.

Pine Creek Aspen

10 9 8 7 6 5 4 3 Individuals/Visit

Species Per Point or or Point Per Species 2 Species Richness 1 Total Bird Abundance 0 2004 2005 2006 2007 2008 2009 Year

Discussion Aspen habitat on the Lassen National Forest harbors greater total bird abundance, species richness, and abundance of almost all of the aspen focal species compared to conifer-dominated forest in the region. On average, aspen habitat on the ARD harbored greater species richness and total bird abundance compared to the ELRD, though there continues to be considerable site to site and annual variation in these indices as well as in the abundance of individual species.

Treated vs. Untreated In the ELRD, the short term response of the avian community to aspen treatments has been decidedly positive. From 2004 - 2009 species richness and total bird abundance

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

showed a significant increase at both treated and untreated aspen. However, in 2009 these consistent increasing trends showed a downturn at treated sites while they continued to increase at untreated sites. The fit of the trend at untreated site is not as good as that for treated sites with considerable annual variation. The untreated sites used as reference sites have almost all been released from livestock grazing pressure which has been shown to result in an increase in bird species richness and the abundance of many of our aspen focal species (Earnst et al. 2006). Thus they may be undergoing passive restoration resulting in the observed increasing trends. As for the decline in richness and abundance at treated sites in 2009, it appears as though the short-term benefits of aspen treatments may be rather short-lived. However, due to potential bias in how treated sites were selected and the lack of true controls (untreated sites have been switching into the treated sample as more sites get treated) and the potential bias in how sites are selected for treatment by the Forest Service (selecting poorer quality sites with unhealthier aspen), we continue to advise some caution in interpreting these trends. However, based on several recently treated sites, the pattern of an immediate increase following treatment followed by a slow but steady declines remains consistent. For example, Harvey Valley, treated in winter 2007-2008 showed an increase in richness and abundance in 2009 compared to the mean from the four years prior to treatment as did West Dusty 3 (part of the Feather project treated in 2008) on the Almanor Ranger district. However, Pine Creek showed a substantial decrease in 2009 from previous years. The decline at this site may be a result of the riparian areas being treated in 2007, further reducing the habitat for conifer associated species; but we also observed a decline here in many of the focal species in 2009. We also observed decreases in these metrics at Feather Lake in 2009. We had originally hypothesized treatments would result in a decrease in species richness and abundance in the lag between the loss of foliage volume and structural diversity from conifer removal and the time it takes for aspen to regenerate. As the Pine Creek and Feather Lake represent 45% of our treated sample and the majority of our older sites, the decreases observed here in 2009 appear to be driving the overall trends. Continued monitoring will help provide greater insight into these patterns in order to more fully determine the response of the avian community to treatments over time.

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

While we documented declines of many focal species in treated stands in 2009, the overall abundance of most of the focal species from 2006 – 2009 are still higher at treated sites than at untreated. All of the seven focal species that were significantly more abundant in treated aspen compared to untreated aspen were also significantly more abundant in treated aspen than conifer forest. Chipping Sparrow, declining at a rate of 3.4% per year from 1968-2007 in the Sierra Nevada (Sauer et al. 2008) have been increasing significantly in treated aspen stands and that patterned continued to hold in 2009. This species often nests in understory trees in areas with a substantial herbaceous layer where it forages on insects and seeds (Middleton 1998). Thus, treated aspen stands appear to be ideal habitat for this species, which is very rare in conifer-dominated forest in the region. Likewise, Mountain Bluebird and Tree Swallow are all but absent from conifer forest and untreated aspen, but are fairly common to abundant (respectively) in treated aspen. Mountain Bluebird has been declining over the past 40 years in the Sierra Nevada at a rate of 2.5% per year, though due most likely to their rarity this trend is not significant (Sauer et al. 2008). All of the aspen focal species are more abundant or as abundant in treated aspen compared to untreated aspen with the exception of MacGillivray’s Warbler. Restoring dense willow and alder cover in riparian habitat within aspen stands will be key to improving habitat for MacGillivray’s Warbler – as they are rarely found in aspen stands away from riparian areas. They are quite abundant at Martin Creek in the treated and fenced stand with a dense understory. Removing conifers from riparian zones that can support deciduous riparian vegetation and reducing the grazing in order to allow a dense understory to return will benefit this species and likely a number of bird species that rely on this unique but limited habitat. Aspen habitat often supports a diverse and abundant guild of cavity nesting species, with many studies showing cavity nesters disproportionately select aspen trees for nesting (Li and Martin 1991, Dobkin et al. 1995, Martin and Eadie 1999, Martin et al. 2004). While aspen often contain relatively high numbers of natural cavities, secondary cavity nesting species have been found to nest predominantly in woodpecker created holes in both live aspen and aspen snags (Li and Martin 1991, Dobkin et al. 1995, Martin and Eadie 1999). Both Red-breasted Sapsucker and Hairy Woodpecker continued to be

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

significantly more abundant in treated aspen than untreated aspen or conifer forest in the region. At numerous treated aspen – including those at Feather Lake, Butte Creek, Pine Creek, and Martin Creek – we confirmed active woodpecker nest cavities within treated stands. In 2008 we documented seven species of woodpecker present during one visit to the Pine Creek transect (Hairy, Downy, White-headed, Black-backed, Pileated, Northern Flicker, and Red-breasted Sapsucker). Removing encroaching conifers from within and surrounding aspen stands, resulting in the expansion of stands and increased density of large diameter aspen stems over time, should increase habitat for woodpeckers. There is little doubt that aspen supports far greater abundance of woodpeckers than coniferous forest and that treating aspen results in even greater increases in these species of management interest. In turn, woodpeckers are a critical component of the aspen community as the source of cavities for an abundant and diverse group of secondary cavity nesting birds, many of which use these aspen areas in relatively high numbers (e.g., Mountain Bluebird, Tree Swallow, and Mountain Chickadee).

