https://cpw.cvlcollections.org/files/original/1a6449ad7bae5a0bcf05acf0a41a425f.pdf 17d77e5aeef86879ec6f61d15d168053 PDF Text Text Colorado Division of Parks and Wildlife September 2013-September 2014 WILDLIFE RESEARCH REPORT State of: Cost Center: Work Package: Task No.: Colorado 3420 0660 N/A Federal Aid Project No. N/A : : : : Division of Parks and Wildlife Avian Research Greater Sage-grouse Conservation Assessment of Greater Sage-grouse Response to Pinyon-Juniper Removal in the ParachutePiceance-Roan Population of Northwestern Colorado Period Covered: September 1, 2013 – August 31, 2014 Author: B. L. Walker Personnel: B. Holmes, B. Petch, T. Knowles, B. deVergie All information in this report is preliminary and subject to further evaluation. Information MAY NOT BE PUBLISHED OR QUOTED without permission of the author. Manipulation of these data beyond that contained in this report is discouraged. ABSTRACT Greater sage-grouse (Centrocercus urophasianus) in the Parachute-Piceance-Roan (PPR) region of western Colorado face at least two major potential stressors: projected habitat loss from energy development and a long-term decline in habitat suitability associated with pinyon-juniper (PJ) encroachment. PJ removal may be a useful mitigation tool to offset potential habitat losses associated with energy development. Although PJ removal is commonly used to improve habitat for greater sagegrouse, no studies to date have quantified the timing or magnitude of how birds respond to treatments. Since 2008, Colorado Parks and Wildlife (CPW) has cooperated with industry and landowner partners to investigate the effectiveness of PJ removal for restoring sage-grouse habitat in the PPR. In fall 2008, I established nine “survey” study plots, arranged in three groups of three, with each group consisting of a sagebrush control plot, an untreated PJ control plot, and a PJ treatment plot. Treatments were completed on the three treatment plots in 2010 and 2011. Pellet surveys over six summers (20092014) indicated that the mean proportion of sample units containing pellets was consistently highest on sagebrush control plots (range 0.197-0.449 across years), consistently lowest on plots with encroaching PJ (range 0.007-0.076), and increased starting 1-2 years after treatment, but response was variable among treatment plots. Twelve transect plots were established in fall 2010 and two more were added in summer 2011. All 14 transect plots were surveyed for pellets in summer from 2011-2014. Transect data indicated low mean pellet densities on the four PJ-Control plots over three years (range across years = 0.00-0.58 pellet piles/km) and on PJ-Treatment plots in the one year prior to treatment (mean = 0.03 pellet piles/km). Estimates of mean pellet density were substantially higher on four Sagebrush-Control transect plots over three years (range across years = 11.10 - 27.14 piles/km) and on one transect plot 4-6 years after treatment (Lower Barnes; range across years = 2.89 - 25.71 piles/km). There has been no increase in mean pellet density on four treated transect plots within three years after PJ removal (range across years = 0.00 - 1.04 pellet piles/km). However, estimates of proportion of sample units with pellets (from survey plots) and of pellet density (from transect plots) also varied 1 �substantially among Sagebrush-Control plots within years and among years within plots, which suggests there is substantial baseline variation in pellets present, over and above variation in detection due to observer ability. We completed double-observer sampling on survey plots in 2013 and 2014 to estimate sample unit-level detectability, and we completed distance sampling on transect plots to generate distance-detection curves for transects. We established and conducted pre-treatment surveys on two additional transect plots in summer 2014 (Lower Galloway and Lower Ryan Gulch) in anticipation of treatments by WPX this fall. 2 �WILDLIFE RESEARCH REPORT ASSESSMENT OF GREATER SAGE-GROUSE RESPONSE TO PINYON-JUNIPER REMOVAL IN THE PARACHUTE-PICEANCE-ROAN POPULATION OF NORTHWESTERN COLORADO BRETT L. WALKER PROJECT OBJECTIVES The objective of this study is to measure short-term (< 5 year) responses of greater sage-grouse to experimental PJ removal using changes in pellet occupancy in a before-after control-treatment framework. SEGMENT OBJECTIVES Objectives of this study from 1 Sept 2013 through 31 August 2014 were to: 1. Conduct pellet surveys on 9 survey plots. 2. Conduct repeat surveys on 9 survey plots to estimate detectability at the sample unit level. 3. Conduct pellet transects on 14 transect plots. 4. Conduct distance sampling for pellets on a subset 4 transect plots. 5. Summarize preliminary results of pellet surveys and transects from 2009-2014. INTRODUCTION Large-scale changes to sagebrush ecosystems and historical population declines (Schroeder et al. 2004) have raised concern about the status and conservation of greater sage-grouse (Centrocercus urophasianus) and contributed to the recent listing of the species as warranted but precluded under the Endangered Species Act (DOI 2010). The Parachute-Piceance-Roan (PPR) region holds one of seven distinct geographic populations of greater sage-grouse in northwestern Colorado. Greater sage-grouse in the PPR are of conservation concern due to a long-term reduction in habitat suitability caused by encroachment of pinyon pine (Pinus monophylla) and juniper (Juniperus scopularum and Juniperus utahensis) into sagebrush and potential impacts from rapidly increasing energy development. Removal of pinyon-juniper (PJ) from areas with an existing sagebrush understory may help restore sage-grouse habitat and offset future potential habitat losses from energy development. Pinyonjuniper encroachment into sagebrush over the last 150 years has been identified as a threat to the species’ habitat in the PPR, in Colorado and range-wide (CGSSC 2008). Encroachment is thought to be caused by fire suppression, reduced fire frequency due to removal of residual grass via livestock grazing, and a window of climatic conditions suitable for PJ establishment during the late 1800s and early 1990s (Miller and Rose 1999). Pinyon-juniper removal has been widely implemented in Colorado and range-wide (CGSSC 2008). However, sage-grouse responses to PJ removal remain poorly studied (Commons et al. 1999), and the timing and magnitude of greater sage-grouse responses following treatment is unknown. For this reason, it is difficult to judge whether PJ removal can effectively increase available habitat and offset impacts from energy development. Since 2008, the Colorado Division of Wildlife, now Colorado Parks and Wildlife (CPW), and industry and landowner partners have been cooperating on research to assess the value of removing encroaching PJ as a mitigation strategy in the PPR. The main objective of this study is to measure shortterm (<5 years) responses of greater sage-grouse to experimental PJ removal using changes in pellet occupancy in a before-after control-treatment framework. This progress report summarizes preliminary results from summer pellet surveys for the period June 2009 - August 2014. 3 �STUDY AREA Study plots are within or immediately adjacent to the current occupied range of greater sage-grouse in the PPR (Fig. 1). Birds in the PPR population inhabit the tops of ridges and plateaus dominated by mountain big sagebrush (Artemisia tridentata vaseyana) and a mixture of sagebrush and “mountain shrubs” (e.g., serviceberry, Amelanchier spp.; Gambel oak, Quercus gambelii, snowberry, Symphoricarpus sp.; antelope bitterbrush, Purshia tridentata, mountain mahogany, Cercocarpus sp., etc.). These areas are typically interspersed with patches of aspen (Populus tremuloides) and Douglas-fir (Pseudotsuga menziesii). Sagebrush and mixed sagebrush-mountain shrub habitats at higher elevation give way to PJ woodland on lower-elevation ridges that largely precludes use by sage-grouse. Our study plots are situated along the ecotone where PJ is encroaching upslope into sagebrush and sagebrushmountain shrub habitat. METHODS Plot Selection I used vegetation, topography, marked bird locations, aerial photography, and on-site visits to identify nine study plots in 2008, 14 additional study plots in 2010 and 2011, and two additional plots in 2014 (Fig. 1). Study plots were selected based on: (1) density of PJ; (2) shrub composition, density, and height; (3) topography; (4) proximity to areas of known use by greater sage-grouse; and (5) proximity to, and likelihood of, energy development within five years. All plots had a sagebrush-dominated shrub layer, typically intermixed with mountain shrubs, and topography similar to habitats used by sage-grouse in the PPR from 2006-2010 (Apa 2010, Walker 2010). The southeast portion of the PPR population is experiencing intensive energy development, but there is currently no development within the study plots and limited development nearby. Two of the plots added in 2011 (Upper and Lower Bar D) were treated by the Bureau of Land Management in January 2011 and were added opportunistically in our study. An additional plot (Lower Barnes) added in 2011 was treated by BLM in 2007-2008 and is being surveyed