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Financial tools can present a solution to conservation conflicts. However, their effectiveness may be limited unless they address the underlying drivers of conflict. The restoration of controversial megafauna can be tied to a clash of urban and rural values and rejection by rural landowners of government control over their actions. Here, we consider a latent financial opportunity presented by general public support for large predator restoration to maintain a wolf-livestock coexistence program in Washington state, USA. We measured respondents' (N = 420) willingness-to-pay for gray wolf (Canis lupus) conservation and their preferences for program funding mechanisms, including voluntary contributions, mandatory taxes, and a ‘predator-friendly’ ranching certification scheme. Respondents were supportive of a publicly funded program, which represented around USD246 million in estimated economic value. This benefit is more than 150 times the cost of the current government-run program. There were mixed preferences for funding mechanisms, so we recommend adopting multiple approaches. A new funding source would allow the program to be rancher-led, shifting agency from government to rural communities, as well as providing outreach opportunities for ranchers to the urban public. As such, our proposal addresses two of the major socio-political conflicts underlying the wolf debate in North America while also generating funding to protect the ranching industry.

A thorough understanding of the effects of spatially and temporally variable demographic drivers of population processes is necessary to accurately evaluate potential source-sink dynamics, estimate long-term population viability, and devise effective management practices. The black-capped vireo (Vireo atricapilla) is an endangered songbird that suffers from high rates of parasitism by the brown-headed cowbird (Molothrus ater). The largest breeding population of vireos is located on the Fort Hood Military Installation in central Texas. This large reserve is well studied but its role in vireo metapopulation dynamics is largely unknown. Furthermore, the evolving cowbird control regime across Fort Hood and nearby isolated populations could impact the local source-sink dynamics. From 2011 through 2014, we monitored breeding vireos at eleven sites across central Texas that varied in cowbird control level. From observations of fecundity and survival, we calculated stochastic and deterministic population growth rates and assessed populations as sources or sinks. We also calculated quasi-extinction probabilities and the sensitivity and elasticity of population growth to demographic parameters. Sites with at least some cowbird control had greater nest success than sites with no cowbird control. We identified four source populations, three of which were on the large Fort Hood reserve and had comprehensive cowbird control across all study years. Although not all sites with cowbird control were sources on average, population dynamics were variable between years and the implementation of cowbird management was generally associated with the growth of local populations. Importantly, source and sink populations were not static, revealing a complex and temporally dynamic system driven largely by variations in adult survival and evolving cowbird control regimes.

Human conversion of land cover alters biotic communities and sets the stage for ongoing change as species interact within new environments. We studied the response of a native forest specialist, the Pacific wren ( Troglodytes pacificus ), to immediate and ongoing environmental changes facilitated by urbanization. We found evidence of a synergistic effect of native land cover loss followed by increased aggressive interactions with a native generalist, the Bewick’s wren ( Thryomanes bewickii ), resulting in the decline of Pacific wrens in urbanizing environments. Pacific wren relative abundance decreased dramatically during and after development, while Bewick’s wrens increased and persisted at greater abundance post-relative to pre-development. Breeding territories of the two species overlapped minimally, suggesting spatial segregation either by differential resource use or territorial aggression. A comparison of territory characteristics revealed the species generally used different resources, although territory composition was increasingly similar at urbanizing sites where the species co-occurred. Territorial playback experiments confirmed that the two species interact aggressively. Analyses of body size, body condition and reproductive success did not suggest Bewick’s wrens negatively impact fitness of Pacific wrens at sites where they co-occurred. In established subdivisions (>10 years old) Bewick’s wrens appear to limit the abundance of Pacific wrens, however this was not yet the case at sites we studied immediately after development. Although the results of this study are not conclusive, our findings are consistent with the hypothesis that new environmental gradients and communities created by urbanization increase competitive interactions among native species.

A thorough understanding of a population’s ecology requires knowledge of the relationship between habitat use, resource use and demographic parameters. We undertook an empirical investigation of habitat use, resource use and demography in a population of common ravens (Corvus corax), a species widely distributed throughout the Northern Hemisphere. The abundance of ravens is increasing in many parts of western North America, which represents a conservation concern since predation by ravens is thought to contribute to the decline of several sensitive species. We defined resources as the suite of physical and biological components in the environment that led to occupancy of a particular place by ravens. The home ranges of breeding and nonbreeding ravens contained similar proportions of resources, but breeding ravens used more edges, roads, forest, clearcuts, and towns than nonbreeders. We detected no differences in survival between the sexes, but breeding ravens survived at higher rates than nonbreeders, due to exclusion by breeding ravens from those resources positively associated with survival. Raven use of mature forests and anthropogenic land use types was positively associated with survival. Breeding raven use of clearcuts and patchy areas contributed to increased reproduction, but the use of clearcuts along with the use of roads was negatively associated with survival due to illegal shooting. Greater insight into the demography of synanthropic species such as the common raven will enable managers to make informed decisions for protecting biodiversity. This study is the first to consider the demographic consequences of habitat use and resource use for both nonbreeding and breeding common ravens.

Human development often favors species adapted to human conditions with subsequent negative effects on sensitive species. This is occurring throughout the urbanizing world as increases by generalist omnivores, like some crows and ravens (corvids) threaten other birds with increased rates of nest predation. The process of corvid responses and their actual effects on other species is only vaguely understood, so we quantified the population response of radio-tagged American crows (Corvus brachyrhynchos), common ravens (Corvus corax), and Steller’s jays (Cyanocitta stelleri) to human settlements and campgrounds and examined their influence as nest predators on simulated marbled murrelet (Brachyramphus marmoratus) nests on Washington’s Olympic Peninsula from 1995 to 2000. The behavior and demography of crows, ravens, and jays was correlated to varying degrees with proximity to human development. Crows and ravens had smaller home ranges and higher reproduction near human settlements and recreation. Annual survival of crows was positively associated with proximity to human development. Home range and reproduction of Steller’s jays was independent of proximity to human settlements and campgrounds. Local density of crows increased because home ranges of neighboring breeding pairs overlapped extensively (6× more than ravens and 3× more than Steller’s jays) and breeders far from anthropogenic foods traveled 10s of kilometers to access them. Corvids accounted for 32.5% of the predation events (n = 837) we documented on artificial murrelet nests. Small corvids (jays) were common nest predators across our study area but their contribution as predators did not vary with proximity to settlements and campgrounds. In contrast, large corvids (crows and ravens) were rare nest predators across our study area but their contribution varied greatly with proximity to settlements and campgrounds. Managers seeking to reduce the risk of nest predation need to consider the varied impacts and variable behavioral and population responses of potential nest predators. In our situation, removing large corvids may do little to reduce overall rates of nest predation because of the diverse predator assemblage, but reducing anthropogenic food in the landscape may be effective.