| Experimental Evidence for the Effects of Chronic Anthropogenic Noise on Abundance of Greater Sage-Grouse at Leks | Blickley, Jessica L. | 2012 |
Keywordschronic noise, energy development, Centrocercus urophasianus roads AbstractIncreasing evidence suggests that chronic noise from human activities negatively affects wild animals, but most studies have failed to separate the effects of chronic noise from confounding factors, such as habitat fragmentation. We played back recorded continuous and intermittent anthropogenic sounds associated with natural gas drilling and roads at leks of Greater Sage-Grouse (Centrocercus urophasianus). For 3 breeding seasons, we monitored sage grouse abundance at leks with and without noise. Peak male attendance (i.e., abundance) at leks experimentally treated with noise from natural gas drilling and roads decreased 29% and 73%, respectively, relative to paired controls. Decreases in abundance at leks treated with noise occurred in the first year of the study and continued throughout the experiment. Noise playback did not have a cumulative effect over time on peak male attendance. There was limited evidence for an effect of noise playback on peak female attendance at leks or male attendance the year after the experiment ended. Our results suggest that sage-grouse avoid leks with anthropogenic noise and that intermittent noise has a greater effect on attendance than continuous noise. Our results highlight the threat of anthropogenic noise to population viability for this and other sensitive species. AuthorsBlickley, Jessica L.; Blackwood, Diane; Patricelli, Gail L. Year Published2012 PublicationConservation Biology LocationsDOI10.1111/j.1523-1739.2012.01840.x |
| Experimental Chronic Noise Is Related to Elevated Fecal Corticosteroid Metabolites in Lekking Male Greater Sage-Grouse (Centrocercus urophasianus) | Blickley, Jessica L. | 2012 |
KeywordsNo keywords available AbstractThere is increasing evidence that individuals in many species avoid areas exposed to chronic anthropogenic noise, but the impact of noise on those who remain in these habitats is unclear. One potential impact is chronic physiological stress, which can affect disease resistance, survival and reproductive success. Previous studies have found evidence of elevated stress-related hormones (glucocorticoids) in wildlife exposed to human activities, but the impacts of noise alone are difficult to separate from confounding factors. Here we used an experimental playback study to isolate the impacts of noise from industrial activity (natural gas drilling and road noise) on glucocorticoid levels in greater sage-grouse (Centrocercus urophasianus), a species of conservation concern. We non-invasively measured immunoreactive corticosterone metabolites from fecal samples (FCMs) of males on both noise-treated and control leks (display grounds) in two breeding seasons. We found strong support for an impact of noise playback on stress levels, with 16.7% higher mean FCM levels in samples from noise leks compared with samples from paired control leks. Taken together with results from a previous study finding declines in male lek attendance in response to noise playbacks, these results suggest that chronic noise pollution can cause greater sage-grouse to avoid otherwise suitable habitat, and can cause elevated stress levels in the birds who remain in noisy areas. AuthorsBlickley, Jessica L.; Word, Karen R.; Krakauer, Alan H.; Phillips, Jennifer L.; Sells, Sarah N.; Taff, Conor C.; Wingfield, John C.; Patricelli, Gail L. Year Published2012 PublicationPLOS One LocationsDOI10.1371/journal.pone.0050462 |
| Seasonal reproductive costs contribute to reduced survival of female greater sage-grouse | Blomberg, Erik J. | 2013 |
KeywordsNo keywords available AbstractTradeoffs among demographic traits are a central component of life history theory. We investigated tradeoffs between reproductive effort and survival in female greater sage-grouse breeding in the American Great Basin, while also considering reproductive heterogeneity by examining covariance among current and future reproductive success. We analyzed survival and reproductive histories from 328 individual female greater sage-grouse captured between 2003 and 2011, and examined the effect of reproductive effort on survival and future reproduction. Monthly survival of females was variable within years, and this within-year variation was associated with distinct biological seasons. Monthly survival was greatest during the winter (NovemberMarch; phi W= 0.99 +/- 0.001 SE), and summer (JuneJuly; phi S= 0.98 +/- 0.01 SE), and lower during nesting (AprilMay; phi N= 0.93 +/- 0.02 SE) and fall (AugustOctober; phi F= 0.92 +/- 0.02 SE). Successful reproduction was associated with reduced monthly survival during summer and fall, and this effect was greatest during fall. Females that successfully fledged chicks had lower annual survival (0.47 +/- 0.05 SE) than females who were not successful (0.64 +/- 0.04 SE). Annual survival did not vary across years, consistent with a slow-paced life history strategy in greater sage-grouse. In contrast, reproductive success varied widely, and was positively correlated with annual rainfall. We found evidence for heterogeneity among females with respect to reproductive success; compared with unsuccessful females, females that raised a brood successfully in year t were more than twice as likely to be successful in year t+ 1. Female greater sage-grouse incur costs to survival associated with reproduction, however, variation in quality among females may override costs to subsequent reproductive output. AuthorsBlomberg, Erik J.; Sedinger, James S.; Nonne, Daniel V.; Atamian, Michael T. Year Published2013 PublicationJournal of Avian Biology LocationsDOI10.1111/j.1600-048X.2012.00013.x |
| Effects of Organophosphorus Insecticides on Sage Grouse in Southeastern Idaho | BLUS, LJ | 1989 |
KeywordsNo keywords available AbstractDie-offs of sage grouse (Centrocercus urophasianus) were verified in southeastern Idaho in 1981.
