| FACTORS CONTRIBUTING TO PROCESS VARIANCE IN ANNUAL SURVIVAL OF FEMALE GREATER SAGE-GROUSE IN MONTANA | Moynahan, Brendan J. | 2006 |
Keywordsbreeding status vs. survival;Centrocercus urophasianus;Greater Sage-Grouse;habitat protection;known fate;Montana, USA;population dynamics;process variance;program MARK;sagebrush;survival estimation;winter weather AbstractPopulations of Greater Sage-Grouse (Centrocercus urophasianus) have declined by 69–99% from historic levels, and information on population dynamics of these birds at a landscape scale is essential to informed management. We examined the relationships between hen survival and a suite of landscape-scale habitat and environmental conditions. We radio-marked 237 female Sage-Grouse and measured 426 vegetation plots during 2001–2004 at four sites in a 3200-km2 landscape in north-central Montana, USA. We used program MARK to model monthly survival rates for 11 seasonal intervals. There was strong support for the best-approximating model (AICc weight = 0.810), which indicated that (1) hen survival varied by season within years and by year within seasons, (2) nesting hens had higher nesting-season survival than non-nesting hens, and (3) individuals at one site had lower hunting-season survival than at other sites. We observed considerable variation in hen survival. Process variation was 0.255, with an expected range of annual survival of 0.12 to 1.0. The ratio of process to total variation was 0.999, indicating that observed variation was real and not attributable to sampling variation. We observed a nearly fourfold difference in maximum and minimum annual survival, ranging from 0.962 ± 0.024 (mean ± se) for nesting hens in 2001–2002 to 0.247 ± 0.050) for non-nesters in 2003–2004. Low annual survival in 2003 resulted from the compounded effects of a West Nile virus outbreak in August and a severe winter in 2003–2004. Increased hen mortality associated with severe winter weather contrasts with prior beliefs that Sage-Grouse populations are typically unaffected by winter weather conditions and underscores the importance of protecting winter sagebrush (Artemisia spp.) habitats. AuthorsMoynahan, Brendan J., Mark S. Lindberg, and Jack Ward Thomas. Year Published2006 PublicationEcological Applications LocationsDOI10.1890/1051-0761(2006)016[1529:FCTPVI]2.0.CO;2 This article contributed by:Ecological Society of America |
| West Nile virus: pending crisis for greater sage-grouse | Naugle, DE | 2004 |
KeywordsCentrocercus urophasianus, emerging infectious disease, endangered species; greater sage-grouse; mosquito; population decline; survival; vector surveillance; West Nile virus AbstractScientists have feared that emerging infectious diseases could complicate efforts to conserve rare and endangered species, but quantifying impacts has proven difficult until now. We report unexpected impacts of West Nile virus (WNv) on radio-marked greater sage-grouse (Centrocercus urophasianus), a species that has declined 45-80% and is endangered in Canada and under current consideration for federal listing in the US. We show that WNv reduced late-summer survival an average of 25% in four radio-marked populations in the western US and Canada. Serum from 112 sage-grouse collected after the outbreak show that none had antibodies, suggesting that they lack resistance. The spread of WNv represents a significant new stressor on sage-grouse and probably other at-risk species. While managing habitat might lessen its impact on sage-grouse populations, WNv has left wildlife and public health officials scrambling to address surface water and vector control issues in western North America. AuthorsNaugle, DE; Aldridge, CL; Walker, BL; Cornish, TE; Moynahan, BJ; Holloran, MJ; Brown, K; Johnson, GD; Schmidtmann, ET; Mayer, RT; Kato, CY; Matchett, MR; Christiansen, TJ; Cook, WE; Creekmore, T; Falise, RD; Rinkes, ET; Boyce, MS Year Published2004 PublicationEcology Letters LocationsDOI10.1111/j.1461-0248.2004.00631.x |
