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167 result(s) for "conectividad"
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Meta-analysis of human connection to nature and proenvironmental behavior
Understanding what drives environmentally protective or destructive behavior is important to the design and implementation of effective public policies to encourage people’s engagement in proenvironmental behavior (PEB). Research shows that a connection to nature is associated with greater engagement in PEB. However, the variety of instruments and methods used in these studies poses a major barrier to integrating research findings. We conducted a meta-analysis of the relationship between connection to nature and PEB. We identified studies through a systematic review of the literature and used Comprehensive Meta-Analysis software to analyze the results from 37 samples (n = 13,237) and to test for moderators. A random-effects model demonstrated a positive and significant association between connection to nature and PEB (r = 0.42, 95% CI 0.36, 0.47, p < 0.001). People who are more connected to nature reported greater engagement in PEB. Standard tests indicated little effect of publication bias in the sample. There was significant heterogeneity among the samples. Univariate categorical analyses showed that the scales used to measure connection to nature and PEB were significant moderators and explained the majority of the between-study variance. The geographic location of a study, age of participants, and the percentage of females in a study were not significant moderators. We found that a deeper connection to nature may partially explain why some people behave more proenvironmentally than others and that the relationship is ubiquitous. Facilitating a stronger connection to nature may result in greater engagement in PEB and conservation, although more longitudinal studies with randomized experiments are required to demonstrate causation. El entendimiento de los conductores del comportamiento de protección o destrucción ambiental es importante para el diseño e implementación de políticas públicas que fomenten la participación de las personas dentro del comportamiento a favor del ambiente (PEB, en inglés). Las investigaciones muestran que la conexión con la naturaleza está asociada con una mayor participación en el PEB. Sin embargo, la variedad de instrumentos y métodos que utilizados en estos estudios presentan una barrera importante para la integración de los resultados de las investigaciones. Realizamos un metaanálisis de la relación entre la conexión con la naturaleza y el PEB. Identificamos estudios por medio de una revisión sistemática de la literatura y utilizamos software de Metaanálisis Completo para analizar los resultados de 37 muestras (n = 13,237) y para examinar a los moderadores. Un modelo de efectos azarosos demostró una asociación positiva y significativa entre la conexión con la naturaleza y el PEB (r = 0.42, 95% CI 0.36, 0.47, p < 0.001). Las personas que están más conectadas con la naturaleza reportaron una mayor participación en el PEB. Las pruebas estándares indicaron un efecto menor del sesgo de publicación en la muestra. Hubo una heterogeneidad significativa entre las muestras. Los análisis univariados categóricos mostraron que las escalas usadas para medir la conexión con la naturaleza y el PEB fueron moderadores significativos y explicaron la mayoría de la varianza entre estudios. La ubicación geográfica de un estudio, la edad de los participantes, y el porcentaje de mujeres en un estudio no fueron moderadores significativos. Encontramos que una conexión más profunda con la naturaleza puede explicar parcialmente por qué algunas personas se comportan más a favor del ambiente que otras y que dicha relación es ubicua. La facilitación de una conexión más fuerte con la naturaleza puede resultar en una mayor participación en el PEB y en la conservación, aunque se requieren estudios más longitudinales con experimentos aleatorios para demostrar la causalidad 理解保护环境和破坏环境行为背后的驱动力,对于设计和实施有效的公共政策以鼓励人们参与环保行动 至关重要 。 已有研究表明,与自然的联系和环保行动参与度之间存在相关性 。 然而,这些研究使用了各种各样 的工具和方法,导致这些研究結果难以整合 。 因此,我们对人与自然的联系和环保行为之间的关系进行了荟萃 分析 。 我们通过系统文献综述筛选出相关研究,并用综合荟萃分析软件分析了 37 个样本 (n = 13,237) 的研究结 果以检验干涉变量 。 随机效应模型显示, 亲近自然与环保行为之间有显著的正相关关系 (r = 0.42, 95% CI 0.36, 0.47, p < 0.001) 。 更亲近自然的人自我报告的环保行为参与度也更高 。 标准检测分析表明,样本中的研究发表 偏差的影响很小,而各样本间存在显著的异质性 。 单变量分类分析结果显示,用于测定人与自然的联系和环保 行为的尺度是重要的干涉变量,解释了大部分的研究间差异 。 而研究地点 、 参与者年龄和性別都不是显著的干 涉变量 。 我们还发现,与自然更深层次的联系可能部分解释了为什么有些人更环保,而且其间的相关性普遍存 在 。 促进人与自然更紧密的联系或能推动人们更多地参与环保和保护行动,尽管仍需要更多包含随机实验的纵 向研究来证明因果关系 。
