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Patterns of species' distribution and abundance are dynamic in response to changes in land cover, climate, interspecific relationships, and other factors. There are many examples of latitudinal range expansions, contractions, and shifts associated with warming climate. Global change effects are also manifested along gradients of longitude, and woody plant encroachment westward into the Great Plains might also be creating opportunities for species to expand into new areas. We used data from the North American Breeding Bird Survey (BBS) to examine the abundance of Red-bellied Woodpecker (Melanerpes carolinus) at a western edge of its distribution in Texas, Oklahoma, and Kansas. We compared BBS data from 1968-1992 to data from 1993-2018, fitting a series of generalized linear models to best explain variability in abundance. The best performing model included an interaction between time period and longitude, indicating both a change in abundance and in the distribution of abundance over time. Specifically, we found that Red-bellied Woodpecker increased in abundance near its western distributional limit over the past 5 decades, beginning at approximately -94 degrees longitude. Received 22 January 2023. Accepted 27 August 2023. Key words: distribution, expansion, Great Plains, longitude, North American Breeding Bird Survey., Los patrones de distribucion y abundancia de las especies son dinamicos en respuesta a los cambios en uso del suelo, el clima, las relaciones interespecificas y otros factores. Existen muchos [...]

Renewable energy production can kill individual birds, but little is known about how it affects avian populations. We assessed the vulnerability of populations for 23 priority bird species killed at wind and solar facilities in California, USA. Bayesian hierarchical models suggested that 48% of these species were vulnerable to population-level effects from added fatalities caused by renewables and other sources. Effects of renewables extended far beyond the location of energy production to impact bird populations in distant regions across continental migration networks. Populations of species associated with grasslands where turbines were located were most vulnerable to wind. Populations of nocturnal migrant species were most vulnerable to solar, despite not typically being associated with deserts where the solar facilities we evaluated were located. Our findings indicate that addressing declines of North American bird populations requires consideration of the effects of renewables and other anthropogenic threats on both nearby and distant populations of vulnerable species.

Nest site selection is crucial for survival and fecundity of birds. Predators find nests using visual, aural, thermal, and olfactory cues, yet few studies have evaluated olfactory concealment of nests. Rat snakes (Pantherophis spp.) are common nest predators that use ground-level olfactory cues to detect nest locations. In Arkansas, USA, we evaluated if cavity locations of the Redcockaded Woodpecker (Dryobates borealis, RCW), a species that experiences nest predation by rat snakes, were associated with airflow conditions known to provide olfactory concealment for other bird species. We used a 3-dimensional sonic anemometer to measure ground-level air velocity, turbulence, and turbulence intensity at cavity trees and unused trees, and at cavity and opposite orientations on trees. For all airflow variables, we found no differences between used and unused trees and orientations. Other factors such as landscape-scale vegetation cover, forest stand structure, and tree characteristics may be more important for providing visual concealment or optimal foraging conditions. However, it remains possible that such factors also convey olfactory concealment. For example, savannahlike forests preferred by RCWs may have greater air turbulence than closed forests. Further research on RCWs and other bird species to address additional aspects of olfactory concealment, and relationships between different dimensions of concealment (e.g., between visual and olfactory concealment), would give insight into how habitat management could provide multiple benefits to birds. Received 23 July 2021. Accepted 7 December 2021. Key words: airflow patterns, cavity orientation, cavity tree, habitat selection, olfactory cover. (Spanish)--La seleccion de sitios de anidacion es crucial para la sobrevivencia y fecundidad de las aves. Los depredadores encuentran nidos usando pistas visuales, aciisticas, termales y olfatorias, si bien pocos estudios han evaluado el escondite olfatorio de los nidos. Las serpientes Pantherophis spp. son depredadores de nidos comunes que usan pistas olfatorias a nivel del suelo para detectar el sitio de los nidos. En Arkansas, EUA, evaluamos si la localization de cavidades del carpintero Dryobates borealis (en adelante RCW), una especie que experimenta depredation de nidos por estas serpientes, esta asociada a las condiciones de circulation del aire conocidas como proveedoras de escondite olfatorio en otras especies de aves. Usamos un anemometro sonico tridimensional para medir la velocidad del aire a nivel del suelo. turbulencia e intensidades de turbulencia en arboles con cavidades y en arboles sin utilizar, ademas de cavidades y orientaciones opuestas en arboles. En ninguna de las variables de flujo de aire encontramos diferencias entre arboles utilizados. noutilizados y sus orientaciones. Otros factores como cobertura vegetal a escala de paisaje, estructura de la parcela de bosque y caracteristicas de los arboles podrian ser mas importantes para proveer escondite visual o condiciones optimas para el forrajeo. Sin embargo, sigue siendo posible que dichos factores tambien provean escondite olfatorio. Por ejemplo, los bosques similares a sabanas que son preferidos por RCW podrian tener mayor turbulencia del aire que los bosques cerrados. Mas investigaciones para detcrminar aspectos adicionales dc escondites olfatorios, y la relation entre diferentes dimensiones del escondite (e.g., entre escondite visual y olfatorio) en RCW y en otras aves, podrian darnos indicios sobre como el manejo de habitat podria proveer multiples beneficios a las aves. Palabras clave: arboles con cavidades, cobertura olfatoria, orientation de cavidades, patrones de flujo de aire, seleccion de habitat., Habitat selection is crucial for animal survival and fecundity. For birds, habitat selection is influenced by many factors, but predator avoidance is often a top priority, especially during nesting (Ricklefs [...]