| Parasites and Infectious Diseases of Greater Sage-Grouse. | Christiansen, Thomas J. | 2011 |
KeywordsCentrocercus urophasianus, disease, greater sage-grouse, parasite, pathogen AbstractWe report the parasites, infectious diseases, and noninfectious diseases related to toxicants found in Greater Sage-Grouse (Centrocercus urophasianus) across its range. Documentation of population-level effects is rare, although researchers have responded to the recent emergence of West Nile virus with rigorous efforts. West Nile virus shows greater virulence and potential population-level effects than any infectious agent detected in Greater Sage-Grouse to date. Research has demonstrated that (1) parasites and diseases can have population-level effects on grouse species; (2) new infectious diseases are emerging; and (3) habitat fragmentation is increasing the number of small, isolated populations of Greater Sage-Grouse. Natural resource management agencies need to develop additional research and systematic monitoring programs for evaluating the role of micro-and macro parasites, especially West Nile virus, infectious bronchitis and other corona viruses, avian retroviruses, Mycoplasma spp., and Eimeria spp. and associated enteric bacteria affecting sage-grouse populations. AuthorsChristiansen, Thomas J.; Tate, Cynthia M. Year Published2011 PublicationStudies in Avian Biology LocationsDOI10.1525/california/9780520267114.001.0001 |
| West Nile Virus and Greater Sage-Grouse: Estimating Infection Rate in a Wild Bird Population | Walker, Brett L. | 2007 |
KeywordsCentrocercus urophasianus, coal-bed natural gas, energy development, flavivirus, greater sage-grouse, infection rate, sagebrush-steppe, West Nile virus AbstractUnderstanding impacts of disease on wild bird populations requires knowing not only mortality rate following infection, but also the proportion of the population that is infected. Greater sage-grouse (Centrocercus urophasianus) in western North America are known to have a high mortality rate following infection with West Nile virus (WNv), but actual infection rates in wild populations remain unknown. We used rates of WNv-related mortality and seroprevalence from radiomarked females to estimate infection rates in a wild greater sage-grouse population in the Powder River basin (PRB) of Montana and Wyoming from 2003 to 2005. Minimum WNv-related mortality rates ranged from 2.4% to 13.3% among years and maximum possible rates ranged from 8.2% to 28.9%. All live-captured birds in 2003 and 2004 tested seronegative. In spring 2005 and spring 2006, 10.3% and 1.8% respectively, of newly captured females tested seropositive for neutralizing antibodies to WNv. These are the first documented cases of sage-grouse surviving infection with WNv. Low to moderate WNv-related mortality in summer followed by low seroprevalence the following spring in all years indicates that annual infection rates were between 4% and 29%. This suggests that most sage-grouse in the PRB have not yet been exposed and remain susceptible. Impacts of WNv in the PRB in the near future will likely depend more on annual variation in temperature and changes in vector distribution than on the spread of resistance. Until the epizootiology of WNv in sagebrush-steppe ecosystems is better understood, we suggest that management to reduce impacts of WNv focus on eliminating man-made water sources that support breeding mosquitoes known to vector the virus. Our findings also underscore problems with using seroprevalence as a surrogate for infection rate and for identifying competent hosts in highly susceptible species. AuthorsWalker, Brett L.; Naugle, David E.; Doherty, Kevin E.; Cornish, Todd E. Year Published2007 PublicationAvian Diseases LocationsDOI10.1637/0005-2086(2007)51[691:WNVAGS]2.0.CO;2 |
| 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 |
| Husbandry of wild-caught greater sage-grouse | Oesterle, P | 2005 |
