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Wildfire and mountain pine beetle infestations are naturally occurring disturbances in western North American forests. Black-backed woodpeckers (Picoides arcticus) are emblematic of the role these disturbances play in creating wildlife habitat, since they are strongly associated with recently-killed forests. However, management practices aimed at reducing the economic impact of natural disturbances can result in habitat loss for this species. Although black-backed woodpeckers occupy habitats created by wildfire, prescribed fire, and mountain pine beetle infestations, the relative value of these habitats remains unknown. We studied habitat-specific adult and juvenile survival probabilities and reproductive rates between April 2008 and August 2012 in the Black Hills, South Dakota. We estimated habitat-specific adult and juvenile survival probability with Bayesian multi-state models and habitat-specific reproductive success with Bayesian nest survival models. We calculated asymptotic population growth rates from estimated demographic rates with matrix projection models. Adult and juvenile survival and nest success were highest in habitat created by summer wildfire, intermediate in MPB infestations, and lowest in habitat created by fall prescribed fire. Mean posterior distributions of population growth rates indicated growing populations in habitat created by summer wildfire and declining populations in fall prescribed fire and mountain pine beetle infestations. Our finding that population growth rates were positive only in habitat created by summer wildfire underscores the need to maintain early post-wildfire habitat across the landscape. The lower growth rates in fall prescribed fire and MPB infestations may be attributed to differences in predator communities and food resources relative to summer wildfire.

Declines in Greater Sage-Grouse (Centrocercus urophasianus, hereafter sage-grouse) populations could be attributed to low chick survival, which may be influenced by the availability of food and cover at sites used by females rearing broods. Habitat attributes important to broods may vary regionally; thus, it is necessary to understand factors affecting regional sage-grouse brood-rearing site selection, especially when estimating the impacts of development. We monitored brood-rearing female sage-grouse equipped with solar Argos Global Positioning System Platform Transmitter Terminals from 2011 to 2013 to assess microhabitat selection by broods in Carbon County, Wyoming. We measured vegetation and arthropod characteristics at diurnal sites used by broods (n = 42 in 2011, n = 31 in 2012, n = 32 in 2013) and at 3 paired-random sites associated with each used site (n = 315), located 50 m, 250 m, and 500 m from the used site. We fit conditional logistic models within an information-theoretic framework to identify vegetation and arthropod characteristics associated with microsite selection of brood-rearing sites. Sage-grouse selected brood-rearing sites with greater visual obstruction (0–45.7 cm in height), higher numbers of arthropods in the order Diptera, and lower numbers of arthropods in the order Coleoptera. There was an interaction effect between the number of arthropods in the order Hymenoptera and the canopy cover of broad-leaf forbs; the relative probability of selection increased with increasing number of Hymenoptera when there was low cover (<20%) of broad-leaf forbs, but decreased with increasing number of Hymenoptera when there was high broad-leaf forb cover (>20%). We also found a quadratic relationship between selection of brood-rearing sites and total vegetation canopy cover; the relative probability of selection increased until approximately 75% cover and then decreased with increasing cover. Sage-grouse rearing broods selected a diverse array of vegetation types, but greatest use occurred within mesic communities. Our results could be used to identify vegetation communities with high relative probabilities of use by sage-grouse rearing broods, which will help guide management decisions and provide reference conditions for future research that evaluates the effects of wind energy development on sage-grouse.

Movements among leks by breeding birds (i.e., interlek movements) could affect the population’s genetic flow, complicate use of lek counts as a population index, and indicate a change in breeding behavior following a disturbance. We used a Bayesian multi-state mark-recapture model to assess the daily probability of male greater sage-grouse (Centrocercus urophasianus) interlek movements and estimate factors influencing movements among leks. We fitted 145 males with solar Argos global positioning systems platform transmitter terminals over 4 years (2011–2014) in Carbon County, Wyoming, USA. The daily probability of a male sage-grouse moving among leks ranged 0.003 (95% CI = 0.000–0.010) in 2011 to 0.010 (95% CI = 0.001–0.021) in 2013, indicating high daily lek fidelity throughout the season, although there was a 5–42% chance annually a male would move at least once to another lek throughout the season (x̄ days analyzed/M = 55 ± 3.3 days [SE]). Interlek movement probabilities were strongly affected by day of year, peaking early in the lek season. Interlek movements were positively associated with elevation. Seasonal interlek movements occurred more frequently than previously reported, and can bias lek counts in early spring as males move from low to high elevation leks, which reinforces interlek movements as a critical component of lek ecology.