Reserve design to optimize functional connectivity and animal density
Ecological distance-based spatial capture–recapture models (SCR) are a promising approach for simultaneously estimating animal density and connectivity, both of which affect spatial population processes and ultimately species persistence. We explored how SCR models can be integrated into reserve-design frameworks that explicitly acknowledge both the spatial distribution of individuals and their space use resulting from landscape structure. We formulated the design of wildlife reserves as a budget-constrained optimization problem and conducted a simulation to explore 3 different SCR-informed optimization objectives that prioritized different conservation goals by maximizing the number of protected individuals, reserve connectivity, and density-weighted connectivity. We also studied the effect on our 3 objectives of enforcing that the space-use requirements of individuals be met by the reserve for individuals to be considered conserved (referred to as home-range constraints). Maximizing local population density resulted in fragmented reserves that would likely not aid long-term population persistence, and maximizing the connectivity objective yielded reserves that protected the fewest individuals. However, maximizing density-weighted connectivity or preemptively imposing home-range constraints on reserve design yielded reserves of largely spatially compact sets of parcels covering high-density areas in the landscape with high functional connectivity between them. Our results quantify the extent to which reserve design is constrained by individual home-range requirements and highlight that accounting for individual space use in the objective and constraints can help in the design of reserves that balance abundance and connectivity in a biologically relevant manner. Los modelos de captura-recaptura espacial (CRE) basados en distancias ecológicas son un método prometedor para estimar la densidad animal y la conectividad, las cuales afectan los procesos poblacionales espaciales y, en última instancia, la persistencia de las especies. Exploramos cómo se puede integrar a los modelos CRE en los marcos de diseño de reserva que explícitamente reconocen tanto la distribución espacial de los individuos como su uso del espacio resultante de la estructura del paisaje. Formulamos el diseño de reservas de vida silvestre como un problema de optimización de presupuesto limitado y realizamos una simulación para explorar 3 diferentes objetivos de optimización informados por CRE que priorizaron diferentes metas de conservación mediante la maximización del número de individuos protegidos; la conectividad de la reserva y la conectividad ponderada por la densidad. También estudiamos el efecto sobre nuestros objetivos de hacer que los requerimientos individuales de uso de espacio fuesen satisfechos por la reserva de manera que se pudiese considerar que los individuos estaban protegidos (referidos como restricciones de rango de hogar). La maximización de la densidad de la población local resultó en reservas fragmentadas que probablemente no contribuyan a la persistencia de la población a largo plazo, mientras que la maximización de la conectividad produjo reservas que protegían al menor número de individuos. Sin embargo, la maximización de la conectividad ponderada por la densidad o la imposición preventiva de restricciones de rango de hogar en el diseño de reservas produjo reservas compuestas por conjuntos de parcelas mayormente compactas espacialmente que cubrían áreas de densidad alta en el paisaje con alta conectividad funcional entre ellas. Nuestros resultados cuantifican la extensiónalacualeldiseño de reservas esta limitado por los requerimientos de rango de hogar individuales y resaltan que la consideración del uso de espacio individual en el objetivo y limitaciones puede ayudar al diseño de reservas que equilibren la abundancia y la conectividad de manera biológicamente relevante. 基于生态距离的空间捕获-重捕模型(spatial capture-recapture model, SCR) 有望同时估计动物密度和连 接度,这两者通过影响种群空间过程,最终影响着物种续存。我们探究了如何将 SCR 模型整合到保护区设计框 架中,以兼顾个体的空间分布和对景观结构的空间利用。我们认为野生动物保护区设计可以看作是受预算限制 的最优化问题,并且模拟了三种基于 SCR 信息实现保护目标最优化的情况,即优先考虑保护个体数目最大化、 保护区连接度最优化以及密度加权的连接度最优化。我们还分析了在保护区满足个体:空间利用需求的前提下这 三个目标受到的影响,这个条件是为了确保个体凌到有效保护(即家域约束)。实现局部种群密度最大化会导致 保护区破碎化,这可能不利于种群的长期续存;而考虑连接度最优化则会导致保护区覆盖的个体数最少。然而, 考虑密度加权的连接度最优化,或在保护区设计中优先加人家域约束,则保护区会含有大量空间上紧密的斑块 以覆盖景观中种群密度高的地区,斑块之间功能连接度也较高。本研究结果量化分析了个体的家域需求的限制 对保护区设计的影响程度,并强调了在保护区设计的目标和限制中考虑个体:空间利用将有助于设计出生物学意 义上平衡丰度和连接度的保护区。
