Innovative approaches for development of conservation plans for sage grouse: examples from Idaho and Colorado. | Hemker, Thomas P. | 2001 |
Innovative approaches for development of conservation plans for sage grouse: examples from Idaho and Colorado.KeywordsNo keywords available AbstractNo abstract available AuthorsHemker, Thomas P.; Braun, Clait E. Year Published2001 PublicationTransactions of The North American Wildlife And Natural Resources Conference Locations |
Spatial patterns of population regulation in sage grouse (Centrocercus spp.) population viability analysis | La Montagne, JM | 2002 |
KeywordsAICc; population dynamics; spatial correlation Abstract1. Population viability analyses (PVAs) are commonly used to identify species of concern. Many PVA techniques assume that all populations are regulated by a single mechanism.2. We compared population viability predictions for three subspecies of sage grouse (Centrocercus spp.) based on the assumptions that: (i) population regulation was density-independent vs. dependent on more complex feedback mechanisms; (ii) the mechanism of population regulation was homogeneous within a region vs. heterogeneous among leks; (iii) environmental variation was spatially correlated within regions vs. uncorrelated among leks.3. We used sage grouse as a model species for this analysis because counts of lekking male grouse are available in some areas since the 1950s, these counts are known to fluctuate widely, and sage grouse appear to be declining throughout their range.4. We fit population regulation models to data including density-independence, density-dependence, delayed density-dependence and a simplified version of Turchin & Taylor's (1992) response surface model.5. We show that the best-fit models typically include spatial heterogeneity in mechanisms of population regulation. Inclusion of spatial heterogeneity increased expected time for population persistence, and changed the rank order of risk of extinction for different regions.6. We suggest that it is important to consider multiple models of population regulation when applying population viability analysis techniques because viability projections are influenced strongly by model structure. AuthorsLa Montagne, JM; Irvine, RL; Crone, EE Year Published2002 PublicationJournal of Animal Ecology LocationsDOI10.1046/j.1365-2656.2002.00629.x |
Modeled Effects of Sagebrush-Steppe Restoration on Greater Sage-Grouse in the Interior Columbia Basin, U.S.A. | Wisdom, MJ | 2002 |
KeywordsNo keywords available AbstractHabitats of Greater Sage-Grouse (Centrocercus urophasianus) have declined across western North America, and most remaining habitats occur on lands administered by the U.S. Forest Service (FS) and U.S. Bureau of Land Management (BLM). Consequently, managers of FS-BLM lands need effective strategies to recover sagebrush (Artemisia spp.) habitats on which this species depends. In response to this need, we evaluated the potential benefits of two restoration scenarios on Greater Sage-Grouse in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States. Scenario 1 assumed a 50% reduction in detrimental grazing effects (through changes in stocking rates and grazing systems) and a six-fold increase in areas treated with active restoration (e.g., prescribed burning, native seedings, wildfire suppression) compared with future management proposed by the FS-BLM. Scenario 2 assumed a 100% reduction in detrimental grazing effects and the same increase in active restoration as scenario 1. To evaluate benefits, we estimated the risk of population extirpation for sage grouse 100 years in the future under the two scenarios and compared this risk with that estimated for proposed (100-year) FS-BLM management. We used estimates of extirpation risk for historical (circa 1850-1890) and current time periods as a context for our comparison. Under historical conditions, risk of extirpation was very low on FS-BLM lands, but increased to a moderate probability under current conditions. Under proposed FS-BLM management, risk of extirpation on FS-BLM lands increased to a high probability 100 years in the future. Benefits of the two restoration scenarios, however, constrained the future risk of extirpation to a moderate probability. Our results suggest that expansive and sustained habitat restoration can maintain desired conditions and reduce future extirpation risk for sage grouse on FS-BLM lands in western North America. The continued spread of exotic plants, however, presents a formidable challenge to successful restoration and warrants substantial research and management attention. AuthorsWisdom, MJ; Rowland, MM; Wales, BC; Hemstrom, MA; Hann, WJ; Raphael, MG; Holthausen, RS; Gravenmier, RA; Rich, TD Year Published2002 PublicationConservation Biology LocationsDOI10.1046/j.1523-1739.2002.01073.x |
Performance of Greater Sage-Grouse Models for Conservation Assessment in the Interior Columbia Basin, U.S.A. | Wisdom, MJ | 2002 |