The Black Hills population of black-backed woodpeckers (Picoides arcticus) was petitioned, but deemed not warranted, to be listed as a threatened or endangered species under the Endangered Species Act and more information on their population size in the region is needed. Our objective was to map abundance and provide a population estimate of black-backed woodpeckers in the Black Hills and Bear Lodge Mountains of South Dakota and Wyoming, USA. We conducted 3,666 and 3,384 5-minute point count surveys from late-March to late-June in 2015 and 2016, respectively. We characterized vegetation around each point using geographic information system-derived landscape variables and fit 3-level hierarchical time-removal models in R package unmarked using gmultmix. The global abundance model received the most support and included year, latitude, and percent area of green trees, beetle-killed trees, dead trees, 1- to 2-year-old wildfire, 3-year-old wildfire, and 4- to 5-year-old wildfire. Points with high percent cover of beetle-killed trees had the greatest density of black-backed woodpeckers, followed by 1- to 2-year-old wildfires. After 4 years, areas burned by wildfire supported lower densities of black-backed woodpeckers than undisturbed forests. Mean density was 0.528 birds/km² in 2015 and 0.626 birds/km² in 2016. There were an estimated 2,920 and 3,439 black-backed woodpeckers in the Black Hills and Bear Lodge Mountains in 2015 and 2016, respectively. We suggest areas with high percent cover of beetle-killed trees may support high densities of black-backed woodpeckers and are important to sustaining populations when the availability of recent (<4 years old) wildfire is declining or scarce.

It is unlikely all male sage-grouse are detected during lek counts, which could complicate the use of lek counts as an index to population abundance. Understanding factors that influence detection probabilities will allow managers to more accurately estimate the number of males present on leks. We fitted 410 males with global positioning system and very high frequency transmitters, and uniquely identifiable leg- bands over 4 years in Carbon County, Wyoming. We counted male sage-grouse using commonly used lek- count protocols and evaluated variables associated with our ability to detect marked males using sightability surveys on 22 leks. We evaluated detection probabilities of male sage-grouse based on factors related to bird characteristics such as age or posture, lek and group size, lek characteristics such as vegetation cover or aspect, light conditions, weather, and observer. We then applied the detection probabilities to more accurately estimate male counts on leks. Detection probabilities were generally high (x̄ = 0.87) but varied among leks from 0.77 to 0.93. Male sage-grouse detection declined with increasing sagebrush height and bare ground and increased with more snow cover. Detection probabilities were also lower when observers counted from a higher elevation than the lek. Our sightability models predicted detection well and can be used to accurately estimate male abundance on leks from lek counts, which is especially useful where accurate abundance estimates are required or inference about population status is based on only 1 count. Further, it is important to consider lek attendance as a component of counts on leks because it affects availability of male sage-grouse for detection during lek counts. Detection can be maximized by conducting lek counts from 30 minutes before sunrise to 30 minutes after sunrise, although current protocols recommend lek counts can be performed up to 1 hour after sunrise. Detection can also be maximized by conducting lek counts ≥2 days after snowfall, which maximizes attendance and detection.