Connecting today's climates to future climate analogs to facilitate movement of species under climate change
Increasing connectivity is an important strategy for facilitating species range shifts and maintaining biodiversity in the face of climate change. To date, however, few researchers have included future climate projections in efforts to prioritize areas for increasing connectivity. We identified key areas likely to facilitate climate-induced species' movement across western North America. Using historical climate data sets and future climate projections, we mapped potential species' movement routes that link current climate conditions to analogous climate conditions in the future (i.e., future climate analogs) with a novel moving-window analysis based on electrical circuit theory. In addition to tracing shifting climates, the approach accounted for landscape permeability and empirically derived species' dispersal capabilities. We compared connectivity maps generated with our climate-hange-informed approach with maps of connectivity based solely on the degree of human modification of the landscape. Including future climate projections in connectivity models substantially shifted and constrained priority areas for movement to a smaller proportion of the landscape than when climate projections were not considered. Potential movement, measured as current flow, decreased in all ecoregions when climate projections were included, particularly when dispersal was limited, which made climate analogs inaccessible. Many areas emerged as important for connectivity only when climate change was modeled in 2 time steps rather than in a single time step. Our results illustrate that movement routes needed to track changing climatic conditions may differ from those that connect present-day landscapes. Incorporating future climate projections into connectivity modeling is an important step toward facilitating successful species movement and population persistence in a changing climate. Incrementar la conectividad es una estrategia importante para facilitarle a las especies cambios en su extensión y mantener a la biodiversidad de frente al cambio climático. Sin embargo, a la fecha pocos investigadores ban incluido las proyecciones del futuro climático en los esfuerzos priorizar áreas para incrementar la conectividad. Identificamos áreas clave con probabilidad de facilitar el movimiento de las especies inducido por el clima en América del Norte. Por medio de un análisis novedoso de ventana en movimiento basado en la teoría de los circuitos eléctricos, mapeamos las rutas potenciales de movimiento de las especies que enlazan las condiciones climáticas actuates con condiciones climáticas análogas en el futuro (es decir, futuros climas análogos) utilizando conjuntos de datos históricos del clima y las proyecciones del futuro climático. Además de rastrear los climas cambiantes, la estrategia tomó en cuenta la permeabilidad del paisaje y derivó empíricamente las capacidades de dispersión de las especies. Comparamos los mapas de conectividad generados con nuestra estrategia informada por el cambio climático con los mapas de conectividad basados solamente en el grado de modificación humana del paisaje. La inclusión de las proyecciones del futuro climático dentro de los modelos de conectividad modificó y restringió sustancialmente las áreas prioritarias de movimiento a una porción mas pequeña del paisaje que cuando no se consideraron las proyecciones climàticas. El movimiento potential, medido como el flujo de corriente, disminuyó en todas las ecoregiones cuando se incluyeron las proyecciones climáticas, particularmente cuando la dispersión estuvo limitada, lo que hizo que los análogos climáticos fueran inaccesibles. Muchas áreas emergieron como importantes para la conectividad sólo cuando el cambio climático fue modelado en pasos de dos tiempos, en lugar de un paso de un sólo tiempo. Nuestros resultados ilustran que las rutas de movimiento necesarias para rastrear las condiciones climáticas cambiantes pueden diferir de aquellas que conectan a los paisajes hoy en día. La incorporatión de las proyecciones del futuro climático dentro del modelado de conectividad es un paso importante hacia la facilitatión del movimiento exitoso para las especies y la persistencia de las poblaciones en un clima cambiante.