as a longer-term post-treatment plot for comparison. Assessing Response to Pinyon-Juniper Removal I am using a before-after, control-treatment design to compare changes in sage-grouse pellet occupancy among control and removal plots before and after encroaching PJ is removed. Caution must be exercised in interpreting results because estimates of pellet occupancy only give an index of frequency of use during a defined survey period, rather than a measure of abundance, density, habitat quality, or habitat selection (contra Dahlgren et al. 2006). I have three levels of treatment: 1) “PJ-Treatment” plots where encroaching PJ is removed, 2) “PJ-Control” plots where encroaching PJ is not removed, and 3) “Sagebrush-Control” plots with suitable sagebrush habitat and no PJ. Data from PJ-Treatment plots are used to measure changes in pellet occupancy before and after PJ removal. PJ-Control plots allow us to measure background changes and variation in pellet occupancy in areas with encroaching PJ in the absence of treatment. Sagebrush-Control plots allow us to estimate background changes and variation in pellet occupancy in habitats already suitable for sage-grouse. Most plots were surveyed for one to three years prior to PJ removal and will be surveyed for two to five years following removal. I established three study plots per treatment in fall 2008 for a total of nine original “survey” plots. I established 12 additional transect-based study plots in fall 2010 and two more transect-based plots in summer 2011 (Figs. 2-4), for a total of 23 study plots (nine survey, 14 transect). Summer Pellet Surveys and Transects 4 �I obtained an index of frequency of sage-grouse use of plots by surveying for pellets during the summer and estimating pellet occupancy. I used two different sampling techniques for pellet surveys. The first technique involves surveying a systematic random sample of 30 x 30 m sample units on each “survey” plot. The second technique involves surveying for pellets within 1.5 m on either side of linear transects spaced 50 m apart that ran the length of each “transect” study plot. With both sampling methods, field crews searched for, counted, and removed pellets from each sample unit (or transect line) within the plot once per year in July-August. For all pellets, field crews recorded their condition and appearance (crumbly-bleached vs. hard-dry, vs. fresh-wet) to estimate age and used composition to estimate when during the year they were deposited. Field crews identified those containing intact insect parts and flower heads as “summer” pellets (April-October) and those containing only digested sagebrush leaves as “winter” pellets (November-March) (Wallestad et al. 1975). Field crews recorded single pellets, pellet piles (i.e., day or night roost piles), and cecal droppings separately. Observers recorded pellets or groups of pellets within 10 cm of each other as one pile, with the constraint that pellets or groups of pellets > 10 cm apart could not be counted as the same pile. I opted to sample each plot once per year in July-August such that the “survey period” (i.e., the period during which birds can deposit pellets) was 12 months. Field crews marked all sample unit centers and transect lines with aluminum tags, high-visibility stakes and high-visibility flagging to ensure consistency in sampling locations across years. On survey plots, each observer carefully and thoroughly surveyed sample units by slowly walking 10 parallel 30-m lines spaced 3 m apart. On transect plots, observers survey for pellets by walking flagged transect lines and searching within 1.5 m on either side of the line. Observers recorded anecdotal evidence of occupancy while surveying (e.g., clockers, nests and eggs, feathers, birds, etc.). These two survey methods for pellets have the following assumptions: 1) all pellets can be correctly identified to species; 2) all pellets can be correctly distinguished as either a chick or adult pellet by size; 3) all pellets deposited during the survey period (during the previous year) can be correctly distinguished from pellets deposited prior to the survey period by condition and appearance; 4) all pellets can be correctly distinguished by season (“winter” vs. “summer”) by pellet composition; 5) surveying does not influence whether or not pellets are present in sampled units (or along transects). To address assumption 1, I trained observers to distinguish dusky grouse from sage-grouse pellets prior to surveys. Adult pellets of the two species can be distinguished by composition and smell in any season. Adult-sized sage-grouse typically consume 13-39% sagebrush throughout the spring and summer and >99% sagebrush in winter (Wallestad et al. 1975, Schroeder et al. 1999). For this reason, pellets of adult sagegrouse contain sagebrush year-round, and unlike dusky grouse, consistently smell like sage, even after a year in the field. To address assumption 2, I trained crews to distinguish adult from chick pellets by length and diameter Quantitative analyses will only include data on adult-size pellets because it may not be possible to distinguish pellets of dusky grouse vs. sage-grouse chicks due to overlap in chick diets (both species consume primarily insects and forbs as chicks; Zwickel 1992, Drut et al. 1994). To address assumption 3, crews differentiated pellets in the field based on condition (bleached and crumbly vs. hard and dry vs. fresh and green/moist). I am also testing how pellet condition changes with age by placing piles of fresh test pellets within representative sagebrush habitat in the field and photographing changes in condition over time. I will test assumption 4 by testing how often observers correctly assess composition and season for pellets collected from marked birds in different seasons. Assumption 5 may be violated if surveyors flush birds that then land within another sample unit or along a transect line later surveyed. However, violation of this assumption is unlikely to meaningfully influence analyses because the number of pellets birds could deposit before the unit or transect gets surveyed (on the order of minutes or hours) is miniscule compared to the 12-month survey period. Pellet Detectability 5 �Detectability of sage-grouse pellets is typically low and may vary among observers, with pellet condition or appearance, and with distance from observer (Dahlgren et al. 2006). In 2009-2012, I estimated variation in detectability of individual pellets/pellet piles among observers by having each observer survey eight test sample units in which I placed piles of fresh pellets of various sizes at random directions and distances within the sample unit from the sample unit center. Pellets were also placed at random distances within 1.5 m along two 400-m long test transects in 2011 and 2012. Field crews also conducted repeat surveys of all survey plots on the same dates in 2013 and 2014 to allow estimation of detectability at the sample-unit level using unreconciled double-observer methods (Riddle et al. 2010), and conducted distance sampling on all Sagebrush-Control transect plots in 2014 to allow estimation of pellet distance-detection curves for transect data. Pinyon-Juniper Removal All treatments were done by contractors using either a Bobcat with a Fecon head or a Hydro-axe. Contractors were instructed to remove only pinyon-juniper and to avoid removing sagebrush or mountain shrubs. A partial treatment was done on the Black Sulphur plot in August 2009 and completed in July 2010, the Upper Galloway plot was treated in November 2010, and the Ryan Gulch plot was treated in August 2011. Among transect plots, Upper and Lower Bar D plots were treated by BLM in January 2011, and three plots (Cottonwood, Magnolia South, and Lower Wagonroad) were treated in August-November 2011. Two additional plots added in summer 2014 (Lower Ryan Gulch and Lower Galloway) are adjacent to two existing study plots (Upper Galloway and Upper Ryan Gulch) and scheduled for treatment by WPX Energy (in conjunction with CPW and BLM) in fall 2014. RESULTS AND DISCUSSION Pellet Surveys and Transects Pellet survey data from 2009-2014 indicated substantially higher mean seasonal and year-round pellet detections on Sagebrush-Control survey plots than on PJ-Control plots or on PJ-Treatment plots prior to treatment (Table 1). Year-round pellet detections increased on the Upper Galloway and Ryan Gulch plots increased and have remained slightly higher following treatment on both plots since treatment (Fig. 2, Tables 1). However, there has been no increase in year-round pellets detected on the Black Sulphur plot within four years following treatment. Observers conducted repeat surveys of all 9 survey plots on the same dates in 2013 and 2014 to allow us to estimate detectability of pellets at the sample unit level. Preliminary comparison of resulting estimates suggests there is substantial variation in observer ability to detect pellets within 30 x 30 m sample units in both years (Table 2). Field crews conducted one round of pellet surveys on each of 14 transect plots in July-August in each year from 2011-2014 (Table 3, Fig. 4). No transect plots showed an increase in the no. pellets counted per km of transect within two years following treatment, but the mean increased within 3 years (Fig. 5). However, this increase was driven entirely by an increase on a single plot (Upper Bar D; Fig. 4). The no. of pellets counted per km of transect was highly variable on the Lower Barnes plot (treated by BLM in 2007-2008), but generally comparable to Sagebrush-Control plots. No pellets were counted on pre-treatment transects on the two new plots (Lower Galloway and Lower Ryan Gulch) established in summer 2014. Field crews collected distance sampling data on all Sagebrush-Control transect plots in 2014 to generate pellet distance-detection curves for transect plots. Crews recorded 403 detections, and all pellets detected were within 3.0 m. These data will be analyzed following additional data collection in 2015. 