Time Since Treatment The time since aspen stands had been treated continued to show a generally positive but complex effect on many of the focal species once 2009 data, including five treated sites on the ARD were added. The best fit models for four of the six species showing a significant effect of time since treatment included a quadratic term. For three of these species their abundance peaked in the three to four years post-treatment time period and then declined in the following time intervals. This suggests the immediate positive increase after aspen treatments may be relatively short-lived for at least some species and mimics the general pattern observed with species richness and total bird abundance. However, it is important to remember that that the post-treatment sample is relatively small (42 sites in 2009) and any inherent biases in how sites were chosen for treatment could easily be magnified in this analysis. These patterns suggest that no one aspen condition or post-treatment time period is ideal for all species. The conditions created immediately following aspen treatments may be mimicking the structure found in natural post-disturbance habitat that often supports greater numbers of some of these species (Raphael et al. 1987). Though Hairy

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Woodpecker, Tree Swallow, and Mountain Bluebird showed marked declines at sites over four years post-treatment, each was more abundant in these older sites than they were in untreated aspen. These results continue to support the notion that management of aspen habitat should consider the importance of disturbance and the early successional habitat in which it results.

Conclusions Our results from 2009 continue to suggest that aspen treatments employed on the LNF are having a positive effect on the aspen breeding bird community. Key species such as Red-breasted Sapsucker, Mountain Bluebird, and Chipping Sparrow all appear to have had a short-term positive response to treatment. Based on these and previous results, we believe that treatments that increase the size and health of aspen stands will be highly beneficial to aspen focal bird species in the Lassen National Forest in the long-term and should be a top priority of land managers here. We also recognize the value of continuing the monitoring of landbird communities in treated aspen habitat in order to better understand the complex patterns we have observed in recent years as treated stands mature.

Acknowledgements Funding for our Aspen project was provided by the Lassen National Forest and Herger Feinstein Quincy Library Group Forest Recovery Act monitoring funds. We especially would like to thank Coye Burnett, Tom Frolli, Bobette Jones, Tom Rickman, and Mark Williams of the Lassen National Forest - for their support and assistance with this project. We also wish to thank Tim Guida, crew leader, and Nathan Fronk and Luke Owens, our 2009 field crew.

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

Literature Cited

Bartos, D.L. and R.B. Campbell, Jr. 2001. Landscape dynamics of aspen and conifer forest. In Sustaining aspen in Western Landscapes: Symposium Proceedings. Grand Junction, CO: Rocky Mountain Research Station. USDA Forest Service. RMRS -18:5-14.

Burnett, R.D. In press. Integrating Avian Monitoring into Forest Management: Pine-Oak and Aspen Enhancement on the Lassen National Forest. USFWS Technical Report.

Dobkin, D. S., A. C. Rich, J. A. Pretare, and W. H. Pyle. 1995. Nest-site relationships among cavity-nesting birds of riparian and snowpocket aspen woodlands in the northwestern Great Basin. Condor 97:694-707.

Earnst, S.L., J.A. Ballard, and D.S. Dobkin. 2005. Riparian songbird abundance a decade after cattle removal on Hart Mountain and Sheldon National Wildlife Refuges. PSW-GTR 191:550-558.

Finch, D.M. and R.T. Reynolds. 1987. Bird response to understory variation and conifer succession in aspen forests. Pages 87-96, In J. Emmerick et al. eds. Proceedings of issues and technology in the management of impacted wildlife. Thorne Ecological Institute, Colorado Springs, CO.

Flack, J.A. Douglas. 1976. Bird populations of aspen forests in western North America. Ornithological Monographs No. 19. The American Ornithologist’s Union.

Heath, S.K. and G. Ballard. 2003. Patterns of breeding songbird diversity and occurrence in riparian habitats of the Eastern Sierra Nevada. In California Riparian Systems: Processes and Floodplain Management, Ecology, and Restoration. 2001 Riparian Habitats and Floodplains Conf. Proc. (P. M. Faber, ed.). Riparian Habitat Joint Venture, Sacramento, CA.

Jones, B.E., T.H. Rickman, A. Vasquez, Y. Sado, K.W. Tate. In press. Removal of invasive conifers to regenerate degraded aspen stands in the Sierra Nevada. Restoration Ecology 13:373-379.

Li, P., and T. E. Martin. 1991. Nest-site selection and nesting success of cavity-nesting birds in high elevation forest drainages. Auk 108:405-418.

Martin, K., K. E. H. Aitken, and K. L. Wiebe. 2004. Nest-sites and nest webs for cavity- nesting communities in interior British Columbia: nest characteristics and niche partitioning: Condor. 106 5–19.

Martin, K. and J.M. Eadie. 1999. Nest webs: A community wide approach to the

Chapter 2. Aspen Enhancement PRBO Avian Monitoring in the Plumas & Lassen National Forests - 2008

management and conservation of cavity nesting forest birds. Forest Ecology and Management 115:243-257.

Mueggler, W.F. 1985. Forage. In Aspen: Ecology and management in the Western United States. USDA Forest Service General Technical Report RM-119:129-134.

Middleton, Alex L. 1998. Chipping Sparrow (Spizella passerina), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/334

Ralph, C. J., G. R. Geupel, P. Pyle, T. E. Martin, & D. F. DeSante. 1993. Field Methods for Monitoring Landbirds. USDA Forest Service Publication, PSW-GTR 144, Albany, CA.

