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Understanding population dynamics of migratory birds requires baseline knowledge of nonbreeding distributions, migratory routes, and population-specific migratory connectivity. The Canada Warbler (Cardellina canadensis) is a declining Ncarctic-Ncotropical migratory songbird, but limited information exists describing its population-specific migration ecology. We aimed to understand how individuals from a central Appalachian breeding population were spatially distributed during the stationary nonbreeding period, infer the strength and pattern of migratory connectivity, and understand migratory route patterns. We deployed 32 geolocator tags on adult male birds in 2020 and 10 tags retrieved in 2021 provided usable data. Stationary nonbreeding season locations suggest moderate population connectivity, with birds clustered on the Andean slopes on each side of the Magdalena Valley in northern Colombia. Post-breeding (boreal fall) migration was largely overland through Mexico and Central America, and pre-breeding (boreal spring) migration routes were significantly farther cast based on the westernmost longitude recorded during migration (mean difference = 232 km), consistent with a pattern of counterclockwise loop migration. The evidence of counterclockwise loop migration is a novel finding in Canada Warblers and suggests the shorter duration of pre-breeding migration may be due to a time-minimizing strategy involving trans-Gulf flights. Our data additionally provide the first insight into the migratory ecology of a population of Canada Warblers breeding near the southern extent of their range and serve as a foundation for full annual cycle demographic modeling. Received 10 June 2023. Accepted 30 December 2023. Key words: annual cycle, Colombian Andes, loop migration, migratory connectivity, West Virginia. Entender las dinamicas de poblacion de las aves migratorias requiere conocimiento de linea base de sus distribuciones no reproductivas, rutas de migracion y conectividad migratoria especifica de la poblacion. La reinita Cardellina canadensis es un ave canora migratoria Neartica-Neotropical, pero existe informacion limitada que describa la ecologia migratoria especifica de sus poblaciones. Nuestro objetivo era entender como los individuos de la poblacion reproductiva de los Appalachian centrales estaba distribuida espacialmente durante el periodo estacionario no reproductivo, inferir la fuerza y el patron de conectividad migratoria y entender los patrones de rutas migratorias. Colocamos 32 marcas de geolocalizacion en aves masculinas adultas en el 2020 y recuperamos 10 marcas en el 2021 con datos utilizables. Las localizaciones estacionarias de la estacion no reproductiva sugieren una moderada conectividad de poblaciones, con aves agrupadas en las pendientes de los Andes en cada lado del Valle de Magdalena en el norte de Colombia. La migracion post reproductiva (otono boreal) fue mayormente sobre el continente a traves de Mexico y Centroamerica y las rutas pre reproductivas (primavera boreal) fueron significativamente mas hacia el este basadas en la longitud mas al oeste registrada durante la migracion (diferencia promedio = 232 km), lo que es consistente con un patron de migracion circular en direccion contra reloj. La evidencia de la migracion circular a contra reloj es un descubrimiento nuevo para las reinitas Cardellina canadensis y sugiere que la duracion menor de migracion pre reproductiva puede deberse a una estrategia de minimizar el tiempo que involucran los vuelos trans-Golfo. Nuestros datos adicionales dan un primer acercamiento a la ecologia migratoria de una poblacion de reinitas Cardellina canadensis que se reproducen cerca de la parte mas sureno de su rango y sirve como base para modelar de un ciclo anual demografico completo. Palabras clave: ciclo anual, Andes colombianos, migracion circular, conectividad migratoria, West Virginia., Migratory connectivity describes the strength of population cohesion throughout the full annual cycle (Webster et al. 2002). Processes during one period of the annual cycle may be shaped by carryover [...]

Over the past few decades, cities have experienced increased floods affecting property and threatening human life as a result of a warming planet. There is still an incomplete understanding of the flood risk patterns in urban communities with different socioeconomic characteristics. In this study, we produced separate flood exposure and vulnerability indices based on relevant factors, then combined them as a risk index for Houston, Texas and Charleston, West Virginia. We applied statistical methods to extract the most significant social vulnerability factors in each study area. Finally, we mapped significant hot spots or clusters of high flood risk and compared results to socioeconomically disadvantaged populations. Based on the results, high-risk or 1%-annual-chance floodplains cover 23% of the Houston and 7% of Charleston study areas. Within these floodplains, 13% of the total developed land in Houston and 9% in Charleston are situated. In the event of a 1%-annual-chance flood, an estimated 5% of the total population in Houston and 6% in Charleston may require evacuation. Statistically significant flood risk clusters could only be identified in Houston. The implications from this work help to provide an analysis framework for larger urban areas while offering suggestions for its improvement in smaller populated areas. [ABSTRACT FROM AUTHOR]