KeywordsNo keywords available AbstractValid modeling of habitats and populations of Greater Sage-Grouse (Centrocercus urophasianus ) is a critical management need because of increasing concern about population viability. Consequently, we evaluated the performance of two models designed to assess landscape conditions for Greater Sage-Grouse across 13.6 million ha of sagebrush steppe in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States (referred to as the basin). The first model, the environmental index model, predicted conditions at the scale of the subwatershed (mean size of approximately 7800 ha) based on inputs of habitat density, habitat quality, and effects of human disturbance. Predictions ranged on a continuous scale from 0 for lowest environmental index to 2 for optimal environmental index. The second model, the population outcome model, predicted the composite, range-wide conditions for sage grouse based on the contribution of environmental index values from all subwatersheds and measures of range extent and connectivity. Population outcomes were expressed as five classes (A through E) that represented a gradient from continuous, well-distributed populations (outcome A) to sparse, highly isolated populations with a high likelihood of extirpation (outcome E). To evaluate performance, we predicted environmental index values and population outcome classes in areas currently occupied by sage grouse versus areas where extirpation has occurred. Our a priori expectations were that models should predict substantially worse environmental conditions (lower environmental index) and a substantially higher probability of extirpation (lower population outcome class) in extirpated areas. Results for both models met these expectations. For example, a population outcome of class E was predicted for extirpated areas, as opposed to class C for occupied areas. These results suggest that our models provided reliable landscape predictions for the conditions tested. This finding is important for conservation planning in the basin, where the models were used to evaluate management of federal lands for sage grouse. AuthorsWisdom, MJ; Wales, BC; Rowland, MM; Raphael, MG; Holthausen, RS; Rich, TD; Saab, VA Year Published2002 PublicationConservation Biology LocationsDOI10.1046/j.1523-1739.2002.01074.x |
Sagebrush-Steppe Vegetation Dynamics and Restoration Potential in the Interior Columbia Basin, U.S.A. | Hemstrom, MA | 2002 |
KeywordsNo keywords available AbstractWe modeled the dynamics and restoration of sagebrush (Artemisia spp.) habitats for Greater Sage-Grouse (Centrocercus urophasianus) in the interior Columbia Basin and adjacent portions of the Great Basin (referred to as the basin). Greater Sage-Grouse have undergone widespread decline and are the focus of conservation on over 13 million ha of sagebrush steppe in the basin, much of which is managed by the U.S. Forest Service (FS) and U.S. Bureau of Land Management (BLM ). Consequently, we evaluated changes in the amount and quality of sage-grouse habitat on 8.1 million ha of FS-BLM lands in the basin. Changes were estimated from historical to current conditions and from current conditions to those projected 100 years in the future under proposed management and under two restoration scenarios. These two scenarios were designed to improve long-term (100-year) projections of sage-grouse habitat on FS-BLM lands in relation to current conditions and proposed management. Scenario 1 assumed a 50% reduction in detrimental grazing effects by livestock (through changes in stocking rates and grazing systems) and a six-fold increase in areas treated with active restoration relative to proposed management. Scenario 2 assumed a 100% reduction in detrimental grazing effects and the same level of active restoration as scenario 1. Under the two scenarios, the amount of FS-BLM habitat for sage grouse within treated areas declined by 17-19% 100 years in the future compared with the current period, but was 10-14% higher than the 100-year projection under proposed management. Habitat quality under both scenarios was substantially improved compared with the current period and proposed management. Our results suggest that aggressive restoration could slow the rate of sagebrush loss and improve the quality of remaining habitat. AuthorsHemstrom, MA; Wisdom, MJ; Hann, WJ; Rowland, MM; Wales, BC; Gravenmier, RA Year Published2002 PublicationConservation Biology LocationsDOI10.1046/j.1523-1739.2002.01075.x |
Predation on real and artificial nests in shrubsteppe landscapes fragmented by agriculture | Haegen, WMV | 2002 |
Keywordsartificial nests, cameras, grouse, nest predators, nest success, passerines, shrubsteppe AbstractClearing of shrubsteppe communities for agriculture has created a highly fragmented landscape in eastern Washington, a condition that has been shown to adversely affect nesting success of birds in some forest and grassland communities. We used artificial nests monitored by cameras to examine relative effects of fragmentation, distance to edge, and vegetation cover on nest predation rates and to identify predators of shrubsteppenesting passerines and grouse. Predation rate for artificial nests was 26% (n = 118). Fragmentation had a strong influence on predation rates for artificial nests, with nests in fragmented landscapes about 9 times more likely to be depredated as those in continuous landscapes. Daily survival rate (+/- SE) for 207 real nests of 4 passerine species also was greater in continuous (0.978 +/- 0.004) than in fragmented (0.962 +/- 0.006) landscapes, although pattern of predation between real and artificial nests was not consistent among sites. Artificial nests were depredated by Common Ravens (Corvus corax), Black-billed Magpies (Pica hudsonia), Sage Thrashers (Oreoscoptes montanus), least chipmunks (Tamias minimus), and mice. Most nests in fragments were depredated by corvids (58%), whereas only Sage Thrashers and small mammals depredated nests in continuous landscapes. Increased predation by corvids and lower nest success in fragmented landscapes may have played a part in recent declines of some shrubsteppe birds. Future research should measure annual reproductive success of individual females and survival rates of juveniles and adults. AuthorsHaegen, WMV; Schroeder, MA; DeGraaf, RM Year Published2002 PublicationThe Condor: Ornithological Applications LocationsDOI10.1650/0010-5422(2002)104%5B0496:PORAAN%5D2.0.CO;2 |
Sage-Grouse Nesting and Brood Habitat Use in Southern Canada | Aldridge, CL | 2002 |