Raphael, M.G., Morrison, M.L., Yoder-Williams, M.P. 1987. Breeding bird populations during twenty five years of post-fire succession in the Sierra Nevada. The Condor 89, 614-626.

Reynolds, R.T., J.M. Scott, and R.A. Nussbaum. 1980. A variable circular plot method for estimating bird numbers. Condor 82:309:313.

Richardson, T.W. and S.K. Heath. 2005. Effects of conifers on aspen breeding bird communities in the Sierra Nevada. Transactions of the Western Section of the Wildlife Society 40: 68 – 81.

Sauer, J. R., J. E. Hines, and J. Fallon. 2008. The North American Breeding Bird Survey, Results and Analysis 1966 - 2007. Version 10.13.2007. USGS Patuxent Wildlife Research Center, Laurel, MD.

Stata Corp. 2007. Intercooled Stata 10.0 for Windows. Stata Corp. LP College Station, TX.

Chapter 3. Resident and Neotropical Migratory Bird Monitoring in Mountain Meadows: 2009 Report

Ryan D. Burnett PRBO Conservation Science

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Background and Introduction

Mountain meadows are among the most important habitats for birds in California (Siegel and DeSante 1999, Burnett and Humple 2003, Burnett et al. 2005); they support several rare and declining species and are utilized at some point during the year by almost every bird species that breeds in or migrates through the Sierra Nevada. Meadows also perform a vital role as watershed wetlands that store and purify drinking water for millions of Californians. And yet, most of these meadows are in a degraded state and their value for water storage and as critical habitat for birds and other wildlife has been dramatically reduced. In the Sierra Nevada, meadows have been heavily degraded or lost due to well over a century of human activities including flooding, diversions, vegetation removal, and overgrazing (SNEP 1996, Siegel and DeSante 1999). As far back as 1869, John Muir lamented about the destruction of Sierra meadows by man, “….but as far as I have seen, man alone, and the animals he tames, destroy these gardens.” Indeed few, if any, meadows in the Sierra remain unaltered by human activities. The meadows that do remain are in a compromised state and they are owned by a diverse set of interests including private industry and utilities, state and federal agencies, and private ranches. Though they have been altered, a number of meadows in the Feather River watershed support populations of many declining and threatened riparian meadow bird species, including Sandhill Crane, Swainson’s Thrush, Yellow Warbler, and Willow Flycatcher. The area also supports breeding populations of 11 of the 16 California Partners in Flight Riparian Focal Species (Humple and Burnett 2004, RHJV 2004). With its high diversity and abundance of meadow bird species, including the largest population of Willow Flycatcher in the Sierra Nevada region (Humple and Burnett 2004), the Feather River watershed is a conservation hotspot for meadow birds. Meadow conservation and management in the Feather River watershed and throughout the Sierra Nevada will require a collaborative effort between different land management agencies, county government, non-governmental organizations, and private landowners. In order to manage for breeding bird populations, especially listed meadow- dependent species such as Willow Flycatcher and Sandhill Crane, the Forest Service

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

needs to with the other meadow landowners in the area in order to ensure the long-term viability of these and other bird species. In this chapter we summarize results from point count surveys from meadows in the Feather River watershed in 2009, including three new sites in the Last Chance Creek watershed and one new site on the Eagle Lake Ranger District (ELRD). We use a suite of meadow focal species to compare abundance and richness metrics between meadows and provide recommendations for improving habitat for these and other species. We also briefly report on our breeding and post-breeding mist-netting efforts at wet meadow sites in the region.

Methods

Site Selection Several considerations went into selecting meadow sites we sampled. Following an inventory of 16 meadows in the Almanor Ranger District (ARD) of the Lassen National Forest (LNF) between 2000 and 2001 we selected a subset of those sites to continue long-term meadow monitoring within. We were interested in surveying sites that supported or could support a riparian deciduous shrub (willows/alders) bird community and especially those sites that had recently undergone management changes (e.g. active restoration and/or removal of grazing). With these two considerations in mind we attempted to choose sites that represented a range of elevations and habitat conditions. With this strategy, we believe the sites selected are not totally representative of the range of meadow conditions in the ARD area but represent some of the higher quality riparian meadow bird habitat in the area. Sites within the Last Chance Watershed were added within areas that have been restored or are slated to be restored in the next couple of years. The Pine Creek Valley transect was established at the request of the ELRD in order to investigate the difference in the avian community within and outside of a grazing exclosure.

Point Count Censuses Point count data allow us to measure secondary population parameters such as relative abundance of individual bird species and species richness. This method is useful for making comparisons of bird communities across time, locations, habitats, and land-

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Figure 1. PRBO Northern Sierra meadow point count sites surveyed in 2009.

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

use treatments. Standardized five-minute multiple distance band point count censuses (Reynolds et al. 1980, Ralph et al. 1995) were conducted at each of 94 stations along nine transects in 2010 within the greater ARD area, 54 points in the Last Chance Creek Watershed in eastern Plumas County, and 15 points in the Pine Creek Valley on the ELRD for a total of 162 point count stations (Table 1). Point count stations were a minimum of 50 meters from meadow edges where feasible; if the riparian corridor was less than 100 meters wide, points were placed equidistant from each edge, and in most cases points were located within 50 meters of stream channel (where they existed). At each site points were spaced between 200 and 250 meters apart and were configured in a manner that maximized spatial coverage of sites.

