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The Harney Basin is Oregon's largest internally draining basin and contains a unique native fish assemblage. The first and only comprehensive study of the origin and distribution of Harney Basin fishes occurred in 1971. Here, we update this study and identify potential threats to the basin's native fishes a half century later. Our assessment documents that all species of native fishes are still present, and with some exceptions distributed as originally reported. The distinctive fish assemblages in each of the 3 major subbasins within the Harney Basin (Silvies River, Silver Creek, and Donner und Blitzen River) support the hypothesis that terminal lakes in the Harney Basin (Malheur, Mud, and Harney Lakes) act as dispersal barriers, at least for native species. More than half of the fish species in the basin at present are introduced, primarily inhabiting low-elevation sites. We suggest that native non-salmonid species cohabiting these sites face the most immediate threats from climate change, water demands, and impacts from introduced fishes. Overall, our results show that native fish are still relatively widespread across the Harney Basin, but also face increasing threats despite the basin having experienced less development than many other areas in the Pacific Northwest. Improved understanding of the unique fishes of the Harney Basin, along with more detailed assessments of likely future trajectories of environmental risks are proactive measures that could improve conservation outcomes.
Four naturalized landbird species and 7 Galliform species are well established in Idaho. These species initially appeared in the state between 1870 to 2001 and usually became widespread within 1 or 2 decades. Combined, these 11 naturalized species account for 70.3% of all land birds counted on Idaho Christmas Bird Counts (CBC) from 1990–2018. Naturalized species made up 6.2% of land birds on Idaho Breeding Bird Surveys routes (BBS). Rock Pigeons (Columbia livia), European Starlings (Sturnus vulgaris), and House Sparrows (Passer domesticus) were the 3 most abundant land birds on 1990–2018 Idaho CBC and were common on Idaho BBS. Since 1st appearing in 2001, Eurasian Collared-Dove (Streptopelia decaocto) populations grew exponentially through the mid-2010s before declining, and were the 4th most abundant bird on Idaho CBC from 2014–2018. Northern Bobwhite (Colinus virginianus) were locally common for over a century but are now probably extirpated. Gambel's Quail (Callipepla gambelii) were introduced near the Salmon-Lemhi River confluence where a small population persists. California Quail (Callipepla californicus), Gray Partridge (Perdix perdix), Chukar (Alectoris chukar), Ring-necked Pheasant (Phasianus colchicus), and Wild Turkey (Meleagris gallopavo) ranged from the 12th to 40th most common birds on the 1990–2018 Idaho CBC and but were less common on Idaho BBS. Populations of California Quail, Gambel's Quail and Wild Turkey have been increasing, Chukar and Gray Partridge stable, and Ring-necked Pheasant decreasing. Idaho hunters annually harvest 10,000s to 100,000s of these 5 game birds.
Summer brood-rearing habitat is important for sustaining populations of Greater Sage-Grouse (Centrocercus urophasianus). Although Sage-Grouse in many populations move to more mesic sites during the late brood-rearing period, some populations do not select for these resources as strongly. We used generalized linear mixed models to evaluate the locations of 51 Sage-Grouse hens in the Crab Creek Management Unit in central Washington State. We compared their proximity to mesic patches with that of a set of random locations. We further compared the distance to mesic patches between brooding and non-brooding hens, wet and dry years, and early and late seasons. Sage-Grouse hens did not show any greater affinity to mesic patches than random, nor did brooding hens show greater affinity to mesic patches than non-brooding hens. Further, Sage-Grouse hens did not show any greater proximity to mesic patches in dry years compared to wet years, nor did they appear to move closer to mesic patches later in the summer. To evaluate differences in mesic and upland forage resources for Sage-Grouse, we measured percent cover and richness of forbs, along with overall horizontal cover, at 23 paired transects in mesic and upland sites. We found that whereas the cover of highly preferred forbs was higher in mesic sites, there was no difference between habitat types when moderately preferred forbs were also considered. Forb richness was higher in upland sites. We suggest that upland sites may have sufficient forb cover and richness for foraging translocated Sage-Grouse in the Crab Creek area during the brooding season.
Raptors around the world have experienced marked declines from a variety of reasons in recent decades. We continued an effort that began in the 1940s to monitor an entire raptor community in a protected landscape in northwest Wyoming. Our goals were to describe basic information on nesting raptor ecology such as nesting substrate use, nest re-use, nest switching, and nest persistence, and to track changes in the raptor community over time. We searched a 31.1-km2 area intensively for all nesting raptors and surveyed a 841.1-km2 study area primarily for Red-tailed Hawks (Buteo jamaicensis) and Common Ravens (Corvus corax), but recorded other nesting raptors and corvids when observed. In 2001–2002 and 2014–2015, we located and monitored 182 nesting attempts during intensive monitoring in the smaller study area. Between 1992 and 2015, we located and monitored an additional 984 nesting attempts in the larger study area. Nests were used by 14 raptor species and 2 corvid species. Nests built in trees accounted for 92.5% of all located nests. Most nests, 75.3%, were used only 1 y, although nest re-use varied from 1 to 13 y. When a nest was reused, it was most commonly used by the same species. From the 1940s through 2015, very little change occurred in the raptor community with the exception of a slight decrease in Red-tailed Hawks and a slight increase in Common Ravens. Our results inform a basic understanding of nesting raptor needs and support the idea that protected landscapes may be effective tools for conserving species like raptors.
While radio-tracking a migrating Silver-haired Bat (Lasionycteris noctivagans) in Kootenay National Park, British Columbia, we obtained information that allowed us to calculate the flight speed of a free-flying individual. We estimate that over the tracking period, the radio-tagged bat's mean flight speed was approximately 45 km h–1. This is considerably faster than previous estimates of Silver-haired Bats' flight speeds and may have implications for data collected as part of the North American Bat Monitoring Program.
In a previous general note we described lethal intraspecific behavior by a male Anna's Hummingbird (Calypte anna) during winter near the northern extent of the species' breeding range. This note reports another observation of agonistic behavior by a male of this species, under similar conditions, that resulted in “near death,” but which the victim apparently survived.
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