KeywordsArtemisia, Centrocercus urophasianus, husbandry, sage-grouse, West Nile virus AbstractThis study reports the first successful husbandry and breeding in captivity of wild-caught greater sage-grouse (Centrocercus urophasianus). In October 2003, 21 hatch-year greater sage-grouse were trapped in northwestern Nevada and transported to Fort Collins, Colorado. We held grouse in pens at the United States Department of Agriculture's National Wildlife Research Center for 8 months. We offered a varied diet, including native food items such as sagebrush (Artemisia tridentata and A. tripartita) and yarrow (Achillea millefolium). We housed grouse in a large flight pen and allowed to them free-range as one flock. Mortality rate was 16.7%. Several of the grouse exhibited breeding behavior, and 13 eggs were laid. We describe the techniques used to house and feed wild-caught sage-grouse. This study has conservation implications for captive breeding of this species of concern. AuthorsOesterle, P; McLean, R; Dunbar, M; Clark, L Year Published2005 PublicationWildlife Society Bulletin LocationsDOI10.2193/0091-7648(2005)33[1055:HOWGS]2.0.CO;2 |
| West Nile virus and sage-grouse: What more have we learned? | Naugle, DE | 2005 |
KeywordsCentrocercus urophasianus; emerging infectious disease; monitoring; population decline; sage-grouse; survival; West Nile virus AbstractWest Nile virus (WNv) has emerged as a new issue in the conservation of native avifauna in North America. Mortality associated with WNv infection decreased survival of female greater sage-grouse (Centrocercus urophasianus) by 25% across 4 populations in Wyoming and Montana, USA, and Alberta, Canada, in 2003. In 2004 WNv spread to populations in Colorado and California, and female survival in late summer was 10% lower at 4 sites with confirmed WNv mortalities (86% survival) than at 8 sites without (96%). We still have no evidence that sage-grouse show resistance to the virus. The 2004 WNv season was not the catastrophe that many had predicted, and the decrease in prevalence of infection and mortality in sage-grouse, humans, and horses (except in California) has left many wondering if the worst has past. Evidence suggests that risk of infection was low in 2004 because unseasonably cool summer temperatures delayed or reduced mosquito production. Moreover, mortalities occurred 2-3 weeks later in 2004 than in 2003, and the shift to later timing was consistent between years at sites where WNv reduced survival both years. Mosquito surveillance data indicated a sharp decline in prevalence and infection rate of adult C. tarsalis in southeast Alberta, the most northern latitude where WNv reduced survival, in 2003 but not in 2004. A full understanding of the implications of WNv for sage-grouse requires a long-term, coordinated monitoring strategy among researchers and a sensitivity analysis to evaluate the role of WNv in population viability. Epidemiological research examining the prevalence and ecology of the virus among reservoir hosts is crucial. AuthorsNaugle, DE; Aldridge, CL; Walker, BL; Doherty, KE; Matchett, MR; McIntosh, J; Cornish, TE; Boyce, MS Year Published2005 PublicationWildlife Society Bulletin Locations- Alberta, Canada (49.4, -110.702)
- Phillips County, Montana (48.2, -107.933)
- Central Washington (46.779, -119.486)
- Roundup, Montana (46.4453, -108.541)
- Southern Powder River Basin, Wyoming (44.3442, -106.293)
- Lander, Wyoming (42.8331, -108.73)
- Upper Green River Basin, Wyoming (42.742, -109.869)
- Routt County, Colorado (40.5167, -106.983)
- Moffat County, Colorado. Axial Basin 40 km southwest of Craig, Colorado. (40.2602, -107.881)
- Gunnison County Colorado (38.7, -107.067)
- Mono County, California (37.9167, -118.867)
DOI10.2193/0091-7648(2005)33[616:WNVASW]2.0.CO;2 |
| Liver metal concentrations in Greater Sage-grouse (Centrocercus urophasianus) | Dailey, Rebecca N. | 2008 |