We studied elk (Cervus canadensis nelsoni) parturition sites at coarse (314-km2 and 7-km2) and fine (0.2-ha) scales in the Black Hills, South Dakota, 2011–2013, following a period of population decline and poor calf recruitment. Our objective was to test whether female elk selected parturition sites across spatial scales in association with forage, terrain ruggedness, road density, or hiding and security cover. At coarse scales in forests and grasslands, female elk selected sites in areas with greater proportions of vegetation communities that provided forage (56–74% of area) and more rugged topography (194—248 m) than found at random. At coarse scales in grasslands, elk selected sites in areas with lower road densities (≤1.24 km/plot). At the fine scale in forests and grasslands, female elk selected sites in areas with intermediate slope (19%), closer to water (355–610 m), and far from roads (541–791 m). Further, elk in forests and grasslands selected sites with intermediate security cover (50–88 m). We hypothesize elk selected for intermediate rugged terrain at larger scales for security from high road densities and human disturbance, but these areas may have placed elk in riskier environments for puma (Puma concolor) prédation. Forest management that maintains open-canopied vegetation communities in less rugged areas and prevents ponderosa pine (Pinus ponderosa) encroachment of meadows to provide forage may be beneficial for elk. Further, elk parturition sites occurred close to roads, particularly on public lands, and agencies should consider road-use restrictions and vegetation buffers beside roads in areas with less rugged terrain, which may provide favorable calving habitat.

Many North American birds associated with forest disturbances such as wildfire and mountain pine beetle (Dendroctonus ponderosae) outbreaks are declining in abundance. More information on relationships between avian abundance and forest structure and disturbance is needed to guide conservation and management. Our objective was to determine densities of American Three-toed Woodpecker (Picoides dorsalis), Black-backed Woodpecker (Picoides arcticus), Red-breasted Nuthatch (Sitta canadensis), Brown Creeper (Certhia americana), and White-winged Junco (Junco hyemalis aikeni) in relation to vegetation characteristics and disturbance at the point and landscape level in the Black Hills and Bear Lodge Mountains of South Dakota and Wyoming. We conducted 3 point counts from late March to late June 2015 and 2016 at more than 2,300 locations distributed across a gradient of forest structure and disturbance types. We estimated densities using 3-level hierarchical time-removal models that simultaneously estimated abundance, availability, and detection probability. Black-backed Woodpeckers were positively related to percent area in 1- to 3-year-old wildfires and Brown Creepers were positively associated with percent area in 4- to 5-year-old wildfires; however, Red-breasted Nuthatches were negatively related to percent area in 3- to 5-year-old wildfires. With the exception of American Three-toed Woodpeckers, species were positively related to percent cover of beetle-killed trees. Brown Creepers, White-winged Juncos, and Red-breasted Nuthatches had mixed responses to percent overstory canopy cover. White-winged Juncos also had a positive association with percent ground vegetation at the point and landscape level. Brown Creepers were strongly linked with spruce vegetation type. American Three-toed Woodpeckers, which are thought to occupy spruce forest in the Black Hills, did not show a strong relationship with any covariates. Maintaining some areas of natural disturbances along with heterogeneity of vegetation characteristics within stands and at the landscape scale will benefit the needs of a diverse bird community in the Black Hills.

Dramatic fluctuations in food resources are a key feature of many habitats, and many species have evolved a movement strategy to exploit food resources that are unpredictable in space and time. The availability of food resources may be a particularly strong determinant of habitat quality for irruptive bird species. We studied the apparent foraging success of Black-backed Woodpeckers (Picoides arcticus), an irruptive species that responds opportunistically to pulsed food resources in burned forests and mountain pine beetle (MPB) infestations. Prior investigations revealed that the highest population growth rates of Black-backed Woodpeckers occurred in habitat created by summer wildfire, with intermediate population growth rates in MPB infestations, and the lowest population growth rates in habitats created by prescribed fire in fall. We tested whether apparent foraging success was associated with known habitat quality in order to assess the potential for food availability to regulate population growth. We counted the number of successfully captured wood-boring beetle larvae and “small” prey on each tree that a Black-backed Woodpecker used for foraging and modeled these counts as a function of habitat, tree diameter, number of years postfire, and tree disturbance category. Total apparent foraging success (the sum of observed captures of wood-boring beetle larvae and small prey per tree) did not vary across habitats, but woodpeckers foraging in habitats created by summer wildfire were expected to capture 2.2 and 2.0 times more wood-boring beetles than woodpeckers foraging in habitats created by fall prescribed fire and MPB infestations, respectively. These results suggest that the availability of food resources may contribute to population regulation in this irruptive species. Furthermore, population growth in irruptive species may be highly sensitive to the availability of preferred food resources. Forests recently burned by summer wildfires provide relatively abundant food resources for Black-backed Woodpeckers and represent high-quality habitat for this species of conservation concern.

Greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) populations have declined across North America because of degradation of sagebrush (.Artemisia spp.) ecosystems; thus, management for sage-grouse habitat is a high priority. Expansion of some energy development has put additional pressures on sage-grouse populations and their habitats. However, little is known about the effects wind energy development may have on sage-grouse populations. Population dynamics of sage-grouse are partially related to nest success, which may be influenced by the quality of nesting habitat. Consequently, knowledge of vegetation and structural characteristics associated with selection and survival of sage-grouse nests would help inform management decisions to improve nest success. As part of a study quantifying greater sage-grouse demographics prior to construction of a wind energy facility, we monitored female sage-grouse equipped with 30-g solar Argos global positioning system platform transmitter terminals during the breeding season in Carbon County, Wyoming to assess selection and survival of nests at nest area (30-m radius), nest patch (5-m radius), and nest bowl scales. Sage-grouse selected nest sites with increased visual obstruction from 22.9–45.7 cm in height at all scales, less forb cover at the nest area, and more sagebrush cover at the nest patch. Survival of nests to 27 days (i.e., incubation period) was 43.3% (95% CI: 31.8–59.1%) in 2011 (n = 49), 33.2% (95% CI: 21.5–51.3%) in 2012 (» = 40), and 25.1% (95% CI: 15.0–42.0%) in 2013 (« = 39). Grass height had a positive association with survival of nests at the nest area and nest patch, canopy cover of bunchgrasses and sagebrush had an interactive effect on survival of nests at the nest patch, and visual obstmction from 0–22.9 cm in height had a positive relationship with survival of nests at the nest bowl. The standardized precipitation-evapotranspiration index (SPEI), an index of drought, from the previous growing season was also negatively correlated with survival of nests. Our results suggest management for nesting sage-grouse should focus on a heterogeneous compilation of tall bunchgrasses >15 cm and patches of sagebmsh cover >30%. Management for grasses >15 cm tall should be especially diligent during drought years, given SPEI was associated with nest survival the following year. Although there could be other factors important to selection or survival of nests that we did not evaluate, our results suggest scale-dependent management strategies at the microsite level may not be necessary. We encourage researchers and managers to use our baseline results in a before–after control-impact design with future, post-construction data to determine the potential effects of wind energy development on selection and survival of sage-grouse nests.

Nest success is an important parameter affecting population fluctuations of wild turkeys (Meleagris gallopavo). Factors influencing mammalian predation on turkey nests are complicated and not well understood. Therefore, we assessed nest hazard risk by testing competing hypotheses of Merriam's turkey (M. g. merriami) nest survival in a ponderosa pine (Pinus ponderosa) ecosystem during 2001–2003. We collected nesting information on 83 female Merriam's turkeys; annual nest success averaged 50% for adult females (range = 45–59%) and 83% for yearling females (range = 75–100%). Proportional hazard modeling indicated that precipitation increased the hazard of nest mortality. However, estimated hazard of nest predation was lowered when incubating females had greater shrub cover and visual obstruction around nests. Coyotes (Canis latrans) were the primary predator on turkey nests. We hypothesize that precipitation is the best predictor of nest survival for first nests because coyotes use olfaction effectively to find nesting females during wet periods. Temporally, as the nesting season progressed, precipitation declined and vegetation cover increased and coyotes may have more difficulty detecting nests under these conditions later in the nesting period. The interaction of concealment cover with precipitation indicated that nest hazard risk from daily precipitation was reduced with greater shrub cover. Management activities that promote greater shrub cover may partially offset the negative effects of greater precipitation events.