Rickettsia parkeri, part of the spotted fever group Rickettsia (SFGR), affects humans throughout much of the southern United States (1). Although R. parkeri in an engorged nymph was reported once [...]

Wetland ecosystems are vital for maintaining global biodiversity, as they provide important stopover sites for many species of migrating wetland-associated birds. However, because weather determines their hydrologic cycles, wetlands are highly vulnerable to effects of climate change. Although changes in temperature and precipitation resulting from climate change are expected to reduce inundation of wetlands, few efforts have been made to quantify how these changes will influence the availability of stopover sites for migratory wetland birds. Additionally, few studies have evaluated how climate change will influence interannual variability or the frequency of extremes in wetland availability. For spring and fall bird migration in seven ecoregions in the south-central Great Plains of North America, we developed predictive models associating abundance of inundated wetlands with a suite of weather and land cover variables. We then used these models to generate predictions of wetland inundation at the end of the century (2069-2099) under future climate change scenarios. Climate models predicted the average number of inundated wetlands will likely decline during both spring and fall migration periods, with declines being greatest in the eastern ecoregions of the southern Great Plains. However, the magnitude of predicted declines varied considerably across climate models and ecoregions, with uncertainty among climate models being greatest in the High Plains ecoregion. Most ecoregions also were predicted to experience more-frequent extremely dry years (i.e., years with extremely low wetland abundances), but the projected change in interannual variability of wetland inundation was relatively small and varied across ecoregions and seasons. Because the south-central Great Plains represents an important link along the migratory routes of many wetland-dependent avian species, future declines in wetland inundation and more frequent periods of only a few wetlands being inundated will result in an uncertain future for migratory birds as they experience reduced availability of wetland stopover habitat across their migration pathways. [ABSTRACT FROM AUTHOR]

Wetlands provide many ecosystem services and functions, including critical stopover habitat for numerous migratory bird species. Yet, loss and degradation of wetlands due to land use and land cover changes have greatly reduced wetland extent worldwide, leading to declines of many migratory shorebirds globally. In the Western Hemisphere, wetlands of the North American Great Plains provide important stopover habitat for shorebirds; however, much remains to be learned about shorebird habitat use during stopovers in this region, including species-specific associations with landscape-scale wetland availability and characteristics of individual wetlands. To improve understanding of shorebird habitat use during migration, we conducted shorebird surveys at > 14 000 wetlands throughout Oklahoma, USA, from 2007 to 2009. For 16 shorebird species, we analyzed associations between observed abundance and wetland variables, including within-wetland characteristics and availability of wetlands at multiple spatial scales surrounding survey locations. We found that the scale at which observed abundance of shorebirds was associated with wetland extent varied among species; 10 species responded most strongly to wetland extent at the 500 m scale, but 5 species and 1 species responded most strongly at 1000 and 2000 m scales, respectively. Observed abundance for most species was generally associated with higher wetland density at broad scales, presence of extensive shallow water, more usable area, and limited vegetation within wetlands, yet there was considerable interspecific variation in the strength and in some cases direction of effects of these within-wetland characteristics. This interspecies variability highlights the importance of conserving a variety of wetland types with differing characteristics that support the entire shorebird community during migration. By informing optimal habitat requirements for shorebirds during a critical stage of their annual cycle, knowledge gained about species-specific habitat needs from studies like ours can assist with development of conservation and management strategies that contribute to halting and reversing global shorebird declines. [ABSTRACT FROM AUTHOR]