6 �Taken together, summer pellet data from the pre-treatment phase of the project indicated substantially greater pellet detections on Sagebrush-Control plots than on either PJ-Control plots or PJTreatment plots prior to treatment. There has not been a consistent, immediate, or dramatic increase in sage-grouse pellet detections in treated areas, suggesting that if there is a response by sage-grouse to such habitat treatments, it may take several years for individuals to colonize and begin using treated areas. Alternatively, sites selected for removals may still represent marginal habitat, and pellet detections may never increase to levels comparable to Sagebrush-Control plots. The number of pellets found on Sagebrush-Control plots has also been highly variable across years, suggesting there substantial natural variation in the number of pellets deposited (over and above that variation introduced by observer bias). Even so, increases in the number of pellet detections on 3 of 8 treated plots within 4 years of treatment, combined with consistently low detections on PJ-Control plots during that same time, suggests that greater sage-grouse do show a positive response to PJ removal in some areas. Current post-treatment data are insufficient to draw conclusions about long-term responses of greater sage-grouse to PJ removal. We anticipate conducting one additional year of pellet surveys (through summer 2015) to ensure we document grouse response for at least 4-5 years post-treatment. We may continue pellet surveys beyond 2015 if interest and funding are available, particularly if there is interest in treating PJ-Control study plots. LITERATURE CITED Apa, A. D. 2010. Seasonal habitat use, movements, genetics, and vital rates in the Parachute-PiceanceRoan Population of greater sage-grouse. Unpublished progress report. Colorado Division of Wildlife. Fort Collins, USA. Becker, E. F. 1991. A terrestrial furbearer estimator based on probability sampling. Journal of Wildlife Management 55: 730-737. Becker, E. F., Golden, H. N., and Gardner, C. L. 2004. Using probability sampling of animal tracks in snow to estimate population size. In Thompson, W. L., ed., Sampling rare or elusive species: concepts and techniques for estimating population parameters. Island Press, Washington, D. C., USA, pp. 248-270. Becker, E. F., M. A. Spindler, and T. O. Osborne. 1998. A population estimator based on network sampling of tracks in the snow. Journal of Wildlife Management 62:968-977. Canfield, R. H. 1941. Application of the line interception method in sampling range vegetation. Journal of Forestry 39:388–394. Colorado Greater Sage-Grouse Steering Committee (CGSSC). 2008. Colorado greater sage-grouse conservation plan. Colorado Division of Wildlife, Denver, USA. Commons, M. L., R. K. Baydack, and C. E. Braun. 1999. Sage grouse response to pinyon-juniper management. Pages 238-239 in S. B. Monsen and R. Stevens, compilers. Proceedings: ecology and management of pinyon-juniper communities. RMRS-P-9. United States Department of Agriculture, Forest Service, Fort Collins, Colo. USA. Dahlgren, D. K., R. Chi, and T. A. Messmer. 2006. Greater sage-grouse response to sagebrush management in Utah. Wildlife Society Bulletin 34:975-985. Department of the Interior (DOI). 2010. 12-month finding for petitions to list the greater sage-grouse as threatened or endangered. Federal Register 75(55): 13910-14014. Drut, M. S., W. H. Pyle, and J. A. Crawford. 1994. Technical note: Diets and food selection of Sage Grouse chicks in Oregon. Journal of Range Management 47:90-93. Miller, R. F. and J. A. Rose.1999. Fire history and western juniper encroachment in sagebrush steppe. Journal of Range Management 52:550-559. 7 �Schroeder, M. A., C. L. Aldridge, A. D. Apa, J. R. Bohne, C. E. Braun, S. D. Bunnell, J. W. Connelly, P. A. Deibert, S. C. Gardner, M. A. Hilliard, G. D. Kobriger, C. W. Mccarthy. 2004. Distribution of Sage-grouse in North America. Condor 106:363-376. Schroeder, M. A., J. R. Young, and C. E. Braun. 1999. Sage-grouse (Centrocercus urophasianus). Account 425 in A. Poole and F. Gill, editors. The birds of North America. The Academy of Natural Sciences, Philadelphia, Pa. USA. Walker, B. L. 2010. Greater sage-grouse research in the Parachute-Piceance-Roan region of western Colorado: multi-scale habitat selection and seasonal habitat mapping. Unpublished interim progress report. Colorado Division of Wildlife. Fort Collins, USA. Wallestad, R., J. G. Peterson, and R. L. Eng. 1975. Foods of adult sage grouse in central Montana. Journal of Wildlife Management 39:628-630. Zwickel, F. C. 1992. Blue Grouse (Dendragapus obscurus). Account 15 in A. Poole, P. Stettenheim, and F. Gill, editors. The birds of North America. The Academy of Natural Sciences, Philadelphia, Pa. USA. 8 �Table 1. Preliminary estimates of proportion of sample units ± SE containing greater sage-grouse pellets (from any season) on survey plots in the ParachutePiceance-Roan population of western Colorado, USA from 2009-2014. Values presented do not account for sample-unit level variation in pellet detectability. PJ - Treatment Plotsa PJ - Control (No Treatment) Plots Sagebrush - Control Plots 1-Upper 2-Black 3-Ryan MEAN 1-Dry 3-Stake MEAN 1-Dry 2-Canyon 3-Black MEAN Galloway Sulphur Gulch ± SE Ryan 2-Eureka Springs ± SE Gulch Creek Cabin ± SE b b b c Year n = 49 n = 38 n = 48 N=3 n = 35 n = 50 n = 38 N=3 n = 54 n = 41 n = 42 N=3 d 2009 0.082 0.000 0.146 0.076 0.000 0.040 0.105 0.048 0.444 0.293 0.452 0.397 ± 0.039 ± 0.000 ± 0.051 ± 0.042 ± 0.000 ± 0.033 ± 0.05 ± 0.031 ± 0.068 ± 0.071 ± 0.077 ± 0.052 2010 0.000 0.104 0.052 0.029 0.040 0.026 0.032 0.721 0.293 0.333 0.449 0.026 ± 0.000 ± 0.026 ± 0.044 ± 0.052 ± 0.028 ± 0.028 ± 0.026 ± 0.004 ± 0.068 ± 0.071 ± 0.073 ± 0.136 2011 0.063 0.000 0.020 0.000 0.007 0.349 0.171 0.071 0.197 0.082 0.000 0.041 ± 0.035 ± 0.041 ± 0.000 ± 0.020 ± 0.000 ± 0.007 ± 0.073 ± 0.059 ± 0.040 ± 0.081 ± 0.039 ± 0.000 2012 0.029 0.040 0.000 0.023 0.605 0.341 0.262 0.403 0.245 0.026 0.188 0.153 ± 0.028 ± 0.028 ± 0.000 ± 0.012 ± 0.075 ± 0.074 ± 0.068 ± 0.104 ± 0.061 ± 0.026 ± 0.056 ± 0.065 2013 0.000 0.100 0.000 0.033 0.605 0.220 0.381 0.402 0.082 0.000 0.188 0.090 ± 0.000 ± 0.042 ± 0.000 ± 0.033 ± 0.075 ± 0.065 ± 0.075 ± 0.112 ± 0.039 ± 0.000 ± 0.056 ± 0.054 2014 0.000 0.000 0.026 0.009 0.535 0.146 0.381 0.354 0.082 0.000 0.333 0.138 ± 0.000 ± 0.000 ± 0.026 ± 0.009 ± 0.076 ± 0.055 ± 0.075 ± 0.113 ± 0.039 ± 0.000 ± 0.068 ± 0.100 a Values in bold represent post-treatment data. Numbers before plot names refer to set (e.g., Set 1 = Upper Galloway, Dry Ryan, Dry Gulch, etc.). b n refers to no. of 30 x 30 m units sampled within the study plot. c N refers to no. of study plots contributing to the mean. Means in bold are for post-treatment plots, otherwise values represent pre-treatment data. d p = proportion of sample units per plots in which greater sage-grouse pellets were detected. Subscripts refer to year. 9 �Table 2. Observer variation in estimates of proportion of sample units with greater sage-grouse pellets (from any season) on survey plots from repeat surveys in the Parachute-Piceance-Roan population of western Colorado, USA in 2013 and 2014. Values presented do not account for variation in sample-unit level detectability of pellets. Surveys of each sample unit were conducted by a different observer within 20-30 minutes of each other on the same date. PJ - Treatment Plots (post-treatment) PJ - Control (No Treatment) Plots Sagebrush - Control Plots 1-Upper Galloway n = 49a pBc 3-Ryan Gulch n = 48a MEAN ± SE N = 3b 0.000 ± 0.000 0.000 ± 0.000 0.188 ± 0.056 0.167 ± 0.054 0.090 ± 0.054 0.130 ± 0.067 1-Dry Ryan n = 35 3-Stake Springs n = 38 MEAN ± SE N=3 0.000 ± 0.000 0.000 ± 0.000 0.033 ± 0.033 0.013 ± 0.013 1-Dry Gulch n = 43 2-Canyon Creek n = 41 3-Black Cabin n = 42 MEAN ± SE N=3 0.220 ± 0.065 0.195 ± 0.062 0.381 ± 0.075 0.238 ± 0.066 0.402 ± 0.112 0.299 ± 0.084 0.184 0.000 0.250 0.145 0.029 0.026 0.052 0.488 ± 0.055 ± 0.000 ± 0.063 ± 0.075 ± 0.028 ± 0.026 ± 0.024 ± 0.076 pAc 0.082 0.000 0.333 0.138 0.000 0.026 0.009 0.535 ± 0.039 ± 0.000 ± 0.068 ± 0.100 ± 0.000 ± 0.026 ± 0.009 ± 0.076 a n refers to the number of sample units per study plot. b N refers to the no. of study plots contributing to the mean. c p = proportion of sample units in which greater sage-grouse pellets were detected. Subscript refers observer (A or B). 