Table 1. PRBO Northern Sierra meadow point count transects with transect codes, year established, and dates surveyed in 2009. # of Year 2009 2009 Transect Code points established 1st Visit 2nd Visit Alkali Flat ALFL 18 2009 19-Jun 27-Jun Carter Meadow CAME 7 2004 16-Jun 30-Jun Clark’s Creek CKCR 18 2009 29-May 20-Jun Fanani Meadow FAME 8 2003 28-May 17-Jun Gurnsey Creek GUCR 10 1997 1-Jun 16-Jun Humbug Valley HUVA 17 2003 10-Jun 26-Jun Lower Last Chance Creek LLCH 18 2009 13-Jun 25-Jun Pine Creek Valley PCVA 15 2009 13-Jun 22-Jun Robber’s Creek ROCR 14 2004 12-Jun 29-Jun Soldier Meadow SOME 7 2001 28-May 17-Jun West Shore Lake Almanor WSLA 13 2004 2-Jun 18-Jun Yellow Creek Riparian YCRI 12 2001 5-Jun 19-Jun Yellow Creek PG&E YCPGE 6 2008 5-Jun 19-Jun Total 163

All birds detected at each station during the five-minute survey were recorded. Detections were placed within one of six categories based on the initial detection distance from observer: less than 10 meters, 10-20 meters, 20-30 meters, 30-50 meters, 50-100 meters, and greater than 100 meters. Birds flying over the study area but not observed using the habitat were recorded separately, and excluded from all analyses. The method of initial detection (song, visual or call) for each individual was also recorded. Counts began around local sunrise and were completed within four hours. Each transect was visited twice each year between late May and the end of June. With the exception of

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Lower Last Chance Creek, Alkali Flat, and Clark’s Creek, all surveys were conducted by the author who has been conducting point counts in the Sierra Nevada for over a decade. The three other sites were surveyed by two experts in Northern Sierra bird identification that passed a double observer field test with the author prior to conducting counts. An electronic range finder was used by all observers to assist with distance estimation at each point count station.

Statistical Analysis Point count analysis was restricted to a subset of the species encountered. We excluded species that do not breed in the study area as well as those species that are not adequately sampled using the point count method (e.g., shorebirds, waterfowl, raptors, and swallows). For a number of the analyses we used a suite of meadow focal species that represent a range of meadow bird habitat conditions and as a group are likely to provide a better measure of the quality of meadow habitat than all species (Chase and Geupel 2005; Table 2).

Table 2. Avian focal species (listed in taxonomic order) for meadow monitoring in the ARD and their conservation status. California Partners in Flight Riparian Focal species are noted in bold (RHJV 2004). Species Conservation Status1 Sandhill Crane State Threatened Red-breasted Sapsucker Declining in the Sierra2; NTMB Willow Flycatcher State Endangered, USFS Sensitive, NTMB Warbling Vireo NTMB, Declining in the Western U.S. Swainson’s Thrush USFS Priority Land Bird Species, NTMB Black-headed Grosbeak NTMB Yellow Warbler State Species of Special Concern, NTMB MacGillivray's Warbler NTMB Wilson's Warbler Significant Decline in Sierra2, NTMB Song Sparrow None Lincoln's Sparrow NTMB 1NTMB = Neotropical Migratory Bird 2 from Sauer et al. 2008.

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Species richness The species richness index used here was obtained by summing the species detected within 50 meters of the observer across both visits to each point count station and then averaged across all points in the transect. Similarly, focal species richness is the same calculation but limited to the list of species in table 2. Presenting the mean species richness, as is done herein, allows for comparisons between transects or habitats consisting of different numbers of point count stations but does not provide a measure of the total number of species across an entire transect.

Indices of Abundance An index of total bird abundance, defined as the mean number of individuals detected per station per visit, was calculated for each transect. This number is obtained by dividing the total number of detections within 50 meters of the observer by the number of stations and the number of visits. The same method was employed for creating focal species abundance (the total number of individuals of all focal species combined) and for each individual focal species. Note that Sandhill Crane was did not occur within 50m of observers but would not have been included in these indices if it had as it is not adequately sampled using point counts (large territories and shy).

Results Song Sparrow was the most abundant meadow bird focal species detected from 2003 – 2009 at the Almanor area meadows with and index of abundance of 1.17, followed by Yellow Warbler at 1.04 (Figure 2). In the Last Chance Creek watershed these two species were also the most abundant focal species with indices of abundance of 0.97 and 0.74 respectively (Figure 3). Willow Flycatcher, a Forest Service sensitive and state threatened species, had an index of abundance of 0.08 in the Almanor area while this species along with Wilson’s Warbler and Lincoln’s Sparrow were not detected in the Last Chance watershed.

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Figure 2. The mean abundance (+/- standard error) of nine meadow focal species per point count visit from 2003 – 2009 across all sites combined in wet riparian meadows in the Almanor Ranger District.

Focal Species Abundance (Almanor Area)

Black-headed Grosbeak

Red-breasted Sapsucker

Willow Flycatcher

Lincoln's Sparrow

Wilson's Warbler

Warbling Vireo

MacGillivray's Warbler

Yellow Warbler

Song Sparrow

0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 Detections/Point Count Visit

Figure 3. The mean abundance (+/- standard error) of nine meadow focal species per point count visit in 2009 across all sites combined in the Last Chance Creek watershed. Note Willow Flycatcher, Lincoln’s Sparrow, and Wilson’s Warble were not detected here in 2009.

