| From the field: Outbreak of West Nile virus in greater sage-grouse and guidelines for monitoring, handling, and submitting dead birds | Walker, BL | 2004 |
KeywordsCentrocercus urophasianus, emerging infectious disease, greater sage-grouse, lek count, Montana, population decline, Powder River Basin, survival, West Nile virus, Wyoming AbstractWest Nile virus (WNV) resulted in a 25% decline in survival in four populations of radiomarked greater sage-grouse (Centrocercus urophasianus) across Alberta, Wyoming, and Montana in 2003. Unexpected impacts of WNV are disturbing because range-wide habitat loss and degradation already threaten sage-grouse populations. In the Powder River Basin of Wyoming and Montana, late-summer survival of sage-grouse was lower at a site with confirmed WNV mortalities (20%) than at two sites without (76%). Dramatic declines in both male and female lek attendance at the WNV site the following spring suggest that outbreaks may threaten some local populations with extirpation. The key to understanding broader impacts of WNV on sage-grouse is to monitor additional populations and to determine whether populations infected in 2003 are again impacted this year. To facilitate this process, we describe a strategy for monitoring WNV mortality in the field and provide information on how to handle, store, and submit dead birds for testing. AuthorsWalker, BL; Naugle, DE; Doherty, KE; Cornish, TE Year Published2004 PublicationWildlife Society Bulletin LocationsDOI10.2193/0091-7648(2004)032[1000:FTFOOW]2.0.CO;2 |
| Evaluation of the lek-count index for greater sage-grouse | Walsh, DP | 2004 |
Keywordsbounded count, Centrocercus urophasianus, detection probability, greater sage-grouse, index, lek-attendance rates, lek counts, mark–resight, prairie grouse AbstractCounts of birds attending leks traditionally have been used as an index to the population size of greater sage-grouse (Centrocercus urophasianus) and, more recently, as a means to estimate population size. The relationship between this index and the actual population has not been studied. We used intensive counts of individually marked and unmarked greater sage-grouse on leks to evaluate how sex and age of birds, time of day, and time of season impact lek-attendance patterns and lek counts. These within-season sources of variation need to be considered when estimating detection probability of birds on leks and ultimately adjusting the lek-count index to estimate true population parameters. On average, 42% of marked adult males, 4% of marked hens, and 19% of yearling males were observed on leks per sighting occasion with all 15 known leks being intensively counted. We discovered that lek counts as currently conducted may be useful as an index to greater sage-grouse populations, but standardization of protocols is needed to allow for better spatial and temporal comparisons of lek-count data. Also the probability of detecting birds on leks must be estimated in order to relate lek counts to population parameters. Lastly, we evaluated use of the bounded-count methodology for correcting lek-count data. We showed large biases associated with this technique and below-nominal coverage of confidence intervals even at large numbers of counts, demonstrating the unreliability of the bounded-count method to correct lek-count data. AuthorsWalsh, DP; White, GC; Remington, TE; Bowden, DC Year Published2004 PublicationWildlife Society Bulletin LocationsDOI10.2193/0091-7648(2004)32[56:EOTLIF]2.0.CO;2 |
| Adaptive management of prairie grouse: how do we get there? | Aldridge, CL | 2004 |
Keywordsadaptive management, Alberta, Centrocercus urophasianus, conservation plans, grazing, greater sage-grouse, habitat, Manitoba, policy planning, prairie sharp-tailed grouse, Tympanuchus phasianellus AbstractManaging prairie grouse has been largely a reactive process without any "true" management experiments being implemented, thereby limiting our ability to learn from management and enhance conservation efforts for declining prairie grouse populations. In a few cases where the potential existed for a passive or active adaptive approach, monitoring was insufficient to detect effects of changes in management practices. Similar problems appear to occur at planning stages in attempts to implement adaptive management for prairie grouse populations, preventing proper consideration of sound adaptive experiments that advance learning. Successful adaptive management begins with stakeholder gatherings following a policy planning process, which includes many steps, beginning with goal identification and understanding of uncertainties and culminating in model simulations to understand potential management policies. By following this process, the opportunity to implement successful management experiments can be enhanced. We discuss the successes and failures of prairie grouse management using 2 case studies, 1 for prairie sharp-tailcd grouse (Tympanuchus phasianellus) in Manitoba and 1 for greater sage-grouse (Centrocercus urophasianus) in southern Alberta. We describe ways in which active adaptive management could improve our understanding of prairie grouse population declines and outline a policy planning process that, if followed, will allow adaptive management to be successfully implemented, enhancing prairie grouse management and conservation. AuthorsAldridge, CL; Boyce, MS; Baydack, RK Year Published2004 PublicationWildlife Society Bulletin LocationsDOI10.2193/0091-7648(2004)32[92:AMOPGH]2.0.CO;2 |
| Occupied and unoccupied sage grouse habitat in Strawberry Valley, Utah | Bunnell, KD | 2004 |