We captured 82 apparently healthy grouse to quantify the effects of organophosphorus insecticides (OP's)
and other pesticides on sage grouse in sagebrush (Artemisia spp.) bordering agricultural lands in July 1985 and 1986. Grouse were fitted with radio collars and tracked through part of each summer. At least 18% of 82 radio-tagged grouse in 1985-86 subsequently occupied fields at the time they were sprayed with OP
insecticides dimethoate or methamidophos. Cholinesterase (ChE) assays of brains and residue analysis of crop contents indicated that 5 and 16% of the marked sample died from OP's in 1985 and 1986, respectively. Approximately 200 sage grouse were present in a block of alfalfa sprayed with dimethoate; 63 of these were later found dead and ChE activity in 43 brains suitable for assay were depressed >50%. Maximum residues in crop contents of dead grouse were 18 Ag/g methamidophos and 30 g/g dimethoate. Intoxicated or dead grouse were observed in or near 6 fields sprayed with dimethoate or methamidophos in 1985-86. Twenty of 31 intoxicated grouse radiotagged after being found in dimethoate-sprayed (1986) alfalfa died. Our study indicates that certain pesticides have the potential for adversely affecting grouse populations. AuthorsBLUS, LJ; STALEY, CS; HENNY, CJ; PENDLETON, GW; CRAIG, TH; CRAIG, EH; HALFORD, DK Year Published1989 PublicationThe Journal of Wildlife Management LocationsDOI10.2307/3809623 |
| EFFICACY OF TWO VARIATIONS ON AN AERIAL LEK-COUNT METHOD FOR GREATER SAGE-GROUSE | Booth, D. T. | 2009 |
Keywordsaerial approach, aerial photography, behavior, Centrocercus urophasianus, crouching, flushing, overflight, Greater Sage-Grouse AbstractGreater Sage-Grouse (Centrocercus urophasianus) is a species of concern, and accurate population data are needed to monitor conservation management efforts. Conventional, ground-based lek counts are labor-intensive, expensive, and have several sources of potential error and bias, including the practical limits on number and distribution of leks counted. We tested aerial methods for photographing Multiple leks during a single morning. We completed 14 aerial approaches to 6 leks in 2 different years using 2 different airplanes and altitudes. Grouse flushed from leks on 12 approaches when the airplane was within 200-300 m of the lek. In 2 instances, strutting grouse crouched and stayed on the lek. Our highest-resolution images increased our confidence in grouse identification but also decreased field-of-view coverage to the detriment of count accuracy The methods we tested do not allow sage-grouse to be accurately Counted, but the results provide information about sage-grouse responses to low-altitude airplane approaches and about useful image resolutions and fields of view AuthorsBooth, D. T.; Cox, S. E.; Simonds, G. E.; Elmore, B. Year Published2009 PublicationWestern North American Naturalist LocationsDOI10.3398/064.069.0319 |
| THE RED QUEEN VISITS SAGE GROUSE LEKS | BOYCE, MS | 1990 |
THE RED QUEEN VISITS SAGE GROUSE LEKSKeywordsNo keywords available AbstractNo abstract available AuthorsBOYCE, MS Year Published1990 PublicationAmerican Zoologist Locations |
| The influence of gap size on sagebrush cover estimates with the use of line intercept technique | Boyd, Chad S. | 2007 |
KeywordsVegetation inventory, wildlife habitat, sage-grouse, sagebrush obligate AbstractSagebrush cover is often estimated with the use of the line intercept method. However, a lack of standardized protocols may lead to variable estimates of sagebrush canopy cover. Our objectives were to determine the influence of gap size on 1) sagebrush canopy cover estimates, 2) time needed to read a transect, and 3) among-observer variability in sagebrush canopy cover estimates. We utilized 5-, 10-, and 15-cm gaps, and defined a gap as a lack of continuous live or dead shrub canopy. In instances where a segment of dead cover was less than the gap size and adjoined live cover, the dead cover was measured as live. We evaluated canopy cover at 6 Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. Wyomingensis Beetle & A. Young) sites in southeast Oregon. At each site, four 2-person teams measured sagebrush canopy intercept along 50-m transects. Each transect was read by multiple teams to allow for assessment of among-observer variability. Intercept values were converted to percent canopy cover and we used analysis of variance to determine the influence of site and gap size on measurement time and cover estimates. Observer variability was highest at the intermediate gap size (i.e., 10 cm). Transect measurement time was longest with the use of a 5-cm gap (P < 0.001). Total cover estimates were not related to gap size (P = 0.270). Live canopy cover estimates increased (P < 0.001) from 12.1% to 14.5% with increasing gap size, and cover of dead material decreased (P = 0.015) from 4.4% to 3.2%. These differences are small in magnitude and would not likely change a gross assessment of vegetation status. However, use of a standardized gap size will enhance comparability of canopy cover estimates among studies and will decrease between-year sampling error for repeat monitoring. AuthorsBoyd, Chad S.; Bates, Jon D.; Miller, Rick F. Year Published2007 PublicationRangeland Ecology & Management LocationsDOI10.2111/05-226R2.1 |