Focal Species Abundance (Last Chance Watershed)

Willow Flycatcher

Lincoln's Sparrow

Wilson's Warbler

Red-breasted Sapsucker

Warbling Vireo

MacGillivray's Warbler

Black-headed Grosbeak

Yellow Warbler

Song Sparrow

0 0.2 0.4 0.6 0.8 1 1.2 Detections per Point Count Visit

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Meadow Comparison I compared species richness, total bird abundance, focal species richness, and focal species total abundance across all sites in 2009. The mean species richness for all sites combined was 6.09. Carter Meadow had the highest avian species richness with 8.86 species per point (Figure 4). Carter Meadow was followed closely by Robber’s Creek and Yellow Creek at 8.79 and 8.75, respectively. All three of these sites had overall species richness significantly higher than the average for all sites combined. The lowest species richness was for Yellow Creek PG&E with 1.5 species per point. Other sites with significantly lower species richness than the average for all sites combined were Pine Creek Valley, Lower Last Chance Creek, Soldier Meadow, and Alkali Flat. The mean total bird abundance in 2009 for all sites combined was 6.02. Total bird abundance was highest at Carter Meadow with 9.14 detections per point per visit (Figure 5). The only other site with significantly higher total bird abundance than the mean for all sites combined was West Shore Lake Almanor at 8.35. Sites with significantly lower total bird abundance than the 2009 average were Yellow Creek PG&E at 1.5, Soldier meadow at 2.71, Pine Creek Valley at 3.20, and Lower Last Chance Creek at 3.64.

Figure 4. Avian species richness (per point per year detections <50m) at 12 meadow sites in the Northern Sierra Nevada in 2009 with 95% confidence intervals. The dashed line represents the mean for all sites combined. Four letter site codes are defined in Table 1.

Species Richness

12 11 10 9 8 7 6 5 4

Species/Point/Year 3 2 1 0 CAME FAME GUCR HUVA ROCR SOME WSLA YCRI YCPGE ALFL CKCR LLCH PCVA

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Figure 5. Total bird abundance (per point per visit detections <50m) at 12 meadow sites in the Northern Sierra Nevada in 2009 with 95% confidence intervals. The dashed line represents the mean for all sites combined. Four letter site codes are defined in Table 1.

Total Bird Abundance

4 Individuals/Point/Visit 2

0 CAME FAME GUCR HUVA ROCR SOME WSLA YCRIYCPGEALFL CKCR LLCH PCVA

The mean focal species richness for all sites combined in 2009 was 2.38. Focal species richness was highest at Fanani Meadow with 4.38 species per point (Figure 6). The only other sites with focal richness significantly higher than the 2009 average were Gurnsey Creek with 4.0 and Carter Meadow at 3.43. Lower Last Chance Creek (1.72), Alkali Flat (1.17), Yellow Creek PG&E (0.0), and Pine Creek Valley (0.0) all had focal richness significantly lower than the average. The mean focal species abundance for all sites combined in 2009 was 2.81. Focal species abundance was highest at Gurnsey Creek with 4.55 detections per point per visit followed by West Shore Lake Almanor with 4.19 (Figure 7). These meadows were the only two with significantly higher focal species abundance than the average from all sites combined. The meadows with significantly lower focal species abundance than the 2009 average were Lower Last Chance Creek (1.75), Alkali Flat (1.56), Soldier Meadow (0.93), Yellow Creek PG&E (0.0), and Pine Creek Valley (0.0).

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Figure 6. Avian meadow focal species richness (per point per year detections <50m) at 12 meadow sites in the Northern Sierra Nevada in 2009 with 95% confidence intervals. The dashed line represents the mean for all sites combined. Four letter site codes are defined in Table 1.

Focal Species Richness

2 Species/Point/Year

0 CAME FAME GUCR HUVA ROCR SOME WSLA YCRI YCPGE ALFL CKCR LLCH PCVA

Figure 7. Meadow focal species abundance (per point per visit detections <50m) at 12 meadow sites in the Northern Sierra Nevada in 2009 with 95% confidence intervals. The dashed line represents the mean for all sites combined. Four letter site codes are defined in Table 1.

Focal Species Abundance

2 Individuals/Point/Visit 1

0 CAME FAME GUCR HUVA ROCR SOME WSLA YCRI YCPGE ALFL CKCR LLCH PCVA

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

PG&E and its partners have been considering restoring a portion of Yellow Creek where it enters the valley floor in Humbug Valley. We have been monitoring birds upstream of this area on Yellow Creek since 2003. In 2008, an additional six point count stations were added at the downstream end of the existing transect in order to sample the project area (YCPGE). Using data from 2008 and 2009, I compared several avian metrics between the project area and the Forest Service land immediately above the proposed project area (Figure 8). Species richness, total bird abundance, focal richness, and the abundance of six focal species were all significantly lower in the project area. In fact, we did not detect a single focal species in two years within the project area. The primary species detected in the project were Horned Lark and Savannah Sparrow, two species associated with drier grassland habitat.

Figure 8. Avian indices along Yellow Creek comparing the proposed Feather River CRM-PG&E restoration reach with Forest Service land upstream in 2008 and 2009. Error bars are 95% confidence intervals. Note no meadow bird focal species were detected in the proposed project area in either year.

10 9 8 Project Area 7 Upstream 6 5 4 3 2 1 0 Species Total Bird Focal Yellow Song Warbling MacGillivray's Wilson's Red-breasted Richness Abundance Richness Warbler Sparrow Vireo Warbler Warbler Sapsucker

Pine Creek Valley Grassland Grazing Exclosure At the Pine Creek Valley site, species richness was slightly higher outside of the grazing exclosure and total bird abundance was greater inside the exclosure, although neither of these differences was statistically significant (Figure 10). Only the abundance of Willet and Brewer’s Blackbird – more abundant outside the exclosure - and Savannah Sparrow – more abundant inside the exclosure - were statistically significant. Wilson’s Phalarope were more than four

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

times more abundant inside of the exclosure than outside though due to the relatively limited sample size (n=15) this difference was not quite statistically significant.