Liver metal concentrations in Greater Sage-grouse (Centrocercus urophasianus)KeywordsCentrocercus urophasianus, ICP-MS, liver, metals, sage-grouse AbstractGreater Sage-grouse (Centrocercus urophasianus) are a species of concern due to shrinking populations associated with habitat fragmentation and loss. Baseline health parameters for this species are limited or lacking, especially with regard to tissue metal concentrations. To obtain a range of tissue metal concentrations, livers were collected from 71 Greater Sage-grouse from Wyoming and Montana. Mean SE metal concentrations (mg/kg wet weight) in liver were determined for vanadium (V) (0.12 +/- 0.01), chromium (Cr) (0.50 +/- 0.02), manganese (Mn) (2.68 +/- 0.11), iron (Fe) (1,019 +/- 103), nickel (Ni) (0.40 +/- 0.04), cobalt (Co) (0.08 +/- 0.02), copper (Cu) (6.43 +/- 0.40), mercury (Hg) (0.30 +/- 0.09), selenium (Se) (1.45 +/- 0.64), zinc (Zn) (59.2 +/- 4.70), molybdenum (Mo) (0.93 +/- 0.07), cadmium (Cd) (1.44 +/- 0.14), barium (Ba) (0.20 +/- 0.03), and lead (Pb) (0.17 +/- 0.03). In addition to providing baseline data, metal concentrations were compared between sex, age (juvenile/adult), and West Nile virus (WNv) groups (positive/negative). Adult birds had higher concentrations of Ni and Cd compared to juveniles. In addition, Zn and Cu concentrations were significantly elevated in WNv-positive birds. AuthorsDailey, Rebecca N.; Raisbeck, Merl F.; Slemion, Roger S.; Cornish, Todd E. Year Published2008 PublicationJournal of Wildlife Diseases Locations |
| Susceptibility of greater sage-grouse to experimental infection with West Nile virus | Clark, L | 2006 |
Susceptibility of greater sage-grouse to experimental infection with West Nile virusKeywordsCentrocercus urophasianus
experimental infection
greater sage-grouse
vaccine
West Nile virus AbstractPopulations of greater sage-grouse (Centrocercus urophasianus) have declined 45-80% in North America since 1950. Although much of this decline has been attributed to habitat loss, recent field studies have indicated that West Nile virus (WNV) has had a significant negative impact on local populations of grouse. We confirm the susceptibility of greater sage-grouse to WNV infection in laboratory experimental studies. Grouse were challenged by subcutaneous injection of WNV (10(3.2) plaque-forming units [PFUs]). All grouse died within 6 days of infection. The Kaplan-Meier estimate for 50% survival was 4.5 days. Mean peak viremia for nonvaccinated birds was 10(6.4) PFUs/ml (+/- 10(0.2) PFUs/ml, standard error of the mean [SEM]). Virus was shed cloacally and orally. Four of the five vaccinated grouse died, but survival tune was increased (50% survival = 9.5 days), with 1 grouse surviving to the end-point of the experiment (14 days) kith no signs of illness. Mean peak viremia for the vaccinated birds was 10(2.3) PFUs/ml (+/- 10(0.6) PFUs/ml, SEM). Two birds cleared the virus from their blood before death or euthanasia. These data emphasize the high susceptibility of greater sage-grouse to infection with WNV. AuthorsClark, L; Hall, J; McLean, R; Dunbar, M; Klenk, K; Bowen, R; Smeraski, CA Year Published2006 PublicationJournal of Wildlife Diseases Locations |
| A Live Attenuated West Nile Virus Strain as a Potential Veterinary Vaccine | LUSTIG, SHLOMO | 2000 |
KeywordsWNV AbstractThis article reviews the development of two attenuated West Nile virus (WNV) variants, WNI-25 and WNI-25A. These variants have lost the neuroinvasion trait of the parental virus. Attenuation was achieved through serial passages in mosquito cells and neutralization escape from WNV-specific monoclonal antibody. Genetic analysis reveals amino acid changes between the parental and each of the variants. The attenuated variants preserve the ability to replicate in mice and geese and to induce a protective immune response. WNI-25A was found to be a genetically stable virus. This variant was successfully used as a live vaccine to protect geese against a wild-type virulent WNV field isolate that closely resembles the WNV isolated during the 1999 New York epidemic. AuthorsLUSTIG, SHLOMO, OLSHEVSKY, UDY, BEN-NATHAN, DAVID, LACHMI, BAT-EL, MALKINSON, MERTYN, KOBILER, DAVID and HALEVY, MENACHEM Year Published2000 PublicationViral Immunology LocationsDOI10.1089/vim.2000.13.401 |