Predator-prey interactions influence behaviors and life-history evolution for both predator and prey species and also have implications for biodiversity conservation. A fundamental goal of ecology is to clarify mechanisms underlying predator- prey interactions and dynamics. To investigate the role of predator sensory mechanisms in predator-prey interactions, specifically in predator detection of prey, we experimentally evaluated importance of visual and olfactory cues for an apex predator, the coyote (Canis latrans Say, 1823). Unlike similar studies, we examined use of sensory cues in a field setting. We used trail cameras and four replicated treatments--visual only, olfactory only, visual and olfactory combined, and a control--to quantify coyote visitation rates in North American deciduous forests during fall 2016. Coyote visitation was greatest for olfactory-only and visual-only cues, followed by the combined olfactory-visual cue; all cues attracted more coyotes than the control (i.e., olfactory = visual > olfactory-visual > control). Our results suggest this apex predator uses both olfactory and visual cues while foraging for prey. These findings from a field study of free-roaming coyotes increase understanding of predator foraging behavior, predator- prey interactions, and sensory ecology. Our study also suggests future directions for field evaluations of the role of different sensory mechanisms in predator foraging and prey concealment behaviors. Key words: Canis latrans, coyote, foraging ecology, habitat selection, habitat use, olfactory concealment, predator-prey interactions, sensory cues, visual concealment. Les interactions prédateurs-proies influencent les comportements et l'évolution du cycle biologique tant pour les espèces de prédateurs que pour celles de proies et sont également importantes pour la conservation de la biodiversité. La détermination des mécanismes qui sous-tendent les interactions et la dynamique prédateurs-proies constitue un objectif fondamental de l'écologie. Pour examiner le rôle des mécanismes sensoriels des prédateurs dans les interactions prédateurs- proies, plus précisément dans la détection de proies par les prédateurs, nous avons évalué de manière expérimentale l'importance de signaux visuels et olfactifs pour un prédateur de niveau trophique supérieur, le coyote (Canis latrans Say, 1823). Contrairement à d'autres études semblables, nous avons examiné l'utilisation de signaux sensoriels sur le terrain. Nous avons utilisé des caméras de chasse et quatre traitements répliqués--visuel seulement, olfactif seulement, visuel et olfactif combinés et un témoin--pour quantifier la fréquence de visites de coyotes dans des forêts de feuillus d'Amérique du Nord à l'automne 2016. La fréquence des visites de coyotes était la plus grande pour les signaux seulement olfactif et seulement visuel, suivis par les signaux olfactif et visuel combinés; tous les signaux attiraient plus de coyotes que le témoin (c.-à-d., olfactif = visuel > olfactif- visuel > témoin). Nos résultats indiqueraient que ce prédateur de niveau trophique supérieur utilise des signaux olfactifs et visuels dans sa quête de proies. Ces constatations tirées de l'étude sur le terrain de coyotes en liberté accroissent la compréhension du comportement de quête de nourriture des prédateurs, des interactions prédateurs-proies et de l'écologie sensorielle. L'étude suggère également de futures directions pour l'évaluation sur le terrain du rôle de différents mécanismes sensoriels dans les comportements de quête de nourriture des prédateurs et de dissimulation des proies. [Traduit par la Rédaction] Mots-clés : Canis latrans, coyote, écologie de la quête de nourriture, sélection d'habitat, utilisation de l'habitat, dissimulation olfactive, interactions prédateurs-proies, signaux sensoriels, dissimulation visuelle., Introduction Predator-prey interactions are a key class of community interactions that influence ecosystem dynamics (Dulvy et al. 2004; Beauchamp et al. 2007; Ripple and Beschta 2012), drive behavioral and life-history [...]