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A central theme for conservation is understanding how animals differentially use, and are affected by change in, the landscapes they inhabit. However, it has been challenging to develop conservation schemes for habitat‐specific behaviors.Here we use behavioral change point analysis to identify behavioral states of golden eagles (Aquila chrysaetos) in the Sonoran and Mojave Deserts of the southwestern United States, and we identify, for each behavioral state, conservation‐relevant habitat associations.We modeled behavior using 186,859 GPS points from 48 eagles and identified 2,851 distinct segments comprising four behavioral states. Altitude above ground level (AGL) best differentiated behavioral states, with two clusters of short‐distance movement behaviors characterized by low AGL (state 1 AGL = 14 m (median); state 2 AGL = 11 m) and two associated with longer‐distance movement behaviors and characterized by higher AGL (state 3 AGL = 108 m; state 4 AGL = 450 m).Behaviors such as perching and low‐altitude hunting were associated with short‐distance movements in updraft‐poor environments, at higher elevations, and over steeper and more north‐facing terrain. In contrast, medium‐distance movements such as hunting and transiting were over gentle and south‐facing slopes. Long‐distance transiting occurred over the desert habitats that generate the best updraft.This information can guide management of this species, and our approach provides a template for behavior‐specific habitat associations for other species of management concern., Despite the importance of linking habitat use to specific behaviors, this is almost never done, in part because of the many challenges in understanding where and when individual behaviors occur. Here, we use long‐term, short‐interval, and highly precise GPS data as input to recently developed models to interpret animal behavior from telemetry data to identify where and when behavioral states occur. Subsequently, we link these behavioral states to habitat, as a mechanism to identify the environmental correlates of each behavior, and to infer potential threats to these animals based on those behavior‐specific habitat associations.

Illegal killing of nongame wildlife is a global yet poorly documented problem. The prevalence and ecological consequences of illegal killing are often underestimated or completely unknown. We review the practice of legal recreational shooting and present data gathered from telemetry, surveys, and observations on its association with illegal killing of wildlife (birds and snakes) within conservation areas in Idaho, USA. In total, 33% of telemetered long‐billed curlews (Numenius americanus) and 59% of other bird carcasses found with known cause of death (or 32% of total) were illegally shot. Analysis of spatial distributions of illegal and legal shooting is consistent with birds being shot illegally in the course of otherwise legal recreational shooting, but snakes being intentionally sought out and targeted elsewhere, in locations where they congregate. Preliminary public surveys indicate that most recreational shooters find abhorrent the practice of illegal killing of wildlife. Viewed through this lens, our data may imply only a small fraction of recreational shooters is responsible for this activity. This study highlights a poorly known conservation problem that could have broad implications for some species and populations of wildlife.

Highway programmes typically focus on reducing vehicle collisions with large mammals because of economic or safety reasons, while overlooking the millions of birds that die annually from traffic. We studied wildlife–vehicle collisions along an interstate highway in southern Idaho, USA, with among the highest reported rates of American Barn Owl Tyto furcata road mortality. Carcass data from systematic and ad hoc surveys conducted in 2004–2006 and 2013–2015 were used to explore the extent to which spatial, road geometric and biotic factors explained Barn Owl–vehicle collisions. Barn Owls outnumbered all other identified vertebrate species of roadkill and represented > 25% of individuals and 73.6% of road‐killed birds. At a 1‐km highway segment scale, the number of dead Barn Owls decreased with increasing numbers of human structures, cumulative length of secondary roads near the highway and width of the highway median. The number of dead Barn Owls increased with higher commercial average annual daily traffic (CAADT), small mammal abundance index and grass rather than shrubs in the roadside verge. The small mammal abundance index was also greater in roadsides with grass vs. mixed shrubs, suggesting that Barn Owls may be attracted to grassy portions of the highway with more abundant small mammals for hunting prey. When assessed at a 3‐km highway segment scale, the number of dead Barn Owls again increased, with higher CAADT as well as with greater numbers of dairy farms. At a 5‐km scale, the number of dead Barn Owls increased with a greater percentage of cropland near the highway. Although human conversion of the environment from natural shrub‐steppe to irrigated agriculture in this region of Idaho has probably enhanced habitat for Barns Owls, it simultaneously has increased risk for owl–vehicle collisions where an interstate highway traverses the altered landscape. We review some approaches for highway mitigation and suggest that reducing wildlife–vehicle collisions involving Barn Owls may contribute to the persistence of this species.

Owing to habitat loss, changes in farming practices, urbanization, and high mortality through vehicle collisions, barn owls Tyto alba are a species of conservation concern in portions of their range. This species can be secretive and difficult to survey, particularly away from breeding sites, so factors related to barn owl occurrence often remain unknown. We conducted nighttime broadcast surveys for barn owls during the early- and post-breeding seasons and used an occupancy modeling framework to understand how factors related to landcover, landscape features, and human development related to occupancy in southern Idaho, USA. We also assessed the effectiveness of using broadcasts of conspecific vocalizations to improve owl detection. Barn owls were detected during 52 of 666 point counts and at 37 of 222 locations in the early-breeding season and 50 of 198 point counts and 31 of 66 locations in the post-breeding season. The probability of detecting barn owls was 0.32 ± 0.06 (SE) and 0.45 ± 0.07 (SE) during the early- and post-breeding seasons, respectively. Based on analysis within 1-km buffers surrounding point-count locations, occupancy in the early-breeding season increased with percentage of crop coverage and presence of trees and decreased with background noise. Post-breeding season occupancy increased with stream length and decreased with area of development and distance from the Snake River, a major geologic feature that likely provided roost sites in its canyon walls and riparian woodlands and a dispersal corridor for juveniles. Broadcast of barn owl vocalizations increased detection probability as much as nine times. Thus, incorporating call broadcast into future barn owl surveys should help investigators reduce false conclusions of absence. Ultimately, understanding factors influencing occupancy of barn owls will facilitate effective conservation, especially in light of population pressures related to factors such as roadway mortality and loss of nesting sites with increased urbanization.

