Wildlife Monographs最新文献

Highly pathogenic avian influenza viruses (HPAIV) have had disastrous, worldwide effects on wild birds and domestic poultry since the emergence of the A/goose/Guangdong/1/1996 (Gs/GD/96) lineage. The currently circulating H5N1 clade 2.3.4.4b has an expanded set of susceptible hosts, including many migratory wild birds, and is associated with higher transmission rates, increased susceptibility among wild bird hosts, and a greater number of wildlife reservoirs. Certain wild bird life-history strategies and behaviors have been suggested to explain avian hosts’ susceptibility and exposure to HPAIV. These biological traits include gregariousness, such as colonial nesting and mixed flock foraging, predation or scavenging on wild birds, and association with aquatic habitats. Variation in host infection responses (e.g., infectability, shedding rates and duration, mortality rate, antibody development) informs the overall infection risk across avian species, yet the specific role of biological traits is often inconsistent and unclear across taxa. Moreover, the interactions and potential compounding effects among these biological traits remain largely unknown. To develop a more holistic understanding of cumulative risk across bird species, we integrate existing information on infection risk factors (i.e., susceptibility, immunological response, and behavioral traits) into a qualitative multivariate analysis. This approach enabled us to examine how infection risk factors relate to biological traits (e.g., phylogeny, physiology, behavior, species range) and to begin disentangling their complex interactions. We quantified and summarized these risk factors across host species and qualitatively ranked species by their viral responses along a proposed HPAIV response continuum, guided by expectations of traits and metrics associated with competence or vulnerability to HPAIV. In doing so, we aimed to better understand how viral responses and biological traits synergistically interact to influence cumulative risk across wild bird species. This work broadly expands on the previous avian influenza literature, which has focused on Anseriformes and Charadriiformes as primary viral reservoirs. We tie our findings to effective disease management responses with links to risk components, including descriptions of potential surveillance strategies applied to research and One Health goals, as well as a fuller understanding of how resources may be better deployed for rapid response when spillovers do inevitably occur. Additionally, we identified numerous areas where vital epidemiological information is lacking to best characterize the spread of these viruses. Ultimately, this improved understanding will help identify and inform disease management needs and decision making.

Wildfire has been a fundamental component of ecosystem dynamics for millennia. However, climate change, fire suppression, and land use practices have produced larger, more severe, and more frequent fires that threaten a range of wildlife species. Land managers in some fire-prone forest systems use fuels reduction treatments, including prescribed burning and mechanical thinning, to reduce vegetation density and the risk of large, high-severity fires. The strategy is to create forest landscapes that are more resilient to wildfire, which in turn will lessen the negative impact of uncharacteristically severe wildfire on wildlife. Yet there is uncertainty regarding the extent to which fire-adapted species are threatened by novel wildfire characteristics. The spotted owl (Strix occidentalis) has become a focal point for this controversy owing to its use of fire-suppressed forests that have been and will be vulnerable to changing fire regimes in the future. In this study, we attempted to address the question of how spotted owls respond to high-severity fire in California, USA, by leveraging 1) over 3 decades of detection–non-detection surveys in 1,514 historical spotted owl territories and 2) global positioning system (GPS) movement data from 171 individual spotted owls. Our study area included 7 national forests, 3 national parks, and extensive privately owned forests in California. Dynamic occupancy analysis indicated that spotted owl territories were more likely to become vacant and less likely to be colonized if they experienced recent and extensive high-severity fire. Consistent with the occupancy analysis, our movement analysis indicated that individual spotted owls avoided using severely burned forest. Although spotted owl territory persistence was higher in pyrodiverse territories (i.e., those with a mixture of low, moderate, and high severity burned areas), foraging owls showed mixed responses to local pyrodiversity, with some evidence that use of severely burned forest increased when pyrodiversity was high. We conclude that large and severe wildfires threaten the persistence of spotted owls in California. That said, forest restoration and fuels reduction treatments that reduce the risk of large and uncharacteristically severe fires while promoting multi-scale heterogeneity and pyrodiversity will likely benefit spotted owls and other species that occupy mixed conifer forests in California.