A network approach to prioritize conservation efforts for migratory birds
Habitat loss can trigger migration network collapse by isolating migratory bird breeding grounds from nonbreeding grounds. Theoretically, habitat loss can have vastly different impacts depending on the site’s importance within the migratory corridor. However, migration-network connectivity and the impacts of site loss are not completely understood. We used GPS tracking data on 4 bird species in the Asian flyways to construct migration networks and proposed a framework for assessing network connectivity for migratory species. We used a node-removal process to identify stopover sites with the highest impact on connectivity. In general, migration networks with fewer stopover sites were more vulnerable to habitat loss. Node removal in order from the highest to lowest degree of habitat loss yielded an increase of network resistance similar to random removal. In contrast, resistance increased more rapidly when removing nodes in order from the highest to lowest betweenness value (quantified by the number of shortest paths passing through the specific node). We quantified the risk of migration network collapse and identified crucial sites by first selecting sites with large contributions to network connectivity and then identifying which of those sites were likely to be removed from the network (i.e., sites with habitat loss). Among these crucial sites, 42% were not designated as protected areas. Setting priorities for site protection should account for a site’s position in the migration network, rather than only site-specific characteristics. Our framework for assessing migration-network connectivity enables site prioritization for conservation of migratory species. La pérdida del hábitat puede disparar el colapso de las redes de migración al aislar los sitios de reproducción de las aves migratorias de aquellos sitios que no se usan para la reproducción. En teoría, la pérdida del hábitat puede tener impactos muy diferentes dependiendo de la importancia del sitio dentro del corredor migratorio. Sin embargo, la conectividad entre las redes de migración y los impactos de la pérdida de los sitios no están del todo comprendidos. Usamos los datos de seguimiento por GPS de cuatro especies de aves en las rutas de vuelo de Asia para construir redes de migración y propusimos un marco de trabajo para evaluar la conectividad de las redes en las especies migratorias. Usamos un proceso de extracción de nodos para identificar los sitios de escala con el mayor impacto sobre la conectividad. En general, las redes de migración con menos sitios de escala fueron más vulnerables a la pérdida del hábitat. La extracción de nodos en orden del grado más alto al más bajo resultó en un incremento de resistencia de la red similar a la extracción al azar. Al contrario, la resistencia incrementó más rápidamente cuando la extracción de los nodos fue en orden del más alto al más bajo valor de intermediación (cuantificado por el número de caminos más cortos que pasan por un nodo específico). Cuantificamos el riesgo de colapso de la red de migración e identificamos sitios cruciales al seleccionar primero los sitios con mayores contribuciones a la conectividad de la red y después identificar cuáles de esos sitios tenían probabilidad de ser removidos de la red (es decir, sitios con pérdida de hábitat). Entre estos sitios cruciales, el 42% no estaban designados como áreas protegidas. El establecimiento de prioridades para la protección de un sitio debería considerar la posición del sitio dentro de la red de migración, en lugar de sólo considerar las características específicas del sitio. Nuestro marco de trabajo para la evaluación de la conectividad de la red de migración permite la priorización de sitios para la conservación de las especies migratorias. 栖息地丧失导致的迁徙鸟类繁殖地和非繁殖地隔离会引发迁徙网络的瓦解。理论上,取决于该栖息地在 迁徙廊道里的重要性,不同栖息地节点的丧失会对迁徙网络造成不同的影响,但目前对迁徙网络连通性以及栖 息地丧失对迁徙网络影响的理解还不完善。本研究基于亚洲迁徙路线上4 种迁徙鸟类物种的 GPS 追踪数据,分 别构建了迁徙网络并提出了衡量迁徙物种迁徙网络连通性的方法体系。我们使用节点去除法来确定高重要性中 途停歇地。具有较少停歇地的迁徙网络通常受栖息地丧失的威胁更严重。我们发现,依据栖息地丧失程度由高 到低的顺序去除栖息地,迁徙网络阻力的增加趋势与随机去除栖息地结果基本一致。而如果依据栖息地节点的 中间值(表征通过该节点的最短路径数量)由高到低的顺序去除栖息地节点,迁徙阻力则呈现快速上升。我们 量化了迁徙网络瓦解的风险并基于栖息地节点对迁徙网络连通性的贡献和节点的脆弱性(栖息地退化程度)识 别了关键栖息地。其中 42% 的关键栖息地处于非保护地状态。我们建议设定栖息地优先保护级别时需要考虑 该栖息地在迁徙网络中的位置和作用,而不是仅依据该栖息地的本身特征。本研究提出的栖息地网络连通性评 价体系为迁徙物种栖息地优先保护提供了重要理论和方法依据。
Meta-Analytic Review of Corridor Effectiveness