KeywordsNo keywords available AbstractGreater sage-grouse (Centrocercus urophasianus) populations have declined from 66 to 92% during the last 30 years in Canada, where they are listed as endangered. We used radiotelemetry to examine greater sage-grouse nest and brood habitat use in Alberta and assess the relationship between habitat and the population decline. We also identified the patch size at which sage-grouse were selecting nest and brood-rearing sites. Nest areas were in silver sagebrush (Artemisia cana) stands that had greater amounts of tall cover (P less than or equal to 0.001) at a patch size of 7.5 to 15 m in radius. Within those sagebrush stands, nests were located beneath the densest sagebrush present. Areas used for brood rearing had greater amounts of taller sagebrush cover in an area : 15 m in radius than at random locations. Brood locations were not selected based on forb content; mesic areas containing forbs (20-40% cover) as a food resource for chicks were limiting (only 12% cover available). Overall cover of sagebrush is considerably lower in Canada (5-11%) compared with sagebrush (Artemisia spp.) cover in other areas throughout the range of greater sage-grouse (15-25%). If management goals are to provide suitable nesting and brood-rearing habitat, efforts should be directed toward protecting and enhancing sagebrush stands greater than or equal to30 m(2) and increasing overall sagebrush cover. Management strategies also should focus on increasing the availability of mesic sites and increasing the abundance of sites with >10% forb cover, to enhance brood rearing habitat. AuthorsAldridge, CL; Brigham, RM Year Published2002 PublicationThe Journal of Wildlife Management LocationsDOI10.2307/3803176 |
Altered rangeland ecosystems in the interior Columbia basin. | Bunting, Stephen C. | 2002 |
Altered rangeland ecosystems in the interior Columbia basin.KeywordsNo keywords available AbstractA workshop was held to address specific questions related to altered rangeland ecosystems within the interior Columbia basin. Focus was primarily on public lands administered by the Forest Service and Bureau of Land Management. Altered ecosystems were considered to be those where human-induced or natural disturbances are of sufficient magnitude to affect ecosystem processes, causing long-term loss or displacement of native community types and loss of productivity, making it difficult or impossible to restore these ecosystems to historical conditions. Seventeen rangeland potential vegetation types (PVT) were identified by the Interior Columbia Basin Ecosystem Management Project and briefly described. Reasons that rangeland ecosystems are altered include presence of invasive species, uncharacteristic grazing effects, climatic change, change in fire regime, and other factors related to human presence. However, primary causes of alteration and restoration potential differ among PVTs. Some altered rangeland ecosystems may be restored by stabilizing ecosystem processes, restoring native plant communities, reducing the spread of invasive species, or conserving existing biota. In some altered conditions, these options have a relatively high probability of success over the short term with low to moderate cost at the site scale. However, in other altered areas, restoration options are expensive, have a low probability of success, and require long timeframes. Restoration of rangeland PVTs is also necessary for the survival of some animal species whose populations are in decline such as the Columbian sharp-tailed grouse and greater sage grouse. AuthorsBunting, Stephen C.; Kingery, James L.; Hemstrom, Miles A.; Schroeder, Michael A.; Gravenmier, Rebecca A.; Hann, Wendel J. Year Published2002 PublicationU S Forest Service Pacific Northwest Research Station General Technical Report Locations |
Attachment of radiotransmitters to one-day-old sage grouse chicks | Burkepile, NA | 2002 |
Attachment of radiotransmitters to one-day-old sage grouse chicksKeywordsCentrocercus urophasianus, chicks, radiotransmitters, sage grouse, telemetry AbstractOur understanding of cause- and age-specific mortality in sage grouse (Centrocercus urophasianus) chicks is limited due to their cryptic and secretive nature. Recent improvements in radiotransmitters have enhanced our ability to monitor sage grouse chicks as young as one day old. We describe a suturing method to attach radiotransmitters to one-day-old sage grouse chicks. During springs of 1999 and 2000, we attached radiotransmitters to 75 chicks from 28 broods and monitored them daily. Radiotransmitter retention rates were high, and there was no sign of infection on recaptured chicks. Using suturing to attach radiotransmitters is an effective means to collect ecological data on sage grouse chicks. AuthorsBurkepile, NA; Connelly, JW; Stanley, DW; Reese, KP Year Published2002 PublicationWildlife Society Bulletin Locations |
Oil and gas development in western North America: effects on sagebrush steppe avifauna with particular emphasis on sage grouse. | Braun, Clait E. | 2002 |
Oil and gas development in western North America: effects on sagebrush steppe avifauna with particular emphasis on sage grouse.KeywordsNo keywords available AbstractNo abstract available AuthorsBraun, Clait E.; Oedekoven, Olin O.; Aldridge, Cameron L. Year Published2002 PublicationTransactions of The North American Wildlife And Natural Resources Conference Locations- Alberta, Canada (49.4, -110.702)
- Jackson county, Colorado (40.6667, -106.333)
- Moffat county, Colorado (40.65, -108.083)
- Rio Blanco county, Colorado (39.95, -108.2)
- Routt county, Colorado (40.5167, -106.983)
- northeastern Wyoming (44.4, -105.8)
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