Barred Owls (Strix varia) recently expanded their range to include western North America and evidently are competing with federally threatened Northern Spotted Owls (S. occidentalis caurina). To help protect Spotted Owls, the US Fish and Wildlife Service (USFWS) is considering conducting a 3- to 10-y study in which as many as 2150 to 4650 Barred Owls would be killed and, possibly, carrying out long-term management of Barred Owls (Livezey 2010). To assist in these globally precedent-setting considerations, I present information concerning how frequently range expansions of North American birds and other factors may precipitate similar management issues in the near future. A total of 111 bird species (19.5%) recently expanded their breeding ranges into at least 1 new state or province. Fourteen species expanded their ranges into more states and provinces (range  =  13–46) than did Barred Owls (n =  12). Thirty-eight states or provinces have at least 10 more bird species than they did centuries ago. Human-caused changes to habitat (n =  84) or climate (n =  5) facilitated 98% of known or suggested range expansions, so it is likely range expansions will continue. If thousands of Barred Owls are killed because they expanded their range and are competing with a species of concern, it seems likely USFWS soon would need to consider whether to lethally intervene in conflicts between many other species of native birds due to the high frequency and large extent of range expansions, probability that range expansions will continue, increases in number of listed species, and further documentation of negative effects between species.

We describe the current distribution of native and non-native fishes in the Goose Lake basin, Oregon, with comparisons to prior unpublished surveys. We employed a generalized random tessellation stratified design to achieve a spatially-balanced sampling distribution across the drainage, including samples representative of both public and private lands. We collected all 9 native Goose Lake fishes, including 4 endemic fishes and the endangered Modoc Sucker. Two native fish species, the Modoc Sucker and the Pit Sculpin, were rarely encountered. The Modoc Sucker was limited to the upper Thomas Creek drainage; however, we documented a range expansion from that known at the time of listing in 1985. We collected the Pit Sculpin from only 2 sampling locations, indicating that the Oregon distribution of Pit Sculpins has contracted in the past 50 y. We also documented the apparent expansion of 2 non-native fishes, Fathead Minnow and Brown Bullhead, in the drainage. Within the Goose Lake fish assemblage, we describe 3 species groups that are correlated with land use and physical habitat parameters. The results of this study provide a baseline to assess trends in fish community structure over time and under different climatic conditions, measure the effects of restoration projects, and guide future restoration efforts.

As natural roosts of Big-ear Bats (Corynorhinus townsendii ssp.) are threatened or disappear, artificial roosts offering an acceptable microclimate may become an important component of the conservation strategy for this species. To determine how microclimate affects roosting behavior, I studied the responses of a maternity colony of Townsend's Big-eared Bats (C. t. townsendii) to varying temperature and humidity conditions in an attic roost. I constructed matrices of ambient temperature (T_a) and humidity from data logger recordings. I used a thermal imaging system to image the colony at 4 times on each of 4 days during the lactation period, recording size and location of each cluster or solitary individual. Clustering where it was warmest and apparent vasoconstriction of blood vessels in the ears were used to reduce heat loss at low T_a. Reduced clustering, movement to cooler locations, apparent vasodilation of blood vessels in the ears, and increased resting were used to increase heat dissipation at high T_a. The mechanisms used at both low T_a and high T_a probably also reduced metabolic rate and heat production. Humidity did not appear to affect cluster size and location. These results suggest that large, open-room structures offering a range of T_a and enough space for bats to spread apart would be important characteristics of artificial roosts for maternity colonies of C. t. townsendii.