Using corridors for conservation is increasing despite a lack of consensus on their efficacy. Specifically, whether corridors increase movement of plants and animals between habitat fragments has been addressed on a case-by-case basis with mixed results. Because of the growing number of well-designed experiments that have addressed this question, we conducted a meta-analysis to determine whether corridors increase movement; whether corridor effectiveness differs among taxa; how recent changes in experimental design have influenced findings; and whether corridor effectiveness differs between manipulative and natural experiments. To conduct our meta-analysis, we analyzed 78 experiments from 35 studies using a conservative hierarchical Bayesian model that accounts for hierarchical and sampling dependence. We found a highly significant result that corridors increase movement between habitat patches by approximately 50% compared to patches that are not connected with corridors. We found that corridors were more important for the movement of invertebrates, nonavian vertebrates, and plants than they were for birds. Recent methodological advances in corridor experiments, such as controlling for the area added by corridors, did not influence whether corridors increased movement, whereas controlling for the distance between source and connected or unconnected recipient patches decreased movement through corridors. After controlling for taxa differences and whether studies controlled for distance in experimental design, we found that natural corridors (those existing in landscapes prior to the study) showed more movement than manipulated corridors (those created and maintained for the study). Our results suggest that existing corridors increase species movement in fragmented landscapes and that efforts spent on maintaining and creating corridors are worthwhile.
Digital Communication Engaged in by Spanish Associations of Social Workers in Social Networking Sites: Coalition, Hierarchisation, or Isolation? Comunicación digital de los Colegios de Trabajo Social en España en las redes sociales online: ¿coalición, jerarquización o aislamiento?
In a context of accelerated digital transformation, social networking sites have changed the strategies used in organisational communication. In this article, netnography and socia lnetwork analysis are used to analyse the connectedness, interaction, and leadership processes engaged in by Spanish associations of socialworkers in online social networks, specifically Facebook and Twitter. Algorithms were used to detect communities that form communication structures that determine the dynamics of cooperation and cohesion. The results show a strongly hierarchical communication structure, where communities tend to closure. Based on the results obtained, a series of strategies are presented to improve the cooperation between the Spanish associations of socialworkers in social networking sites.
On how much biodiversity is covered in Europe by national protected areas and by the Natura 2000 network: insights from terrestrial vertebrates
The European Union has made extensive biodiversity conservation efforts with the Habitats and Birds Directives and with the establishment of the Natura 2000 network of protected areas, one of the largest networks of conservation areas worldwide. We performed a gap analysis of the entire Natura 2000 system plus national protected areas and all terrestrial vertebrates (freshwater fish excluded). We also evaluated the level of connectivity of both systems, providing therefore a first estimate of the functionality of the Natura 2000 system as an effective network of protected areas. Together national protected areas and the Natura 2000 network covered more than one‐third of the European Union. National protected areas did not offer protection to 13 total gap species (i.e., species not covered by any protected area) or to almost 300 partial gap species (i.e., species whose representation target is not met). Together the Natura 2000 network and national protected areas left 1 total gap species and 121 partial gap species unprotected. The terrestrial vertebrates listed in the Habitats and Birds Directives were relatively well covered (especially birds), and overall connectivity was improved considerably by Natura 2000 sites that act as stepping stones between national protected areas. Overall, we found that the Natura 2000 network represents at continental level an important network of protected areas that acts as a good complement to existing national protected areas. However, a number of problems remain that are mainly linked to the criteria used to list the species in the Habitats and Birds Directives. The European Commission initiated in 2014 a process aimed at assessing the importance of the Birds and Habitats Directives for biodiversity conservation. Our results contribute to this assessment and suggest the system is largely effective for terrestrial vertebrates but would benefit from further updating of the species lists and field management.