0.098 ± 0.046 0.146 ± 0.055 0.548 ± 0.077 0.381 ± 0.075 0.378 ± 0.141 0.354 ± 0.113 pBc 0.000 ± 0.000 0.000 ± 0.000 2-Eureka n = 50 2013 0.100 ± 0.042 0.040 ± 0.028 2014 0.100 ± 0.042 0.000 ± 0.000 0.605 ± 0.075 0.465 ± 0.076 pAc 0.082 ± 0.039 0.224 ± 0.06 2-Black Sulphur n = 38a 10 �Table 3. Preliminary estimates of the density of greater sage-grouse pellets (from any season) encountered on transect plots in the Parachute-Piceance-Roan population of western Colorado, USA from 2011-2014. Values presented do not account for variation in pellet detectability with distance. PJ - Treatment Plotsa PJ - Control (No Treatment) Plots Sagebrush - Control Plots Lower Upper Bar Upper WagonMagnolia Cotton- Wagon- Lower Upper Lower Magnolia WagonD Magnolia Barnes road Bar D South wood road Bar D Bar D Barnes North Sprague road Split Control Control Control Control x2011b 0.10 0.00 0.00 0.00 0.00 0.00 0.00 18.82 13.51 6.46 5.61 0.00 0.00 13.78 c X2011 0.03 ± 0.03 0.00 ± 0.00 11.10 ± 3.84 0.00 ± 0.00 x2012 X2012 2.02 0.00 0.31 0.00 46.03 7.94 31.63 22.96 0.00 0.00 0.63 25.51 0.58 ± 0.42 27.14 ± 7.97 0.75 ± 0.54 x2013 0.00 0.00 0.00 0.00 18.53 1.01 11.56 60.03 0.31 0.00 0.00 0.52 0.00 2.89 X2013 0.00 ± 0.00 22.79 ± 12.93 0.17 ± 0.11 x2014 0.00 0.00 0.10 0.00 19.41 4.22 15.31 33.16 2.14 0.00 0.00 0.10 8.96 3.91 X2014 0.00 ± 0.00 18.03 ± 5.98 2.24 ± 1.73 d km 9.80 7.52 7.64 9.58 6.36 5.88 6.44 12.52 9.80 4.68 6.80 5.92 5.88 5.88 (7.70) (13.40) a Post-treatment data are in bold. Treatments on Lower Bar D and Upper Bar D occurred in Jan 2011. Data for Lower Bar D and Upper Bar D from 2011-2014 represent ~6, 18, 30, and 42 mo post-treatment, respectively. Treatments on Lower Barnes were started by the Bureau of Land Management in summer 2007 and completed in summer 2008. Post-treatment data on Lower Barnes were collected opportunistically and are presented for comparison only. b x = no. pellet piles detected per km of transect. c X = mean no. pellet piles detected per km of transect across study plots within each treatment. Values for Lower Barnes are presented separately. The 2011 mean for Lower Bar D and Upper Bar D in 2011 represents post-treatment data and is presented separately from the 2011 mean for other PJ – Treatment plots that had not yet been treated (Magnolia South, Cottonwood, Lower Wagonroad). d Total km of transect line surveyed per plot. Portions of transects on Cottonwood and Sprague unsuitable as greater sage-grouse habitat were eliminated in 2012, values in parentheses indicate km surveyed in 2011 only. 2.86 0.27 11 �Table 4. Timeline for research on greater sage-grouse response to pinyon-juniper removal in the ParachutePiceance-Roan population, western Colorado, 2008-2015. Task Identification of plots for PJ removal Remove encroaching PJ on survey treatment plots (2009-2011) Remove encroaching PJ on transect treatment plots (2011) Remove encroaching PJ on new transect treatment plots (2014) Pellet surveys (annually) Prepare cumulative report (annually) Prepare cumulative final report 12 Initiation Summer 2008 Fall 2009 Fall 2011 Fall 2014 25 June 1 Sep 1 Aug 2015 Completion COMPLETED COMPLETED COMPLETED Fall 2014 31 Aug 30 Sep 30 Sep 2015 �Fig. 1. Map of study plot locations from 2009-2014 for the pinyon-juniper removal experiment and greater sage-grouse occupied range boundary (as of 2012) in the northern portion of the Parachute-Piceance-Roan population of western Colorado, USA. 13 �Fig. 2. Trends in the proportion of sample units detected with greater sage-grouse pellets for individual survey plots (color-coded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2009-2014. Values presented do not account for variation in sample-unit level detectability of pellets. 14 �Fig. 3. Trends in the mean proportion of sample units detected with greater sage-grouse pellets across survey plots (color-coded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2009-2014. Values presented do not account for variation in sample-unit level detectability of pellets. 15 �Fig. 4. Trends in the no. of greater sage-grouse pellets counted per km of transect for individual transect plots (color-coded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2011-2014. Values presented do not account for variation in detectability of pellets with distance from transect. 16 �Fig. 5. Trends in the mean no. of greater sage-grouse pellets counted per km of transect across transect plots within treatments (colorcoded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2011-2014. Values presented do not account for variation in detectability of pellets with distance from transect. 17 � https://cpw.cvlcollections.org/files/original/1b46ee15fe83563c564e0ded7b4dcd22.pdf afda750eace2668d43054502f50ef13e PDF Text Text Colorado Division of Parks and Wildlife September 2014-September 2015 WILDLIFE RESEARCH REPORT State of: Cost Center: Work Package: Task No.: Colorado 3420 0660 N/A Federal Aid Project No. N/A : : : : Division of Parks and Wildlife Avian Research Greater Sage-grouse Conservation Assessment of Greater Sage-grouse Response to Pinyon-Juniper Removal in the ParachutePiceance-Roan Population of Northwestern Colorado Period Covered: September 1, 2014 – August 31, 2015 Author: B. L. Walker Personnel: B. Holmes, B. Petch, T. Knowles, B. deVergie All information in this report is preliminary and subject to further evaluation. Information MAY NOT BE PUBLISHED OR QUOTED without permission of the author. Manipulation of these data beyond that contained in this report is discouraged. EXTENDED ABSTRACT Greater sage-grouse (Centrocercus urophasianus) in the Parachute-Piceance-Roan (PPR) region of western Colorado face at least two major potential stressors: projected habitat loss from energy development and a long-term decline in habitat suitability associated with pinyon-juniper (PJ) encroachment. Pinyon-juniper removal may be a useful mitigation tool to offset potential habitat losses associated with energy development. Although pinyon-juniper removal is commonly used to improve habitat for greater sage-grouse, no studies to date have quantified the timing or magnitude of how birds respond to treatments. Since 2008, Colorado Parks and Wildlife (CPW) has cooperated with industry and landowner partners to investigate the effectiveness of pinyon-juniper removal for restoring sage-grouse habitat in the PPR. In fall 2008, I established nine “survey” study plots, arranged in three groups of three, with each group consisting of a Sagebrush-Control plot, an untreated PJControl plot, and a PJ-treatment plot. Treatments were completed on three survey plots in 2010 and 2011. Pellet surveys in summer from 2009-2015 indicated that the mean proportion of sample units containing pellets was consistently highest on sagebrush control plots (range 0.197-0.449 across years), consistently lowest on plots with encroaching pinyon-juniper (range 0.007-0.048), and increased on 2 of 3 treated survey plots (Ryan Gulch and Upper Galloway) within 1-2 years after treatment. Fourteen transect plots were established in fall 2010 and summer 2011, and two were established in summer 2014. Transect plots were surveyed for pellets in summer though 2015. As expected, estimated mean pellet piles/km were low on the four PJ-Control plots for the duration of the study (range across years = 0.00-0.58 pellets/km) and on PJ-Treatment plots prior to treatment (mean = 0.03 pellet piles/km). Mean pellet piles/km were consistently higher on all four Sagebrush-Control transect plots through 2014 (range across years = 11.10 - 27.14 pellet piles/km), but declined precipitously on 3 of 4 Sagebrush-Control plots in 2015 (Magnolia Control, Upper Barnes Control, and Wagonroad Control). Pellet piles/km were also high on the Lower Barnes transect plot 4-5 years post-treatment (13.78-25.71 piles/km), but declined 6-8 years post-treatment (0.00-3.91 pellet 1 �piles/km). Mean pellet piles/km has generally remained low on treated transect plots for four years after pinyon-juniper removal (range across years = 0.00 - 2.86 pellet piles/km) with the exception of Upper Bar D in 2014 (8.96 pellet piles/km). Estimates of proportion of sample units with pellets (from survey plots) and of pellet piles/km (from transect plots) also varied substantially among SagebrushControl plots within years and among years within plots, which suggests there is substantial variation in pellets deposited within suitable habitat (i.e., over and above variation in counts due to observer bias). We completed double-observer sampling on survey plots in 2013, 2014, and 2015 to estimate sample unit-level detectability, and we completed distance sampling on transect plots in 2014 and 2015 to generate distance-detection curves, and those analyses are in progress. We established and conducted pre- and post-treatment surveys on two additional transect plots (Lower Galloway and Lower Ryan Gulch) in summer 2014 and 2015. To date, response to pinyon-juniper removal has been inconsistent, with pellet counts increasing on only two of eight plots within 4-5 years post-treatment. However, a recent experimental treatment suggests that sage-grouse may respond more strongly to combined pinyon-juniper and serviceberry removal. We are developing a proposal to expand the current pinyon-juniper removal project to include serviceberry treatments on existing study plots starting in fall 2017. 