We examined the temporal, spatial, and demographic factors that influenced roadway mortality of barn owls (Tyto alba) along a 248-km stretch of Interstate 84 in southern Idaho using systematic road surveys. Counts of dead animals from surveys can be underestimated because of sampling biases; therefore, we also conducted experiments to assess the effects of search and removal bias on the estimates of roadway mortality of owls. We conducted surveys every 2 weeks over a 2-year period and detected 812 dead barn owls (unadjusted mortality rate of 1.64 owls/km/yr). After adjusting this estimate for search and removal bias, we documented mortality rates of up to 5.99 owls/km/year. Owl mortality was not random in relation to sex, age class, or location along the highway. Females and juveniles, which represent individuals more likely to disperse long distances, were killed more frequently than males and adults. During the nonbreeding season, owls were killed more often near agricultural lands than in shrub-steppe, but this pattern was not apparent during the breeding season. Owls were also killed more often on portions of the roadway closer to the Snake River canyon, perhaps because of the availability of nest and roost sites. Mortality rates differed markedly between the 2 years of study, which could have been related to variability in weather and its subsequent effect on owl productivity. Our data suggest that barn owls in this region may not persist under this level of mortality without significant immigration or management. Thus, roadway management to reduce or prevent owl use of roadways, reduce rodent populations near major roads, alert motorists to the presence of owls, or otherwise reduce the chances that vehicles and owls collide would improve barn owl survival and population persistence. © 2012 The Wildlife Society.

Western burrowing owls (Athene cunicularia hypugaea) are endangered in Canada and several western U.S. states. Population declines have been linked with control measures aimed at burrowing mammals and loss of nesting habitat. The owls frequently associate with irrigated agriculture throughout portions of their western U.S. range. To determine potential factors driving the association of burrowing owls with agriculture, we examined availability of suitable nest burrows (burrow availability hypothesis), abundance of potential prey (prey availability hypothesis), and predation of nest burrows (predation hypothesis) for owls nesting in the Snake River Birds of Prey National Conservation Area in southwestern Idaho during 2001–2002. Nest burrow availability did not differ between agricultural and nonagricultural habitats, and occupancy rates of owls in artificial burrows were greater near agriculture. More rodent prey species were live-trapped in agricultural habitat compared with nonagricultural habit...

We performed a series of population and pedigree analyses to examine the viability of a small Red-cockaded Woodpecker (Picoides borealis) population located at the Savannah River Site, in Barnwell and Aiken counties of South Carolina. The population’s existence and future survival are precarious. As few as four individuals, including just one breeding pair, comprised this population in 1985. Now, primarily because of experimental transformation of birds from other areas, the population has increased to 25. As of 1990, genealogy pedigree analysis showed that the respective contribution of 14 founders to the extant population has not been equal. Founder gender equivalents are low (5.4) but could reach 9.2 if poorly-represented founders were to produce offspring. The fraction of founder gene diversity retained in the current population is 0.91. Successful recovery strategies would ensure 95% probability of population survival while maintaining 90% heterozygosity for 200 years. Viability analyses indicated that, depending on relative effects of inbreeding depression and stochastic environmental events, the Savannah River Site population has a 68–100% chance of extinction during this period. Annual translocation into the population of at least three females and two males for a 10-year period will achieve a 96% probability of survival for 200 years. Even with translocation of numerous males and females per year (up to 50 of each), the 90% heterozygosity goal may not be achieved. We discuss recommendations for choosing individuals for translocation logistical constraints on achieving recovery objectives, and limitations of our modeling approach. Realizamos una serie de analisis de poblacion y anallisis genealogicos para examinar la viabilidad de una pequena poblacion del pajaro carpintero cabeza roja (Picoides borealis) localizada en Savannah River Site, en los condados de Barnwell y Aiken de Carolina del Sur. La existencia de la poblacion y su futura superviviencia son precarias. En 1985, esta poblacion consistia solo de cuatro individuos, incluyendo una pareja de adultos. En la actualidad, y debido principalmente al traslado experimental de aves de otras areas, la poblacion a aumentado a 25. En 1990, un analisis “gene drop pedigree” demostro que la contribucion respectiva de los 14 individuos fundadores a la poblacion existente no ha sido equitativa. Los equivalentes de los genomas fundadores son bajos (5.4) pero podrian llegara a 9.2 si los fundadores pobremente representados produjesen descendencia La fraccion de la diversidad genetica de los individuos fundadores mantenida en la poblacion actual es de 0.91. Estrategias exitosas de recuperacion podrian asegurar una probabilidad de supervivencia poblacional del 95%, manteniendo al mismo tiempo un 90% de la heterocigosidad, por 200 anos. Los analisis de viabilidad indicaron que, dependiendo de los efectos relativos de la endocria y eventos ambientales estocasticos, la poblacion de Savannah River Site tiene, durante este periodo, una probabilidad de extincion del 68–100%, aproximadamente. El traslado anual de por lo menos tres hembras y dos machos por un periodo de 10 anos permitiria alcanzar una probabilidad de supervivencia de un 96% durante 200 anos. Aun con el traslado de numerosos machos y hembras por ano (hasta 50 de cada uno), no se podria llegar a alcanzar la meta de 90% de heterocigosidad. Discutimos recomendaciones para la eleccion de los individuos a ser trasladados, limitaciones logisticas para alcanzar los objetivos y limitaciones de nuestro metodo de modelado.