KeywordsCentrocercus urophasianus, logistic regression, sagebrush, sage grouse AbstractThis study evaluated multiple aspects of spring/summer sage grouse (Centrocercus urophasianus) habitat in Strawberry Valley, Utah by measuring vegetation associated with nest, brood and adult use sites. In addition, 3 types of random habitats were measured including available habitat within core use areas, random sagebrush (Artemisia spp.)/grass habitat outside core use are-as, and random sagebrush/grass habitat sites that had been converted to an understory of smooth brome (Bromus inermis Leyss) by past range management practices. Logistic regression was used to identify those habitat variables that discriminated between site types. Variables that discriminated adult habitat from brood rearing habitat included: 1) sagebrush height (P less than or equal to 0.01) and 2) forb diversity (P = 0.12) with sagebrush height being greater at adult sites and forb diversity greater at brood sites Variables that significantly discriminated occupied adult habitat from random habitat outside of core use areas included: 1) percent grass cover (P less than or equal to 0.01) and 2) area of sagebrush canopy (P = 0.03) with both variables having grater values in adult habitat. Variables that significantly discriminated occupied adult habitat from random habitat with a smooth brome understory included: 1) percent forb cover (P less than or equal to 0.01), 2) shrub canopy cover (P = 0.02), and 3) area of sagebrush canopy (P = 0.08) with all variables being greater in adult habitat. In addition, this study identified sagebrush age, sagebrush canopy area, and forb diversity as potentially important aspects of sage grouse habitat that have not been previously reported. AuthorsBunnell, KD; Flinders, JT; Mitchell, DL; Warder, JH Year Published2004 PublicationJournal of Range Management LocationsDOI10.2307/4003983 |
| History of greater sage-grouse in the Dakotas: Distribution and population trends | Smith, Joe T. | 2004 |
History of greater sage-grouse in the Dakotas: Distribution and population trendsKeywordsactive, lek, Centrocercus urophasianus, greater sage-grouse, North Dakota, South Dakota AbstractThe greater sage-grouse (Centrocercus urophasianus) has declined throughout its range and its status is of major concern to federal, state, and provincial wildlife agencies. We collected information on current and historical greater sage-grouse distribution and lek activity in western North and South Dakota. A steady decline in lek attendance by males occurred over the entire recorded period in North Dakota (1951-2002) and South Dakota (1972-2002). There was no apparent change in numbers of known active leks due to discovery of new leks, but there was an abandonment of regions once occupied by active leks. AuthorsSmith, Joe T.; Flake, Lester D.; Higgins, Kenneth F.; Kobriger, Gerald D. Year Published2004 PublicationPrairie Naturalist Locations |
| The effects of raven removal on sage grouse nest success. | Coates, Peter S. | 2004 |
The effects of raven removal on sage grouse nest success.KeywordsCentrocercus urophasianus, nest success, predator control, raven damage management, sage grouse, video nest monitoring AbstractNo abstract available AuthorsCoates, Peter S.; Delehanty, David J. Year Published2004 PublicationProceedings of The Vertebrate Pest Conference Locations |
| Ecology and management of sage-grouse and sage-grouse habitat | Crawford, John A. | 2004 |
Keywordspopulation dynamics, habitat, fire ecology, livestock grazing, herbicide, landscape ecology AbstractSage-grouse (Centrocercus urophasianus and C. minimus) historically inhabited much of the sagebrush-dominated habitat of North America. Today, sage-grouse populations are declining throughout most of their range. Population dynamics of sage-grouse are marked by strong cyclic behavior. Adult survival is high, but is offset by low juvenile survival, resulting in low productivity. Habitat for sage-grouse varies strongly by life-history stage. Critical habitat components include adequate canopy cover of tall grasses (≥ 18 cm) and medium height shrubs (40–80 cm) for nesting, abundant forbs and insects for brood rearing, and availability of herbaceous riparian species for late-growing season foraging. Fire ecology of sage-grouse habitat changed dramatically with European settlement. In high elevation sagebrush habitat, fire return intervals have increased (from 12–24 to > 50 years) resulting in invasion of conifers and a consequent loss of understory herbaceous and shrub canopy cover. In lower elevation sagebrush habitat, fire return intervals have decreased dramatically (from 50–100 to < 10 years) due to invasion by annual grasses, causing loss of perennial bunchgrasses and shrubs. Livestock grazing can have negative or positive impacts on sage-grouse habitat depending on the timing and intensity of grazing, and which habitat element is being considered. Early season light to moderate grazing can promote forb abundance/availability in both upland and riparian habitats. Heavier levels of utilization decrease herbaceous cover, and may promote invasion by undesirable species. At rates intended to produce high sagebrush kill, herbicide-based control of big sagebrush may result in decreased habitat quality for sage-grouse. Light applications of tebuthiuron (N-[5-(1,1-dimethylethyl)-1,3,4-thiadiazol-2-yl]-N,N′-dimethylurea) can decrease canopy cover of sagebrush and increase grass and forb production which may be locally important to