2 �COLORADO PARKS AND WILDLIFE RESEARCH REPORT ASSESSMENT OF GREATER SAGE-GROUSE RESPONSE TO PINYON-JUNIPER REMOVAL IN THE PARACHUTE-PICEANCE-ROAN POPULATION OF NORTHWESTERN COLORADO BRETT L. WALKER INTRODUCTION Large-scale changes to sagebrush ecosystems and historical population declines (Schroeder et al. 2004) have raised concern about the status and conservation of greater sage-grouse (Centrocercus urophasianus) and contributed to the recent listing of the species as warranted but precluded under the Endangered Species Act (DOI 2010). The Parachute-Piceance-Roan (PPR) region holds one of seven distinct geographic populations of greater sage-grouse in northwestern Colorado. Greater sage-grouse in the PPR are of conservation concern due to a long-term reduction in habitat suitability caused by encroachment of pinyon pine (Pinus monophylla) and juniper (Juniperus scopularum and Juniperus utahensis) into sagebrush and potential impacts from rapidly increasing energy development. Removal of pinyon-juniper from areas with an existing sagebrush understory may help restore sage-grouse habitat and offset future potential habitat losses from energy development. Pinyon-juniper encroachment into sagebrush over the last 150 years has been identified as a threat to the species’ habitat in the PPR, in Colorado and range-wide (CGSSC 2008). Encroachment is thought to be caused by fire suppression, reduced fire frequency due to removal of residual grass via livestock grazing, and a window of climatic conditions suitable for pinyon-juniper establishment during the late 1800s and early 1990s (Miller and Rose 1999). Pinyon-juniper removal has been widely implemented in Colorado and rangewide (CGSSC 2008). However, sage-grouse responses to pinyon-juniper removal remain poorly studied (Commons et al. 1999), and the timing and magnitude of greater sage-grouse responses following treatment is unknown. For this reason, it is difficult to judge whether pinyon-juniper removal can effectively increase available habitat and offset impacts from energy development. Since 2008, the Colorado Division of Wildlife, now Colorado Parks and Wildlife (CPW), and industry and landowner partners have been cooperating on research to assess the value of removing encroaching pinyon-juniper as a mitigation strategy in the PPR. The main objective of this study is to measure short-term (<5 years) responses of greater sage-grouse to experimental pinyon-juniper removal using changes in pellet occupancy in a before-after control-treatment framework. This progress report summarizes preliminary results from summer pellet surveys for the period June 2009 - August 2015. STUDY AREA Study plots are within or immediately adjacent to the current occupied range of greater sage-grouse in the PPR (Fig. 1). Birds in the PPR population inhabit the tops of ridges and plateaus dominated by mountain big sagebrush (Artemisia tridentata vaseyana) and a mixture of sagebrush and “mountain shrubs” (e.g., serviceberry, Amelanchier spp.; Gambel oak, Quercus gambelii, snowberry, Symphoricarpus sp.; antelope bitterbrush, Purshia tridentata, mountain mahogany, Cercocarpus sp., etc.). These areas are typically interspersed with patches of aspen (Populus tremuloides) or conifers. Sagebrush and mixed sagebrush-mountain shrub habitats at higher elevation give way to pinyon-juniper woodland on lower-elevation ridges that largely precludes use by sage-grouse. Our study plots are situated along the ecotone where pinyon-juniper is encroaching upslope into sagebrush and mixed sagebrush-mountain shrub habitat. 3 �METHODS Plot Selection I used vegetation, topography, marked bird locations, aerial photography, and on-site visits to identify nine study plots in 2008, 14 additional study plots in 2010 and 2011, and two additional plots in 2014 (Fig. 1). Study plots were selected based on: (1) density of pinyon-juniper; (2) shrub composition, density, and height; (3) topography; (4) proximity to areas of known use by greater sage-grouse; and (5) proximity to, and likelihood of, energy development within five years. All plots had a sagebrushdominated shrub layer, typically intermixed with mountain shrubs, and topography similar to habitats used by sage-grouse in the PPR from 2006-2010 (Apa 2010, Walker et al. 2015). The southeast portion of the PPR population is experiencing intensive energy development, but there is currently no development within the study plots and limited development nearby. Two of the plots added in 2011 (Upper and Lower Bar D) were treated by the Bureau of Land Management in January 2011 and were added opportunistically to our study. An additional plot (Lower Barnes) added in 2011 was treated by BLM in 2007-2008 and has been included in our study as a longer-term post-treatment plot for comparison. Assessing Response to Pinyon-Juniper Removal I used a before-after, control-treatment design to compare changes in sage-grouse pellet occupancy among control and removal plots before and after encroaching pinyon-juniper is removed. Caution must be exercised in interpreting results because estimates of pellet occupancy only give an index of frequency of use during a defined survey period, rather than a measure of abundance, density, habitat quality, or habitat selection (contra Dahlgren et al. 2006). There are three levels of treatment: 1) “PJTreatment” plots where encroaching pinyon-juniper is removed, 2) “PJ-Control” plots where encroaching pinyon-juniper is not removed, and 3) “Sagebrush-Control” plots with suitable sagebrush habitat and no pinyon-juniper encroachment. Data from PJ-Treatment plots are used to measure changes in pellet occupancy before and after removal. PJ-Control plots allow us to measure background changes and variation in pellet occupancy in areas with encroaching pinyon-juniper in the absence of treatment. Sagebrush-Control plots allow us to estimate background changes and variation in pellet occupancy in habitats already suitable for sage-grouse. Most plots were surveyed for one to three years prior to pinyonjuniper removal and will be surveyed for two to five years following removal. I established three study plots per treatment in fall 2008 for a total of nine original “survey” plots. I established 12 additional transect-based study plots in fall 2010 and two more transect-based plots in summer 2011 (Figs. 2-4), for a total of 23 study plots (nine survey, 14 transect). Summer Pellet Surveys and Transects I obtained an index of frequency of sage-grouse use of plots by surveying for pellets during the summer and estimating pellet occupancy. I used two different sampling techniques for pellet surveys. The first technique involves surveying a systematic random sample of 30 x 30 m sample units on each “survey” plot. The second technique involves surveying for pellets within 1.5 m on either side of linear transects spaced 50 m apart that ran the length of each “transect” study plot. With both sampling methods, field crews searched for, counted, and removed pellets from each sample unit (or transect line) within the plot once per year in July-August. For all pellets, field crews recorded their condition and appearance (crumbly-bleached vs. hard-dry, vs. fresh-wet) to estimate age and used composition to estimate when during the year they were deposited. Field crews identified those containing intact insect parts and flower heads as “summer” pellets (April-October) and those containing only digested sagebrush leaves as “winter” pellets (November-March) (Wallestad et al. 1975). Field crews recorded single pellets, pellet piles (i.e., day or night roost piles), and cecal droppings separately. Observers recorded pellets or groups of pellets within 10 cm of each other as one pile, with the constraint that pellets or groups of pellets > 10 cm apart could not be counted as the same pile. 4 �I opted to sample each plot once per year in July-August such that the “survey period” (i.e., the period during which birds can deposit pellets) was 12 months. Field crews marked all sample unit centers and transect lines with aluminum tags, high-visibility stakes and high-visibility flagging to ensure consistency in sampling locations across years. On survey plots, each observer carefully and thoroughly surveyed sample units by slowly walking 10 parallel 30-m lines spaced 3 m apart. On transect plots, observers survey for pellets by walking flagged transect lines and searching within 1.5 m on either side of the line. Observers recorded anecdotal evidence of occupancy while surveying (e.g., clockers, nests and eggs, feathers, birds, etc.). These methods have the following assumptions: 1) all pellets are correctly identified to species; 2) all pellets are correctly distinguished as either a chick or adult by size; 3) all pellets deposited during the survey period (during the previous year) are correctly distinguished from pellets deposited prior to the survey period by condition and appearance; 4) all pellets are correctly distinguished by season (“winter” vs. “summer”) by pellet composition; 5) surveying does not influence whether or not pellets are present in sampled units (or along transects). To