Figure 10. Species richness, total bird abundance, and an index of the abundance of five species per point count station in the Pine Creek Valley grassland within and outside of a grazing exclosure in 2009. Error bars represent the 95% confidence interval.

Pine Creek Valley

6 No Grazing 5 Grazing 4

3 2

0 Species Total Bird Brewer's Red-winged Savannah Willet Wilson's Richness Abundance Blackbird Blackbird Sparrow Phalarope

Last Chance Creek Restored vs. Unrestored I compared species richness, focal species richness, total bird abundance, and focal species abundance at restored and untreated sites in the Last Chance Creek watershed in 2009. Along the Alkali Flat transect, eleven point count stations were within areas that have been treated while five points fell within treated areas on the Clark’s Creek transect. Seven of the restored sites at Alkali Flat were restored in 2003 with the remaining three restored in 2007. All five of the restored points at Clark’s Creek were restored in 2001. All four metrics were higher at untreated sites along the Alkali Flat transect, with species richness, focal species richness, and focal abundance significantly so (Figure 9). For Clark’s Creek, species richness, focal species richness, and focal species abundance were all higher at untreated sites while total bird abundance was higher at treated sites. Only focal species richness and abundance were significantly different between restored and un-restored points at Clark’s Creek in 2009. When all sites in the watershed were combined - including the 18 untreated points along the Lower Last Chance Creek transect - focal species richness and abundance were significantly higher at untreated sites. Species richness was higher at untreated sites while total bird abundance was higher at treated sites but these differences were not significant.

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Figure 9. Per point species richness, total bird abundance, meadow focal species richness and meadow focal species abundance at restored and un-restored point count stations at Alkali Flat, Clark’s Creek, and all sites combined in the Last Chance Creek watershed in 2009 with 95% confidence intervals.

Alkali Flat

9 8 Treated 7 Untreated 6 5 4 3 # per Point 2 1 0 Species Richness Focal Species Total Bird Focal Species Richness Abundance Abundance

Clark's Creek

10 9 Treated 8 Untreated 7 6 5 4

# per Point 3 2 1 0 Species Richness Focal Species Total Bird Focal Species Richness Abundance Abundance

Last Chance Watershed Total

8 7 Treated 6 Untreated 5 4 3 # per Point 2 1 0 Species Focal Species Total Bird Focal Species Richness Richness Abundance Abundance

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Post-breeding Meadow Use During the 2009 breeding season, we continued bird banding at the Gurnsey Creek mist- net station, the 13th consecutive year this site has been monitored (Appendix A). Single visit post-breeding mist-netting also continued at four meadows in the ARD: Hay, Swain, Spenser, and Carter. Capture rates at these meadows in 2009 were very high with between 3.21 – 5.97 captures per net hour compared to 1.15 captures per net hour, the breeding season average at Gurnsey Creek suggesting a relatively good productivity year for a number of species in the area.

Discussion Wet meadows with extensive riparian deciduous vegetation support rich and abundant breeding bird populations and are used extensively following the breeding season by the majority of upland breeding species in the Sierra. Since wet meadows represent less than 1% of National Forest land in the Sierra Nevada, and have been heavily degraded over the past century, meadow restoration and conservation should be among the highest priorities of land mangers in the Sierra Nevada. As meadows are arguably the single most important habitat for birds in the Sierra Nevada (Siegel and DeSante 1999), and birds are a cost-effective tool to help guide ecological restoration, avian monitoring and the management recommendations generated from it should be seen as a integral tool to achieving meadow restoration in the Sierra Nevada. The ARD area meadows support higher bird abundance than any other habitat type in the Lassen region we have surveyed. Only aspen habitat (see Chapter 2) has slightly higher species richness. Meadows in the greater ARD area are among the most important for meadow birds in the Sierra Nevada. Yellow Warbler, a California Bird Species of special concern, reaches its greatest reported density in the state here (RHJV 2004, Heath 2008). The area also harbors more Willow Flycatcher than any other similarly sized area of the Sierra Nevada as well as a breeding population of the state threatened Greater Sandhill Crane. With a wealth of mountain meadows and many in a degraded state, the Feather River watershed should be considered an ideal location to focus restoration actions to benefit these and other meadow dependent bird species. Though many of our meadows sites, especially in the ARD, support relatively diverse and abundant bird populations, it appears that many meadow sites (including a number we surveyed) could benefit from some additional restoration actions. For many of the sites (Robber’s Creek, Gurnsey Creek, Soldier Meadow), removal of encroaching conifers and