Outdoor recreation is one of the fastest-growing economic sectors in the United States and is being used by communities to support economic development, social prosperity, and environmental protection. For communities that have whitewater rivers, whitewater recreation provides a powerful economic alternative to ailing extractive and manufacturing industries that have long dominated rural communities. In order to promulgate a whitewater recreation-based economy, stakeholders need information about their whitewater resources, including how often and when they can be paddled. The overall goal of this study, therefore, was to develop an analytical framework that quantifies boatable days, that is, the number of days that streamflow exceeds the minimum boatable flow levels needed to paddle downstream. Importantly, our framework uses publicly available streamflow and minimum boatable flow information that can be used to quantify boatable days for any whitewater run in the country, irrespective of watershed size or river flashiness. We applied the framework to three world-class whitewater rivers in the central Appalachian Mountains, USA, and found abundant and stable boating opportunities throughout the year. Our results underscore the potential for strategically developing whitewater recreation as a means of economic diversification and highlight how boatable days analysis can be used for quantifying whitewater resources. [ABSTRACT FROM AUTHOR]

Flood risk, encompassing hazard, exposure, and vulnerability is defined concerning potential losses. Machine learning techniques have gained traction among researchers to address the complexities of multi-variable flood risk assessment models and overcome issues associated with non-linear relationships. However, the focus has primarily been on flood hazard prediction rather than comprehensive risk assessment and damage estimations. Therefore, there is a need for experiments that combine risk elements using such methods. To address this need, this study utilized the Random Forest algorithm to analyze the correlations between the physical flood damage caused by Hurricane Harvey in 2017 in Houston, Texas and certain hazard, exposure, and vulnerability-related variables. The study identified poorly drained soils as the primary contributor to the losses, followed by population density and the ratio of developed lands with medium intensity. The study's findings also explored the reasons for the unexpectedly low importance of social vulnerability factors compared to the environmental justice concept. These findings and conclusions can provide insights to planners and stakeholders enhancing their understanding of the underlying causes contributing to flood risk. Future research can expand upon this study's methodology and findings by incorporating additional factors related to climate change. [ABSTRACT FROM AUTHOR]

Timber harvest is used to promote early-successional and mature forest songbird populations and diversity in forested landscapes, but we have an incomplete understanding of long-term bird responses to landscape-scale harvest intensity. Here, we used 17 years of historical bird survey data to address this knowledge gap by investigating how avian diversity, abundance, and population dynamics changed over time in two Central Appalachian forested landscapes with varying levels of timber harvest intensity. Our specific objectives were to examine the influence and effect of interactions between time and landscape-scale timber harvest intensity on breeding season songbird guild richness, focal species abundance, and focal species nest success. We found that guild richness and focal species abundance tended to be consistently higher in the actively harvested landscape, and trends in guild richness and species abundance over time were consistently positive in the actively harvested landscape and negative in the minimally harvested landscape. In particular, early-successional / edge-associated species and forest-gap species were found in higher numbers and exhibited positive temporal trends in the actively harvested landscape. However, a holistic assessment that included trends in reproductive success highlighted long-term declines in nest success for a forest-interior species of regional conservation concern within the actively harvested landscape but not the minimally harvested landscape. Thus, there are important trade-offs to consider when using landscape-scale forest management to promote songbird communities and populations in forested landscapes. While timber harvest operations can benefit particular songbird guilds and species, it is also valuable to maintain minimally harvested landscapes, and potentially manage for old-growth conditions, to support bird species that require extensive stands of mature forest. [Display omitted] • We tracked forest bird metrics in an actively vs. minimally harvested landscape. • Richness and abundance increased over time in the actively harvested landscape. • Richness and abundance decreased over time in the minimally harvested landscape. • Wood thrush nest success declined over time in the actively harvested landscape. • It is important to consider the trade-offs of landscape-scale forest management. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2006.01.007 Byline: Michael P. Strager (a), Randall S. Rosenberger (b) Keywords: Land conservation; Multicriteria analysis; Compromise programming; Geographic information systems Abstract: Landscape characteristics and parcel ownership information are often collected on different spatial scales leading to difficulties in implementing land use plans at the parcel level. This study provides a method for aggregating highly resolute landscape planning information to the parcel level. Our parcel prioritization model directly incorporates a Land Trust's conservation goals in the form of a compromise programming model. We then demonstrate the use of our approach for implementation decisions, including parcel selection under a budget constraint and the estimation of a total conservation budget necessary to meet specific conservation goals. We found that these cost constraints significantly alter the composition of the 'best' parcels for conservation and can also provide guidance for implementation. The model's results were integral to a local Land Trust's ability to further define and achieve their goals. Author Affiliation: (a) Division of Resource Management, West Virginia University, 2006 Agricultural Science Building, Morgantown, WV 26506-6108, USA (b) Department of Forest Resources, Oregon State University, 109 Peavy Hall, Corvallis, OR 97331-5703, USA Article History: Received 14 January 2005; Revised 17 December 2005; Accepted 4 January 2006