address assumption 1, I trained observers to distinguish dusky grouse from sage-grouse pellets prior to surveys. Adult pellets of the two species can be distinguished by composition and smell in any season. Adult-sized sage-grouse typically consume 13-39% sagebrush throughout the spring and summer and >99% sagebrush in winter (Wallestad et al. 1975, Schroeder et al. 1999). For this reason, pellets of adult sage-grouse contain sagebrush year-round, and unlike dusky grouse, consistently smell like sage, even after a year in the field. To address assumption 2, I trained crews to distinguish adult from chick pellets by length and diameter. Analyses will only include data on adult-size pellets because it may not be possible to distinguish pellets of dusky grouse vs. sage-grouse chicks due to overlap in chick diets (both species consume primarily insects and forbs as chicks; Zwickel 1992, Drut et al. 1994). To address assumption 3, crews differentiated pellets in the field based on condition (bleached and crumbly vs. hard and dry vs. fresh and green/moist). I am also testing how pellet condition changes with age by placing piles of fresh test pellets within representative sagebrush habitat in the field and photographing changes in condition over time. I will test assumption 4 by testing how often observers correctly assess composition and season for pellets collected from marked birds in different seasons. Assumption 5 may be violated if surveyors flush birds that then land within another sample unit or along a transect line later surveyed. However, violation of this assumption is unlikely to meaningfully influence analyses because the number of pellets birds could deposit before the unit or transect gets surveyed (on the order of minutes or hours) is insignificant compared to the 12-month survey period. Pellet Detectability Detectability of sage-grouse pellets is typically low and may vary among observers, with pellet condition or appearance, and with distance from observer (Dahlgren et al. 2006). In 2009-2012, I estimated variation in detectability of individual pellets/pellet piles among observers by having each observer survey eight test sample units in which I placed piles of fresh pellets of various sizes at random directions and distances within the sample unit from the sample unit center. Pellets were also placed at random distances within 1.5 m along two 400-m long test transects in 2011 and 2012. Field crews also conducted repeat surveys of all survey plots on the same dates in 2013, 2014, and 2015 to allow estimation of detectability at the sample-unit level using unreconciled double-observer methods (Riddle et al. 2010), and conducted distance sampling on all Sagebrush-Control transect plots in 2014 and 2015 to allow estimation of pellet distance-detection curves for transect data. Pinyon-Juniper Removal All treatments were done by contractors using either a Bobcat with a Fecon head or a Hydro-axe. Contractors were instructed to remove only pinyon-juniper and to avoid removing sagebrush or mountain shrubs. Treatment started on the Black Sulphur plot in August 2009 and was completed in July 2010, the Upper Galloway plot was treated in November 2010, and the Ryan Gulch plot was treated in August 5 �2011. Among transect plots, Upper and Lower Bar D plots were treated by BLM in January 2011, and three plots (Cottonwood, Magnolia South, and Lower Wagonroad) were treated in August-November 2011. Two additional plots added in summer 2014 (Lower Ryan Gulch and Lower Galloway) are adjacent to two existing study plots (Upper Galloway and Upper Ryan Gulch) and were treated by WPX Energy (in conjunction with CPW and BLM) in fall 2014. RESULTS AND DISCUSSION Pellet Surveys and Transects Pellet survey data from 2009-2015 indicated substantially higher mean seasonal and year-round pellet detections on Sagebrush-Control survey plots than on PJ-Control plots or on PJ-Treatment plots prior to treatment (Table 1). Year-round pellet detections increased on the Upper Galloway and Ryan Gulch plots and have remained higher for 5 years following treatment (Fig. 2, Tables 1). However, no increase in pellets was detected on the Black Sulphur plot within 5 years following treatment. Preliminary comparison of repeated-count data suggests substantial variation in observer ability to detect pellets within 30 x 30 m sample units in all three years (Table 2). Analysis of repeated-count data are in progress. Field crews conducted one round of pellet surveys on each of 14 transect plots in July-August in each year from 2011-2015 (Table 3, Fig. 4). No transect plots showed any substantive increase in the no. pellet piles/km within four years following treatment with the exception of a temporary increase on a single plot in a single year (Upper Bar D in 2014). The no. of pellets counted per km of transect on the Lower Barnes plot (treated by BLM in 2007-2008) was comparable to Sagebrush-Control plots in 20112012, but decreased to levels comparable to those of PJ-Treatment plots from 2013-2015 (Table 3, Fig. 4). No pellets were counted on pre-treatment transects on the two new plots (Lower Galloway and Lower Ryan Gulch) established in 2014, but a handful pellets were detected post-treatment in 2015. Field crews collected distance sampling data on all Sagebrush-Control transect plots in 2014 and 2015 to generate pellet distance-detection curves for transect plots. Crews recorded 403 detections in 2014 and 273 detections in 2015. All pellets detected were within 2.85 m of the transect line. These data are currently being analyzed using program DISTANCE to generate distance-detection curves. Overall, summer pellet data indicated substantially greater pellet detections on Sagebrush-Control plots than on either PJ-Treatment plots prior to treatment or on PJ-Control plots as expected, but they also demonstrate substantial variation in pellet counts within and among Sagebrush-Control plots over time. An increase in sage-grouse pellet detections has only been observed on 2 of 8 treated plots within 4-5 years post-treatment. It is possible that populations take longer to respond to such treatments if few yearlings are available to colonize new habitat. However, our study was long enough to capture several years of high abundance. Alternatively, there may be unmeasured factors that hinder the response on some sites (e.g., too much surrounding forest). Also, sites selected for removals were generally on the edge of occupied range and may simply represent marginal habitat that gets reduced or occasional use. In that case, pellet detections may never increase to levels comparable to Sagebrush-Control plots. The number of pellets found on Sagebrush-Control plots has also been highly variable across years (this was especially evident in 2015) which suggests that there is substantial variation in the number of pellets deposited within any given area of suitable habitat as birds move around from year to year (over and above variation in counts due to observer bias). Such variation may be because our study sites are within a dynamic landscape and changes in the suitability of areas surrounding our study plots (e.g., due to energy development or other habitat treatments) may cause birds to shift which habitats they use from year to year. Such variation could also be attributable to birds moving around within our study plots enough that current sampling intensity is insufficient to consistently detect within-plot use. Although our data suggest a positive response of greater sage-grouse on at least two study plots, pinyon-juniper removal does not appear to be a consistently reliable mitigation option in the PPR. For that 6 �reason, we need to consider other habitat treatment options. An experimental project by Conoco-Phillips from 2013-2015 looked at changes in sage-grouse pellet detections and micro-site vegetation in response to combined pinyon-juniper and serviceberry treatments. Based on the apparent initial success of that project, we are now considering incorporating serviceberry treatments into our existing project. We would either conduct serviceberry treatments on our existing PJ-Treatment plots or conduct combined pinyonjuniper and serviceberry treatments on existing PJ-Control plots and continue pellet surveys to document initial response to such treatments. LITERATURE CITED Apa, A. D. 2010. Seasonal habitat use, movements, genetics, and vital rates in the Parachute-PiceanceRoan Population of greater sage-grouse. Unpublished progress report. Colorado Division of Wildlife. Fort Collins, USA. Becker, E. F. 1991. A terrestrial furbearer estimator based on probability sampling. Journal of Wildlife Management 55: 730-737. Becker, E. F., Golden, H. N., and Gardner, C. L. 2004. Using probability sampling of animal tracks in snow to estimate population size. In Thompson, W. L., ed., Sampling rare or elusive species: concepts and techniques for estimating population parameters. Island Press, Washington, D. C., USA, pp. 248-270. Becker, E. F., M. A. Spindler, and T. O. Osborne. 1998. A population estimator based on network sampling of tracks in the snow. Journal of Wildlife Management 62:968-977. Canfield, R. H. 1941. Application of the line interception method in sampling range vegetation. Journal of Forestry 39:388–394. Colorado Greater Sage-Grouse Steering Committee (CGSSC). 