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High nest predation rates are one of the main sources of nesting failure in passerines. Mountain meadows in the Sierra Nevada have been intensively modified, reducing meadow wetness and potentially favoring easy access for mammalian predators to reach nesting areas in the meadow interior. We conducted mammal trapping in wet and dry areas of montane meadows during May through August of 2007 and 2008 to identify the assemblage of potential mammalian nest predators and determine the relationship between activity and meadow wetness. Chipmunk (Tamias spp.) activity was primarily restricted to dry areas. Activity of Yellow-pine Chipmunks (Tamias amoenus) was >90% higher in dry versus wet areas. Deer Mice (Peromyscus maniculatus) were equally active in both site types in 2007, but declined and were only captured in wet areas in 2008. Overall activity was higher in 2007 and 2008 for both wet and dry areas (68% and 52%, respectively). Our results suggest that increasing the proportion of inundated areas in meadows may reduce small mammal activity (for instance Yellow-pine Chipmunks) and potentially reduce nest predation. [ABSTRACT FROM AUTHOR]

Great Gray Owls (Strix nebulosa) in the Sierra Nevada Mountains feed primarily on rodents, especially voles and pocket gophers. Voles have been shown to be negatively affected by cattle grazing, but effects of grazing on gophers in the Sierra Nevada Mountains are unknown. We investigated the effects of grazing on pocket gophers (Thomomys monticola and T. bottae) in 21 grazed and 21 ungrazed montane meadow sites in the central Sierra Nevada Mountains of California. Pocket gopher densities were significantly higher in grazed meadows than ungrazed meadows. Vegetation cover and height, thatch depth, and the frequency of sedge occurrence were higher in ungrazed meadows and there were negative correlations between pocket gopher densities and these vegetation variables. We suggest that potential negative effects of grazing on Great Gray Owls could be minimized by managing meadow vegetation commensurate with the habitat needs of their prey. [ABSTRACT FROM AUTHOR]

Abstract: East Shield (3658m) and Barcroft Gate (3697m) Meadows in the White Mountains of California on the Inyo National Forest were selected for a pilot baseline monitoring study over five-year intervals to determine potential effects of future climate change on the meadows. Stated as a hypothesis: given the natural range of temporal variability of meadow vegetation, a significant portion of that variability is attributed to the effects of climatic variation. The study is associated with the Global Observation Research Initiative in Alpine Environments Project (GLORIA) hosted by the University of California White Mountain Research Station. Both meadows are sedge–rush–grass wet meadows, or fens, which are sustained by surface water in the form of streams and springs. A comprehensive plant list was compiled and the plant species of each meadow were sampled by a point intercept method along two randomly placed transects. The occurrence of all species at predetermined one-meter interval sample points along the transects were recorded, percent occurrence was calculated, and descriptive statistics were done. The monitoring objective is to detect a 20% biologically meaningful change in the vegetation over time with 90% confidence, and accept a 10% chance of a false change error (Type 1 error). Monitoring is planned to be done in conjunction with tracking change in precipitation and temperature. Three indicators of possible climate change were chosen. One indicator is increase in the abundance of those species whose upper range is at or below meadow elevations. The rationale for this indicator is based the 2007 IPCC report estimation that a doubling of atmospheric CO2 will increase global temperature with a best estimate of +3.0°C. Assuming that the present general lapse rate of −6.32°C per kilometer for the White Mountains will persist, a 3.0°C increase may result in an equivalent elevation of the meadows of about +475m. Published elevation ranges indicate that most recorded species are not likely to be affected by the estimated temperature increase. Second and third indicators are a shift in cover from wet meadow to dry meadow species, and the presence and increase of shrub species resulting from postulated reduced precipitation with drying of meadows and encroachment by surrounding shrubs (sagebrush and rabbitbrush). This monitoring study has the potential to detect long-term responses of vegetation to climate change, and reduce uncertainties and confirm or correct the expected consequences of temperature change. [Copyright &y& Elsevier]

The article presents a study which examines the emergence of bats in Lake Tahoe Basin's highly impacted environment. The researchers categorized the study sties into two basic groups which include the area within the meadows and along the creeks. Several acoustic surveys were also conducted with the use of ultrasonic detectors and cassette data recorders to evaluate the richness and frequency of the bat species and occupancy. It shows that there were at least five species that occupied on creek and meadow sites, with or without the restoration of the lake.