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Montane meadows are areas of high biodiversity and provide many important ecosystem services; however, degradation of 40–60% of these habitats in the Sierra Nevada region of California has left many of these areas impaired. The "pond-and-plug" meadow-restoration technique is 1 type of treatment implemented to restore montane meadows. The objectives of this technique are to re-water the meadow and promote downstream flow by increasing the water-table elevation and providing additional water storage that will promote the growth of mesic and hydric vegetation that maintains and stabilizes stream channels. However, aquatic habitat and the composition and functioning of aquatic communities in these systems post-treatment are poorly documented or understood. We evaluated: (1) fish habitat, community composition, and relative abundance among recently created ponds spanning the range of pond habitats; (2) seasonal movement and survival of fish within and among ponds; and (3) food web structure in ponds. We documented over-summer and winter survival in the fish community and short-distance movement by 1 species occupying the ponds. Mark-recapture data suggest that all fish species present are capable of surviving both summer and winter conditions when pond conditions could be most limiting. Food web structure among intensively sampled ponds was similar, with overlapping isotopic niche width for dominant taxa. However, basal resource diversity (BRD) varied among ponds, with those having higher macrophyte cover also showing greater BRD. Our findings suggest that pond-and-plug techniques can provide habitat for native fishes that are able to tolerate departures from the species thermal and dissolved oxygen optima. Future meadow treatments could benefit from short-term restoration techniques such as pond-and-plug to allow for longer-term processes to influence meadow condition over time. [ABSTRACT FROM AUTHOR]

Size dimorphic ungulates often display ecological differences attributed to body size. We predicted that male elk should select foraging sites containing more abundant forage than sites selected by smaller-bodied female and juvenile elk. To test this prediction, we estimated forage biomass at bite stations grazed by juvenile, adult female, and adult male Roosevelt Elk (Cervus elaphus roosevelti). Moreover, we examined the potential confounding influences of number of bites taken and group size on forage biomass at bite stations. We measured forage biomass associated with focal observations of 310 grazing elk (55 juveniles, 145 females, 110 males) in 2 meadow complexes in Redwood National and State Parks, California, 2008–2011. Analyzing a linear mixed effects model, our fixed effects showed that forage biomass at bite stations grazed by males tended to be greater than that of bite stations grazed by juveniles and females. When we considered the additional uncertainty from random effects, there was considerable overlap in 95% confidence intervals of estimated forage biomass at bite stations grazed by juvenile, female, and male elk. Therefore, the positive correlation between age-sex classes and forage biomass was weak. There also was no influence from number of bites taken at bite stations or group size on forage biomass at bite stations. When forage was limited, body size had a weak influence at bite stations grazed by juvenile, adult female, and adult male Roosevelt Elk. [ABSTRACT FROM AUTHOR]

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]

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.