2008. Colorado greater sage-grouse conservation plan. Colorado Division of Wildlife, Denver, USA. Commons, M. L., R. K. Baydack, and C. E. Braun. 1999. Sage grouse response to pinyon-juniper management. Pages 238-239 in S. B. Monsen and R. Stevens, compilers. Proceedings: ecology and management of pinyon-juniper communities. RMRS-P-9. United States Department of Agriculture, Forest Service, Fort Collins, Colo. USA. Dahlgren, D. K., R. Chi, and T. A. Messmer. 2006. Greater sage-grouse response to sagebrush management in Utah. Wildlife Society Bulletin 34:975-985. Department of the Interior (DOI). 2010. 12-month finding for petitions to list the greater sage-grouse as threatened or endangered. Federal Register 75(55): 13910-14014. Drut, M. S., W. H. Pyle, and J. A. Crawford. 1994. Technical note: Diets and food selection of Sage Grouse chicks in Oregon. Journal of Range Management 47:90-93. Miller, R. F. and J. A. Rose.1999. Fire history and western juniper encroachment in sagebrush steppe. Journal of Range Management 52:550-559. Schroeder, M. A., C. L. Aldridge, A. D. Apa, J. R. Bohne, C. E. Braun, S. D. Bunnell, J. W. Connelly, P. A. Deibert, S. C. Gardner, M. A. Hilliard, G. D. Kobriger, C. W. Mccarthy. 2004. Distribution of Sage-grouse in North America. Condor 106:363-376. Schroeder, M. A., J. R. Young, and C. E. Braun. 1999. Sage-grouse (Centrocercus urophasianus). Account 425 in A. Poole and F. Gill, editors. The birds of North America. The Academy of Natural Sciences, Philadelphia, Pa. USA. Walker, B. L. 2010. Greater sage-grouse research in the Parachute-Piceance-Roan region of western Colorado: multi-scale habitat selection and seasonal habitat mapping. Unpublished interim progress report. Colorado Division of Wildlife. Fort Collins, USA. Wallestad, R., J. G. Peterson, and R. L. Eng. 1975. Foods of adult sage grouse in central Montana. Journal of Wildlife Management 39:628-630. Zwickel, F. C. 1992. Blue Grouse (Dendragapus obscurus). Account 15 in A. Poole, P. Stettenheim, and F. Gill, editors. The birds of North America. The Academy of Natural Sciences, Philadelphia, Pa. USA. 7 �Table 1. Preliminary estimates of proportion of sample units ± SE containing greater sage-grouse pellets (from any season) on survey plots in the ParachutePiceance-Roan population of western Colorado, USA from 2009-2014. Values presented do not account for sample-unit level variation in pellet detectability. PJ-Treatment Plotsa PJ-Control (No Treatment) Plots Sagebrush-Control Plots 1-Upper 2-Black 3-Ryan MEAN 1-Dry 3-Stake MEAN 1-Dry 2-Canyon 3-Black MEAN Galloway Sulphur Gulch ± SE Ryan 2-Eureka Springs ± SE Gulch Creek Cabin ± SE b b b c Year n = 49 n = 38 n = 48 N=3 n = 35 n = 50 n = 38 N=3 n = 54 n = 41 n = 42 N=3 d 2009 0.082 0.000 0.146 0.076 0.000 0.040 0.105 0.048 0.444 0.293 0.452 0.397 ± 0.039 ± 0.000 ± 0.051 ± 0.042 ± 0.000 ± 0.033 ± 0.05 ± 0.031 ± 0.068 ± 0.071 ± 0.077 ± 0.052 2010 0.000 0.104 0.052 0.029 0.040 0.026 0.032 0.721 0.293 0.333 0.449 0.026 ± 0.000 ± 0.026 ± 0.044 ± 0.052 ± 0.028 ± 0.028 ± 0.026 ± 0.004 ± 0.068 ± 0.071 ± 0.073 ± 0.136 2011 0.063 0.000 0.020 0.000 0.007 0.349 0.171 0.071 0.197 0.082 0.000 0.041 ± 0.035 ± 0.041 ± 0.000 ± 0.020 ± 0.000 ± 0.007 ± 0.073 ± 0.059 ± 0.040 ± 0.081 ± 0.039 ± 0.000 2012 0.029 0.040 0.000 0.023 0.605 0.341 0.262 0.403 0.245 0.026 0.188 0.153 ± 0.028 ± 0.028 ± 0.000 ± 0.012 ± 0.075 ± 0.074 ± 0.068 ± 0.104 ± 0.061 ± 0.026 ± 0.056 ± 0.065 2013 0.000 0.100 0.000 0.033 0.605 0.220 0.381 0.402 0.082 0.000 0.188 0.090 ± 0.000 ± 0.042 ± 0.000 ± 0.033 ± 0.075 ± 0.065 ± 0.075 ± 0.112 ± 0.039 ± 0.000 ± 0.056 ± 0.054 2014 0.000 0.000 0.026 0.009 0.535 0.146 0.381 0.354 0.082 0.000 0.333 0.138 ± 0.000 ± 0.000 ± 0.026 ± 0.009 ± 0.076 ± 0.055 ± 0.075 ± 0.113 ± 0.039 ± 0.000 ± 0.068 ± 0.100 2015 0.029 0.000 0.000 0.010 0.372 0.000 0.571 0.315 0.245 0.000 0.292 0.179 ± 0.028 ± 0.000 ± 0.000 ± 0.010 ± 0.074 ± 0.000 ± 0.076 ± 0.167 ± 0.061 ± 0.000 ± 0.066 ± 0.090 a Values in bold represent post-treatment data. Numbers before plot names refer to set (e.g., Set 1 = Upper Galloway, Dry Ryan, Dry Gulch, etc.). b n refers to no. of 30 x 30 m units sampled within the study plot. c N refers to no. of study plots contributing to the mean. Means in bold are for post-treatment plots, otherwise values represent pre-treatment data. d p = proportion of sample units per plots in which greater sage-grouse pellets were detected. Subscripts refer to year. 8 �Table 2. Preliminary data on observer variation in estimates of proportion of sample units with greater sage-grouse pellets (from any season) on survey plots from repeat surveys in the Parachute-Piceance-Roan population of western Colorado, USA in 2013, 2014, and 2015. Values presented do not account for variation in sample-unit level detectability of pellets. Surveys of each sample unit were conducted by a different observer within 20-30 minutes of each other on the same date. PJ-Treatment Plots (post-treatment) PJ-Control (No Treatment) Plots Sagebrush-Control Plots 1-Upper Galloway n = 49a 2-Black Sulphur n = 38a 3-Ryan Gulch n = 48a MEAN ± SE N = 3b 1-Dry Ryan n = 35 3-Stake Springs n = 38 MEAN ± SE N=3 0.000 ± 0.000 0.000 ± 0.000 0.013 ± 0.013 0.033 ± 0.033 0.465 ± 0.076 0.605 ± 0.075 0.195 ± 0.062 0.220 ± 0.065 0.238 ± 0.066 0.381 ± 0.075 0.299 ± 0.084 0.402 ± 0.112 0.026 ± 0.026 0.026 ± 0.026 0.009 ± 0.009 0.052 ± 0.024 0.535 ± 0.076 0.488 ± 0.076 0.146 ± 0.055 0.098 ± 0.046 0.381 ± 0.075 0.548 ± 0.077 0.354 ± 0.113 0.378 ± 0.141 0.286 0.000 0.271 0.186 0.057 0.000 0.000 0.019 0.465 ± 0.065 ± 0.000 ± 0.064 ± 0.093 ± 0.039 ± 0.000 ± 0.000 ± 0.019 ± 0.076 pBc 0.245 0.000 0.292 0.179 0.029 0.000 0.000 0.010 0.372 ± 0.061 ± 0.000 ± 0.066 ± 0.090 ± 0.028 ± 0.000 ± 0.000 ± 0.010 ± 0.074 a n refers to the number of sample units per study plot. b N refers to the no. of study plots contributing to the mean. c p = proportion of sample units in which greater sage-grouse pellets were detected. Subscript refers observer (A or B). 0.024 ± 0.024 0.000 ± 0.000 0.548 ± 0.077 0.571 ± 0.076 0.346 ± 0.162 0.315 ± 0.167 2-Eureka n = 50 1-Dry Gulch n = 43 2-Canyon Creek n = 41 3-Black Cabin n = 42 MEAN ± SE N=3 2013 pAc pBc 0.224 ± 0.060 0.082 ± 0.039 0.000 ± 0.000 0.000 ± 0.000 0.167 ± 0.054 0.188 ± 0.056 0.130 ± 0.067 0.090 ± 0.054 0.000 ± 0.000 0.000 ± 0.000 0.040 ± 0.028 0.100 ± 0.042 2014 pAc pBc 0.082 ± 0.039 0.184 ± 0.055 0.000 ± 0.000 0.000 ± 0.000 0.333 ± 0.068 0.250 ± 0.063 0.138 ± 0.100 0.145 ± 0.075 0.000 ± 0.000 0.029 ± 0.028 0.000 ± 0.000 0.100 ± 0.042 2015 pAc 9 �Table 3. Preliminary estimates of greater sage-grouse pellets per kilometer (from any season) encountered on transect plots in the Parachute-Piceance-Roan population of western Colorado, USA from 2011-2014. Values presented do not account for variation in pellet detectability with distance. PJ-Treatment Plotsa PJ-Control (No Treatment) Plots Sagebrush-Control Plots Lower Upper Bar Upper WagonMagnolia Cotton- Wagon- Lower Upper Lower Magnolia WagonD Magnolia Barnes road Bar D South wood road Bar D Bar D Barnes North Sprague road Split Control Control Control Control x2011b 0.10 0.00 0.00 0.00 0.00 0.00 0.00 18.82 13.51 6.46 5.61 0.00 0.00 13.78 c X2011 0.03 ± 0.03 0.00 ± 0.00 11.10 ± 3.84 0.00 ± 0.00 x2012 X2012 2.86 x2013 X2013 0.31 x2014 X2014 2.14 x2015 X2015 0.00 kmd 9.80 0.27 0.00 0.75 ± 0.54 0.00 0.00 0.17 ± 0.11 0.00 0.00 2.24 ± 1.73 0.00 0.00 0.55 ± 0.53 0.00 0.63 25.51 - 2.02 0.00 0.31 0.58 ± 0.42 0.00 46.03 7.94 31.63 27.14 ± 7.97 22.96 0.52 0.00 2.89 - 0.00 0.00 0.00 0.00 ± 0.00 0.00 18.53 1.01 11.56 22.79 ± 12.93 60.03 0.10 8.96 3.91 - 0.00 0.00 0.10 0.03 ± 0.03 0.00 19.41 4.22 15.31 18.03 ± 5.98 33.16 0.10 2.67 0.00 - 0.00 0.00 0.10 0.03 ± 0.03 0.00 0.00 0.51 0.00 14.29 ± 14.12 56.63 7.52 7.64 9.58 6.36 5.88 6.44 12.52 9.80 4.68 6.80 5.92 5.88 5.88 (7.70) (13.40) a Post-treatment data are in bold. Treatments on Lower Bar D and Upper Bar D occurred in Jan 2011. Data for Lower Bar D and Upper Bar D from 2011-2015 represent ~6, 18, 30, 42, and 54 mo post-treatment, respectively. Treatments on Lower Barnes were started by the Bureau of Land Management in summer 2007 and completed in summer 2008. Post-treatment data on Lower Barnes were collected opportunistically and are presented for comparison only. b x = no. pellet piles detected per km of transect. c X = mean no. pellet piles detected per km of transect across study plots within each treatment. Values for Lower Barnes are presented separately. The 2011 mean for Lower Bar D and Upper Bar D in 2011 represents post-treatment data and is presented separately from the 2011 mean for other PJ-Treatment plots that had not yet been treated (Magnolia South, Cottonwood, Lower Wagonroad). d Total km of transect line surveyed per plot. Portions of transects on Cottonwood and Sprague unsuitable as greater sage-grouse habitat were eliminated in 2012, values in parentheses indicate km surveyed in 2011 only. 10 �Table 4. Timeline for research on greater sage-grouse response to pinyon-juniper removal in the ParachutePiceance-Roan population, western Colorado, 2008-2015. Task Identification of plots for pinyon-juniper removal Remove pinyon-juniper on survey treatment plots (2009-2011) Remove pinyon-juniper on transect treatment plots (2011) Remove pinyon-juniper on new transect treatment plots (2014) Pellet surveys (annually) Prepare cumulative report (annually) Prepare cumulative final report 11 Initiation Summer 2008 Fall 2009 Fall 2011 Fall 2014 June-Aug September 1 Sep 2015 Completion COMPLETED COMPLETED COMPLETED COMPLETED COMPLETED COMPLETED COMPLETED �Fig. 1. Map of study plot locations for the pinyon-juniper removal experiment and greater sage-grouse occupied range boundary (as of 2012) in the northern portion of the Parachute-Piceance-Roan population of western Colorado, USA. 12 �Fig. 2. Trends in the proportion of sample units detected with greater sage-grouse pellets for individual survey plots (color-coded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2009-2015. Values presented do not account for variation in sample-unit level detectability of pellets. 