| How predation risk affects the temporal dynamics of avian leks: Greater sage grouse versus golden eagles | Boyko, AR | 2004 |
Keywordslek mating system, dynamic game theory, greater sage grouse, mating skew, density dependence, predation AbstractLeks often attract predators as well as mates, yet most evolutionary models have assumed that sexual selection, not predation, drives lekking behavior. We explored the influence of predation on lek dynamics using a stochastic dynamic game model based on the lek-breeding greater sage grouse (Centrocercus urophasianus) and its principal avian predator, the golden eagle (Aquila chrysaetos). The model predicts time-dependent male lek attendance as a function of factors affecting both mating success (female arrival rate, male numbers, and social status) and predation risk (eagle arrival rate and group size). Dominant males are predicted to arrive sooner and leave later than subordinates, especially if mating skew is high, predation risk is low, or the relationship between lek size and female arrival rate is weak. Both high mean levels of predation risk and small lek size should reduce lek attendance, but the relative tendency of predators to attack large versus small leks has little influence on predicted lekking behavior. Field observations confirmed the predicted effects of female arrival rate, lek size, male dominance, and weather-dependent predator arrival rates on lek departure times. Predicted effects of female arrival rates and male dominance on seasonal lek attendance were also supported. Our model provides an empirically supported adaptive explanation for short-term lek dynamics. It also suggests alternative interpretations for phenomena previously invoked to support the hotshot and skew models of lek formation. AuthorsBoyko, AR; Gibson, RM; Lucas, JR Year Published2004 PublicationAmerican Naturalist LocationsDOI10.1086/380419 |
| Dispersion of displaying male sage grouse | BRADBURY, JW | 1989 |
KeywordsNo keywords available AbstractThe degree to which male sage grouse select lek sites and females select nesting sites to maximize proximity to the other sex was examined by contrasting male dispersions with the dispersions and movements of females in the months preceeding incubation. Wintering females exhibit highly overlapping ranges due to shared use of central refuging areas. In late winter and early spring, females move an average 9 km from wintering areas to select nest sites and males begin occupying leks. Pooled evidence suggests that females select nest sites independently of male dispersion whereas males adjust lek occupation so as to maximize proximity to females. Relevant observations include females visiting nest sites before leks, moving further to select a nest site than to select a lek, and increasing their distance to leks as a result of selecting nest sites. In addition, males avoid leks until females have moved to within 5 km of the arenas, abandon early season leks as local female densities drop, and exhibit dispersions in which mean ratios of females/male are similar across leks. Contrasts between predicted and observed dispersions of males showed that hotspot settlement models are adequate to explain male dispersions on very coarse scales (2 km or greater); on finer scales, habitat preferences of males and tendencies for males to cluster tightly must be invoked in addition to hotspots to explain specific lek sitings. AuthorsBRADBURY, JW; GIBSON, RM; MCCARTHY, CE; VEHRENCAMP, SL Year Published1989 PublicationBehavioral Ecology And Sociobiology LocationsDOI10.1007/BF00300113 |
| DISPERSION OF DISPLAYING MALE SAGE GROUSE .1. PATTERNS OF TEMPORAL VARIATION | BRADBURY, JW | 1989 |
DISPERSION OF DISPLAYING MALE SAGE GROUSE .1. PATTERNS OF TEMPORAL VARIATIONKeywordsNo keywords available AbstractNo abstract available AuthorsBRADBURY, JW; VEHRENCAMP, SL; GIBSON, RM Year Published1989 PublicationBehavioral Ecology And Sociobiology Locations |