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

planting of willows could ensure the long-term health of these sites. Both Humbug Valley and Yellow Creek have sections of stream channel that have been isolated from their floodplains and may benefit from more significant restoration actions that restore a wet meadow condition. An increase in riparian deciduous vegetation (e.g. Salix, Populus, and Alnus spp.) at many of these sites would greatly enhance their value to meadow birds (e.g. Soldier Meadow, Last Chance Creek restored sites). There is currently little habitat value for wet meadow bird species within the Yellow Creek proposed project area. In fact, the site had the lowest avian indices of any meadow site we surveyed in 2009. In contrast, the 2 kilometers of meadow upstream from the project area support a diverse and abundant meadow bird community, including recent detections of Swainson’s Thrush and Willow Flycatcher – the two rarest meadow birds in the Sierra Nevada. Additionally, this area supports an abundant population of Yellow Warbler, a California Bird Species of Special Concern (Shuford and Gardali 2008). On Humbug Creek, 1 kilometer across the valley from the project area, there are approximately eight Willow Flycatcher territories as well as a large number of Yellow Warbler territories. Restoring Yellow Creek within the proposed project area to a wet meadow with a substantial willow component is likely to have substantial benefits to all of these meadow species of conservation interest as well as a host of other meadow dependent focal species. Unlike Yellow Creek, unrestored areas within the Last Chance Creek watershed do support populations of several meadow focal species, especially Song Sparrow and Yellow Warbler. Interestingly, we found that most avian metrics were higher at unrestored sites than restored sites in the watershed in 2009. The higher total bird abundance at restored sites is primarily due to Red-winged Blackbird being 28 time more abundant at restored sites, the species that has clearly benefited the most from restoration actions thus far. Since we do not have pre-treatment data for the areas that have been restored, it is difficult to determine how restoration has affected the rest of the avian community at these sites. However, with some of the lowest avian indices of any meadow sites we surveyed in 2009 and the fact that restored sites have lower indices than unrestored sites, it appears that additional restoration actions (e.g. willow planting) should be considered at restored sites to improve habitat for wet meadow dependent birds. Where appropriate conditions exist to support riparian deciduous shrubs and trees, creating dense clumps of these plants should improve habitat for meadow birds. Existing willow clumps

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009 within the watershed that support Yellow Warbler and Song Sparrow could be used as a template for creating suitable habitat in restored meadow areas. Alkali Flat sites 1-4 and Clark’s Creek sites 10 and 11 had the highest density of these two species on these two transects. Additional considerations during the design phase of restoration projects may also help improve habitat for meadow birds in the first 10 years after restoration. The Pine Creek Valley grassland is a distinctly different meadow than most of the sites we have surveyed. Indeed it is more of a wetland with ponded water in many years well into June with an undefined stream channel. Thus, the habitat is more suitable for bird species such as waterfowl, shorebirds, and Sandhill Crane. We documented relatively large numbers of both Wilson’s Phalarope and Willet at this site, both of which we believe breed here based on timing of their occupancy and behaviors. Additionally, a pair of Sandhill Crane was observed on both visits within and outside of the grazing exclosure. A complete list of species and their breeding status is presented in Appendix B. In 2009 the majority of the wetland area we surveyed in Pine Creek was inundated with water and therefore not actively being grazed by cattle. Thus, the differences in habitat inside and outside of the grazing exclosure did not appear great. However, we did find that Wilson’s Phalarope, Savannah Sparrow, and Red-winged Blackbirds were all substantially more abundant inside of the exclosure while Willet and Brewer’s Blackbird were more abundant outside of the exclosure. The Willets were primarily associated with the small hummocks that provided upland islands within the flooded wetland. This feature was unique to the area outside of the exclosure and may explain why the majority of Willet were found outside of the exclosure and species richness was higher here. A priority for meadow bird conservation in the Feather River watershed should be protecting and enhancing the largest wet meadows, especially for Sandhill Crane, Willow Flycatcher, and Yellow Warbler. However, our results also show that species such as Lincoln’s Sparrow, Wilson’s Warbler, and Warbling Vireo are much more abundant in smaller and higher elevation meadows, such as Carter. Several other higher elevation meadow sites such as Robber’s Creek, Hay Meadow, and Spenser Meadow (where we have conducted post-breeding banding), also support breeding Lincoln’s Sparrow. Thus, we recommend managing the larger meadow complexes at lower elevations (3500 – 5500 feet) for species such as Sandhill Crane, Willow Flycatcher, and Yellow Warbler (Childs Meadow, Battle Creek Meadow, Deer Creek Meadow, Humbug Valley, West Shore Lake Almanor) while also protecting and, where

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

necessary, enhancing higher elevation sites to support species such as Lincoln’s Sparrow and Wilson’s Warbler as well as provide critical post-breeding habitat for the majority of migratory birds that breed in the Sierra Nevada. Additionally, wetland habitats which generally support far lower abundance and diversity of meadow birds are important as they provide unique habitat for uncommon species such as Sandhill Crane, shorebirds, and waterfowl.

Conclusions With the loss and degradation of riparian meadow habitat and it disproportionate importance to birds, restoration and prudent management of meadows in the Feather River watershed should be among the highest priorities of land mangers here. Increasing the function and resiliency of wet willow-filled meadows should result in improved meadow bird habitat; however, active measures such as willow planting is likely necessary to ensure habitat is provided sooner rather than later. Meadow restoration in the Feather River watershed requires partnerships between the U.S. Forest Service, local government agencies (e.g. Feather River Coordinated Resource Management Group.), and non-profit organizations (e.g. The Nature Conservancy, Feather River Land Trust, PRBO Conservation Science). Working together these groups have the potential to dramatically increase the value of meadow habitats for birds in this region.

Acknowledgements Funding for our meadow bird project is provided through Lassen National Forest wildlife monitoring funds and a grant from the Resources Legacy Family Foundation. I wish to thank Colin Dillingham and David Arsenault for their many hours of volunteering to collect all of the bird data for the three Last Chance Creek transects. Additionally I would like to thank Tom Frolli, Bobette Jones, Tom Rickman, and Mark Williams from the Lassen National forest and Leslie Mink, Kara Rockett, and Jim Wilcox of the Feather River Coordinated Resource Management Group for their assistance and support of this project.

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

Literature Cited

Burnett, R. D., and D. L. Humple. 2003. Songbird monitoring in the Lassen National Forest: Results from the 2002 field season with summaries of 6 years of data (1997-2002). PRBO report to the U.S. Forest Service.