13 �Fig. 3. Trends in the mean proportion of sample units detected with greater sage-grouse pellets across survey plots (color-coded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2009-2015. Values presented do not account for variation in sample-unit level detectability of pellets. 14 �Fig. 4. Trends in the no. of greater sage-grouse pellets counted per km of transect for individual transect plots (color-coded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2011-2015. Values presented do not account for variation in detectability of pellets with distance from transect. 15 �Fig. 5. Trends in the mean no. of greater sage-grouse pellets counted per km of transect across transect plots within treatments (colorcoded by treatment) in the Parachute-Piceance-Roan population of western Colorado, USA, 2011-2015. Values presented do not account for variation in detectability of pellets with distance from transect. 16 � https://cpw.cvlcollections.org/files/original/86dedfa3be311826ffa281b00d4ab812.pdf b8ca82be1a5120853e9df70bde9896d0 PDF Text Text Colorado Division of Parks and Wildlife September 2015-September 2016 WILDLIFE RESEARCH REPORT State of: Cost Center: Work Package: Task No.: Colorado 3420 0660 N/A Federal Aid Project No. N/A : : : : Division of Parks and Wildlife Avian Research Greater Sage-grouse Conservation Assessment of Greater Sage-grouse Response to Pinyon-Juniper Removal in the ParachutePiceance-Roan Population of Northwestern Colorado Period Covered: September 1, 2015 – August 31, 2016 Author: B. L. Walker Personnel: B. Holmes, B. Petch, T. Knowles, B. deVergie All information in this report is preliminary and subject to further evaluation. Information MAY NOT BE PUBLISHED OR QUOTED without permission of the author. Manipulation of these data beyond that contained in this report is discouraged. EXTENDED ABSTRACT Greater sage-grouse (Centrocercus urophasianus) in the Parachute-Piceance-Roan (PPR) region of western Colorado face at least two major potential stressors: projected habitat loss from energy development and a long-term decline in habitat suitability associated with pinyon-juniper (PJ) encroachment. Pinyon-juniper removal may be a useful mitigation tool to offset potential habitat losses associated with energy development. Although pinyon-juniper removal is commonly used to improve habitat for greater sage-grouse, no studies to date have quantified the timing or magnitude of how birds respond to treatments. Since 2008, Colorado Parks and Wildlife (CPW) has cooperated with industry and landowner partners to investigate the effectiveness of pinyon-juniper removal for restoring sage-grouse habitat in the PPR. In fall 2008, I established nine “survey” study plots, arranged in three groups of three, with each group consisting of a Sagebrush-Control plot, an untreated PJ-Control plot, and a PJ-treatment plot. Treatments were completed on three survey plots in 2010 and 2011. Pellet surveys in summer from 2009-2015 indicated that the mean proportion of sample units containing pellets was consistently highest on sagebrush control plots (range 0.197-0.449 across years), consistently lowest on plots with encroaching pinyon-juniper (range 0.007-0.048), and increased on 2 of 3 treated survey plots (Ryan Gulch and Upper Galloway) within 1-2 years after treatment. Fourteen transect plots were established in fall 2010 and summer 2011, and two were established in summer 2014. Transect plots were surveyed for pellets in summer though 2015. As expected, estimated mean pellet piles/km were low on the four PJControl plots for the duration of the study (range across years = 0.00-0.58 pellets/km) and on PJTreatment plots prior to treatment (mean = 0.03 pellet piles/km). Mean pellet piles/km were consistently higher on all four Sagebrush-Control transect plots through 2014 (range across years = 11.10 - 27.14 pellet piles/km), but declined precipitously on 3 of 4 Sagebrush-Control plots in 2015 (Magnolia Control, Upper Barnes Control, and Wagonroad Control). Pellet piles/km were also high on the Lower Barnes transect plot 4-5 years post-treatment (13.78-25.71 piles/km), but declined 6-8 years post-treatment (0.003.91 pellet piles/km). Mean pellet piles/km has generally remained low on treated transect plots for four 1 �years after pinyon-juniper removal (range across years = 0.00 - 2.86 pellet piles/km) with the exception of Upper Bar D in 2014 (8.96 pellet piles/km). Estimates of proportion of sample units with pellets (from survey plots) and of pellet piles/km (from transect plots) also varied substantially among SagebrushControl plots within years and among years within plots, which suggests there is substantial variation in pellets deposited within suitable habitat (i.e., over and above variation in counts due to observer bias). We completed double-observer sampling on survey plots in 2013, 2014, and 2015 to estimate sample unitlevel detectability, and we completed distance sampling on transect plots in 2014 and 2015 to generate distance-detection curves, and those analyses are in progress. We established and conducted pre- and post-treatment surveys on two additional transect plots (Lower Galloway and Lower Ryan Gulch) in summer 2014 and 2015. Analyses for this project are in progress. However, to date, sage-grouse response to pinyon-juniper removal as measured by pellet surveys appears to be inconsistent, with pellet counts increasing on only 2 of 8 plots within 4-5 years post-treatment. A recent experimental pilot project suggests that sage-grouse may respond more strongly to both pinyon-juniper and serviceberry removal. We are developing a proposal to expand the current project to include pinyon-juniper and/or serviceberry treatments on existing and additional study plots starting in fall 2018. 2 � Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Reports Text A resource consisting primarily of words for reading. Examples include books, letters, dissertations, poems, newspapers, articles, archives of mailing lists. Note that facsimiles or images of texts are still of the genre Text. Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Assessment of greater sage-grouse response to pinyon-juniper removal in the Parachute-Piceance-Roan population of northwestern Colorado Description An account of the resource Greater sage-grouse (<em>Centrocercus urophasianus</em>) in the Parachute-Piceance-Roan (PPR) region of western Colorado face at least two major potential stressors: projected habitat loss from energy development and a long-term decline in habitat suitability associated with pinyon-juniper (PJ) encroachment. PJ removal may be a useful mitigation tool to offset potential habitat losses associated with energy development. Although PJ removal is commonly used to improve habitat for greater sage-grouse, no studies to date have quantified the timing or magnitude of how birds respond to treatments. Since 2008, Colorado Parks and Wildlife (CPW) has cooperated with industry and landowner partners to investigate the effectiveness of PJ removal for restoring sage-grouse habitat in the PPR. In fall 2008, I established nine “survey” study plots, arranged in three groups of three, with each group consisting of a sagebrush control plot, an untreated PJ control plot, and a PJ treatment plot. Treatments were completed on the three treatment plots in 2010 and 2011. Creator An entity primarily responsible for making the resource Walker, Brett L. Subject The topic of the resource Greater sage-grouse <em>Centrocercus urophasianus</em> Parachute-Piceance-Roan (PPR) region Wildlife habitat improvement Northwestern Colorado Extent The size or duration of the resource. various pages Date Created Date of creation of the resource. 2014-2016 Rights Information about rights held in and over the resource <a href="http://rightsstatements.org/vocab/NoC-NC/1.0/">No Copyright - Non-Commercial Use Only</a> Type The nature or genre of the resource Text Format The file format, physical medium, or dimensions of the resource application/pdf Language A language of the resource English Is Part Of A related resource in which the described resource is physically or logically included. Cost Center 3420 Avian Research. Work Package 0660 Greater Sage-grouse conservation