nesting and foraging activities. The ability of resource managers to address sage-grouse habitat concerns at large scales is aided greatly by geomatics technology and advances in landscape ecology. These tools allow unprecedented linkage of habitat and population dynamics data over space and time and can be used to retroactively assess such relationships using archived imagery. The present sage-grouse decline is a complex issue that is likely associated with multiple causative factors. Solving management issues associated with the decline will require unprecedented cooperation among wildlife biology, range science, and other professional disciplines. AuthorsSchroeder, Michael A., Crawford, John A., Miller, Richard F., Boyd, Chad S., Mosley, Jeffrey C., Gregg, Michael A., OLSON, RICH A., WEST, NEIL E. and WHITSON, TOM D. Year Published2004 PublicationRangeland Ecology & Management LocationsDOI10.2111/1551-5028(2004)057[0002:EAMOSA]2.0.CO;2 |
| Silver Sagebrush Community Associations in Southeastern Alberta, Canada. | Jones, Paul F | 2005 |
Keywordsdistribution ; greater sage-grouse ; height ; occupancy ; site AbstractGreater sage-grouse (Centrocercus urophasianus) habitat in southeastern Alberta is limited by the distribution of silver sagebrush (Artemisia cana Pursh). We conducted a landscape assessment of silver sagebrush throughout the current range of sage-grouse in southeastern Alberta. Black-and-white aerial photography acquired in the fall of 2001 was used to map silver sagebrush. Contact print stereo pairs were interpreted using a stereoscope and initially classified into 1 of 13 site classes based on soil type and landscape feature (e.g., recent agriculture). Each site polygon was further broken down into smaller polygons based on the percentage of silver sagebrush occupancy, density distribution, and height. A total of 4626 site polygons were identified and classed into 1 of 13 site classes. To ensure all assumptions of statistical tests were met, the data set was reduced to 9 site classes. The mean percentage of silver sagebrush occupancy was significantly different between the 9 site classes (F=... AuthorsPaul F Jones, Roy Penniket, Livio Fent, Joel Nicholson, Barry Adams Year Published2005 PublicationRangeland Ecology & Management LocationsDOI10.2111/1551-5028(2005)058[0400:SSCAIS]2.0.CO;2 |
| Timing of Vegetation Sampling at Greater Sage-Grouse Nests. | Hausleitner, Doris | 2005 |
KeywordsCentrocercus urophasianus ; Colorado ; nest site selection ; nest initiation AbstractHabitat management guidelines for greater sage-grouse, Centrocercus urophasianus, have been formulated, in part, based on studies of nest site selection. However, these guidelines may not represent conditions when the female initiates nesting because sampling occurs posthatch (> 30 days after nest initiation) to avoid disturbing incubating females. In 2002, we investigated differences in 22 habitat variables at initiation and hatch. Sampling was at 30 randomly selected active nests marked in 2001. There was no significant difference in structural or cover data (P > 0.05). Grass height and percent grass cover differed (P < 0.05) based on timing of sampling. Grass heights at the nest bowl and at 1 m from the edge of the nest bowl were 10 and 9 cm at initiation and 16 and 13 cm at hatch, respectively. Percent grass cover increased from 4% to 6% cover from initiation to hatch. Sampling occurred in a dry year; differences in grass heights and percent cover may be more pronounced in years of normal precipitation. Preliminary results indicated current habitat sampling techniques conducted posthatching adequately described selection of structural components of shrub height, visual obstruction, and percent cover of shrubs, bare ground, litter, and forbs at the nest site at initiation. Data need to be verified for other study areas and under different climatic conditions. AuthorsDoris Hausleitner, Kerry P Reese, Anthony D Apa Year Published2005 PublicationRangeland Ecology & Management LocationsDOI10.2111/04-170R2.1 |
| Modeling sage grouse: Progressive computational methods for linking a complex set of local, digital biodiversity and habitat data towards global conservation statements and decision-making systems | Onyeahialam, A | 2005 |
KeywordsNo keywords available AbstractModem conservation management needs to link biological questions with computational approaches. As a global template, here we present such an approach from a local study on sage grouse breeding habitat, leks, in North Natrona County, Wyoming, using remote sensing imagery, digital datasets, spatial statistics, predictive modelling and a Geographic Information System (GIS). Four quantitative models that describe sage grouse breeding habitat selection were developed for multiple scales using logistic regression and multivariate adaptive regression splines (MARS-Salford Systems). Based on candidate models and AIC, important habitat predictor variables were elevation, distance to human development, slope, distance to roads, NDVI and distance to water, but not Sagebrush. Some predictors changed when using different scales and MARS. For the year 2011, a cumulative prediction index approach is presented on how the population viability of sage grouse can be assessed over time and space using Markov chain models for deriving future landscape scenarios and MARS for species predictions. AuthorsOnyeahialam, A; Huettmann, F; Bertazzon, S Year Published2005 PublicationComputational Science And Its Applications - Iccsa 2005, Pt 3 LocationsDOI10.1007/11424857_17 |