Burnett, R.D., D.L. Humple, T. Gardali, and M. Rogner. 2005. Avian Monitoring in the Lassen National Forest. 2004 Annual Report. PRBO report to the U.S. Forest Service.

Chase, M.K. and G.R. Geupel. 2005. The use of avian focal species for conservation planning in California. In Proceedings of the 3rd International Partners in Flight Conference. USDA Forest Service Gen. Tech. Rep. PSW-GTR-191.

Heath, S.K. 2008. Yellow Warbler (Dendroica petechia) In Shuford, W.D. & T. Gardali (eds.), California Bird Species of Special Concern. Studies of Western Birds 1. Western Field Ornithologists, Camarillo, CA and California Department of Fish and Game, Sacramento.

Humple, D.L. and R.D. Burnett 2004. Songbird monitoring in Meadow and Shrub habitats within the Lassen National Forest: Results from the 2003 Field Season. A PRBO progress report to the USDA Forest Service. PRBO Contribution # 1173.

Muir, J. 1911. My first summer in the Sierra. The Riverside Press, Cambridge, MA.

Ralph, C.J., Droege, S., Sauer, J.R., 1995. Managing and monitoring birds using point counts: standards and applications. In: C. J. Ralph, J. R. Sauer and S. Droege (Eds.), Monitoring bird populations by point counts. USDA Forest Service, General Technical Report PSW-GTR 149, 161-169.

Reynolds, R.T., J.M. Scott, and R.A. Nussbaum. 1980. A variable circular plot method for estimating bird numbers. Condor 82:309:313.

RHJV (Riparian Habitat Joint Venture). 2004. Version 2.0. The riparian bird conservation plan: a strategy for reversing the decline of riparian associated birds in California. California Partners in Flight. http://www.prbo.org/calpif/pdfs/riparian.v2.pdf.

Shuford, W.D., Gardali, T. (Eds.), 2008. California Bird Species of Special Concern. Studies of Western Birds No. 1. Western Field Ornithologists, Camarillo, CA and California Department of Fish and Game, Sacramento.

Siegel, R.B. and D.F. DeSante. 1999. Version 1.0 The draft avian conservation plan for the Sierra Nevada Bioregion: conservation priorities and strategies for safeguarding Sierra bird populations.

SNEP (Sierra Nevada Ecosystem Project) 1996. Sierra Nevada Ecosystems. Volume 1, chapter 1. Regents of the University of California. http://ceres.ca.gov/snep/pubs/web/PDF/v1_ch01.pdf

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

APPENDIX A. Summary of 2009 meadow mist-netting in the Almanor Ranger District with dates, net hours, captures, and capture rates.

Site Date Net Captures Captures/ Hours net hour Gurnsey Creek 5/20/2009 45 50 1.11 Gurnsey Creek 5/30/2009 40 49 1.23 Gurnsey Creek 6/9/2009 45 37 0.82 Gurnsey Creek 6/20/2009 43.92 52 1.18 Gurnsey Creek 6/27/2009 44.5 63 1.42 Gurnsey Creek 7/9/2009 43.5 78 1.79 Gurnsey Creek 7/17/2009 45 62 1.38 Gurnsey Creek 7/29/2009 45 33 0.73 Gurnsey Creek 8/5/2009 45 58 1.29 Gurnsey Creek 8/17/2009 45 21 0.47 Gurnsey Creek Total 441.92 503 1.14 (Summer) Gurnsey Creek 8/24/2009 44.5 35 0.79 Gurnsey Creek 9/1/2009 45 31 0.69 Gurnsey Creek 9/8/2009 45 27 0.60 Gurnsey Creek 9/15/2009 45 30 0.67 Gurnsey Creek 9/22/2009 45 64 1.42 Gurnsey Creek 9/28/2009 42 123 2.93 Gurnsey Creek Total (Fall) 266.5 310 1.16 Hay Meadow 7/30/2009 36 215 5.97 Swain Meadow 7/31/2009 36 209 5.81 Carter Meadow 8/3/2009 33 166 5.03 Spenser Meadow 8/4/2009 34 109 3.21

Chapter 3. Mountain Meadows PRBO Avian Monitoring in the Lassen National Forests - 2009

APPENDIX B. Breeding status of all bird species detected during two visits to the Pine Creek Valley wetland in 2009. Breeding status codes: 1 = confirmed breeder, 2 = likely breeder, 3 = no suitable nesting habitat within the wetland for this species probably just foraging here.

Common Name Scientific Name Breeding Status American Robin Turdus migratorius 3 Barn Swallow Hirundo rustica 1 Brewer's Blackbird Euphagus cyanocephalus 2 Brewer's Sparrow Spizella breweri 2 Cliff Swallow Petrochelidon pyrrhonota 1 Common Raven Corvus corax 3 Horned Lark Eremophila alpestris 2 Killdeer Charadrius vociferus 2 Mallard Anus mallardi 2 Mountain Bluebird Sialia currucoides 2 Mourning Dove Zenaida macroura 2 Northern Pintail Anas aculta 2 Northern Shoveler Anas clypeata 2 Red-winged Blackbird Agelaius phoeniceus 1 Sandhill Crane Grus canadensis 2 Savannah Sparrow Passerculus sandwichensis 2 Spotted Sandpiper Actitis macularia 2 Vesper Sparrow Pooecetes gramineus 2 Western Meadowlark Sturnella neglecta 2 Willet Catoptrophorus semipalmatus 2 Wilson's Phalarope Phalaropus tricolor 1 Yellow-headed Blackbird Xanthocephalus xanthocephalus 2