The abundance of Band-tailed Pigeons (Patagioenas fasciata monilis) has declined substantially from historic numbers along the Pacific Coast. Identification of patterns and causative factors of this decline are hampered because habitat use data are limited, and temporal and spatial variability patterns associated with population indices are not known. Furthermore, counts are influenced not only by pigeon abundance but also by rate of visitation to mineral sites, which may not be consistent. To address these issues, we conducted mineral site counts during 2001 and 2002 at 20 locations from 4 regions in the Pacific Northwest, including central Oregon and western Washington, USA, and British Columbia, Canada. We developed inference models that consisted of environmental factors and spatial characteristics at multiple spatial scales. Based on information theory, we compared models within a final set that included variables measured at 3 spatial scales (0.03 ha, 3.14 ha, and 7850 ha). Pigeon counts increased from central Oregon through northern Oregon and decreased into British Columbia. After accounting for this spatial pattern, we found that pigeon counts increased 12% ± 2.7 with a 10% increase in the amount of deciduous forested area within 100 m from a mineral site. Also, distance from the mineral site of interest to the nearest known mineral site was positively related to pigeon counts. These findings provide direction for future research focusing on understanding the relationships between indices of relative abundance and complete counts (censuses) of pigeon populations by identifying habitat characteristics that might influence visitation rates. Furthermore, our results suggest that spatial arrangement of mineral sites influences Band-tailed Pigeon counts and the populations which those counts represent.

We investigated the diet and foraging behavior of a putative generalist predator, the Terrestrial Gartersnake, (Thamnophis elegans) along a stream in central Washington State, USA. Snakes were collected, with the sex, mass, and snout-vent length (SVL) of each recorded. Snakes were categorized by SVL into 3 groups (<300, 301–500, and >500 mm SVL). Snake SVL and mass ranged from 190–723 mm SVL (x ¯  =  425, s  =  140.41), and 3.6–150.5 (x ¯  =  43.3, s  =  38.5) respectively. Of the 263 snakes collected, 138 contained 141 prey items. The most abundant prey items were crayfish (n =  79, 56.2% of total), followed by cottid (n =  32, 22.6%) and cyprinid (n =  17, 12.0%) fish, and slugs (n =  13, 9.2%). The smallest group of snakes fed primarily on cyprinid fish and some slugs. These snakes foraged (sit and wait within runs), while perched on rocks or logs. The intermediate size class foraged along riffles, runs, and in pools, and had the broadest diet, feeding on cottid and cyprinid fish, crayfish, and slugs. The largest snakes were the most specialized, feeding primarily on crayfish while foraging in pools. Our data show that some individuals in this population of T. elegans undergo an ontogenetic shift in both diet (vertebrate to invertebrate) and foraging behavior (sit and wait to underwater foraging). This is also the 1st population of Thamnophis documented to feed primarily on crayfish.

One of the most widely used herbicides for commercial and home use is glyphosate, the active ingredient in Roundup® Regular. We examined toxicity of the herbicide Roundup® on 6 amphibian species: Ambystoma gracile, Ambystoma macrodactylum, Anaxyrus [Bufo] boreas, Pseudacris regilla, Rana cascadae, and Rana luteiventris. Larvae were exposed to 6 different Roundup® Regular treatments (0 (control), 0.1, 0.5, 1.0, 2.0, and 5.0 mg AI/L dilutions of glyphosate) and monitored for 16 d. Estimated acute lethal concentrations at 24 h (LC50) varied significantly among species (ANOVA, F_{(3, 56)}  =  3.54, p < 0.0202), with concentrations ranging from 0.43 mg AI/L of Roundup® for P. regilla to 2.66 mg AI/L for A. boreas. Bufonid and ambystomatid larvae were less sensitive than Ranid and Pseudacrid species tested, with no salamander larval mortality occurring at 24 h. Mean time-to-death varied from 1 d for P. regilla to 8.3 d for A. gracile, respectively (ANOVA, F_{(5, 971)}  =  108, p < 0.0001). For exposure times longer than 24 h, the A. boreas was not significantly different than the salamanders for time-to-death, based on Tukey-Kramer comparisons. Results suggest Roundup® Regular is highly toxic to the amphibians at levels below EPA standards for drinking water and at concentrations they may be exposed to during overspray. We recommend the use of less toxic glyphosate-based herbicides in aquatic systems, if applications are necessary, or made during times of year when amphibian larvae are not present.