Toward Best Practices for Developing Regional Connectivity Maps
To conserve ecological connectivity (the ability to support animal movement, gene flow, range shifts, and other ecological and evolutionary processes that require large areas), conservation professionals need coarse-grained maps to serve as decision-support tools or vision statements and fine-grained maps to prescribe site-specific interventions. To date, research has focused primarily on fine-grained maps (linkage designs) covering small areas. In contrast, we devised 7 steps to coarsely map dozens to hundreds of linkages over a large area, such as a nation, province, or ecoregion. We provide recommendations on how to perform each step on the basis of our experiences with 6 projects: California Missing Linkages (2001), Arizona Wildlife Linkage Assessment (2006), California Essential Habitat Connectivity (2010), Two Countries, One Forest (northeastern United States and southeastern Canada) (2010), Washington State Connected Landscapes (2010), and the Bhutan Biological Corridor Complex (2010). The 2 most difficult steps are mapping natural landscape blocks (areas whose conservation value derives from the species and ecological processes within them) and determining which pairs of blocks can feasibly be connected in a way that promotes conservation.Decision rules for mapping natural landscape blocks and determining which pairs of blocks to connect must reflect not only technical criteria, but also the values and priorities of stakeholders. We recommend blocks be mapped on the basis of a combination of naturalness, protection status, linear barriers, and habitat quality for selected species. We describe manual and automated procedures to identify currently functioning or restorable linkages. Once pairs of blocks have been identified, linkage polygons can be mapped by least-cost modeling, other approaches from graph theory, or individual-based movement models. The approaches we outline make assumptions explicit, have outputs that can be improved as underlying data are improved, and help implementers focus strictly on ecological connectivity. Para conservar la conectividad ecologica (la habilidad para soportar movimiento de animales, flujo de genes, cambios de rango de distribucion y otros procesos ecológicos y evolutivos que requieren áreas extensas), los profesionales de la conservación necesitan mapas de grano grueso que sirvan como herramientas de soporte para la toma de decisiones y mapas de grano fino para recomendar intervenciones en sitios especificos. A la fecha, la investigación se ha centrado principalmente en mapas de grano fino (diseño de conexiones) que abarcan areas pequeüas. En contraste, diseüamos 7 pasos para hacer mapas de grano grueso de docenas hasta centenas de conexiones en un área extensa, como un pais, provincia ecorregión. Proporcionamos recomendaciones de cómo llevar a cabo cada paso con base en nuestrasexperiencias con oproyectos: Conexiones Faltantes en California (2001), Evaluatión de la Conexión de Vida Silvestre en Arizona (2006), Conectividad de Hábitat Esencial de California (2010), Dos Paises-Un Bosque (noreste de Estados Unidos y sureste de Canadá) (2010), Paisajes Conectados del Estado de Washington (2010), y el Complejo del Corredor Biologico de Bután (2010). Los dos pasos mas difidles son el mapeo de los bloques de paisaje natural (áreas donde el valor de conservatión se dériva de las especies y sus procesos ecológicos) y la déterminatión de los pares de bloques que son factibles de conectarse de manera que promueva la conservatión. Las réglas de decisión para el mapeo de bloques de paisaje natural y la déterminatión de cuales pares de bloques sern conectados debe reflejar no solo criterios técnicos, sino también los valores yprioridades de los actores involucrados. Recomendamos que los bloques sean mapeados con base en una combination de naturalidad, estatus de protection, barreras lineales, y calidad del habitat para especies selectas. Describimos procedimientos manualesy automatizados para identificar las conexiones restaurables ofuncionales actualmente. Una vez que los pares de bloques han sido identificados, lospoligonos de conexion pueden ser mapeados por modelaje de costo minimo, otros métodos de teoria dégrafas modelos de movimiento basados en individuos. Los métodos que delineamos hacen suposiciones explicitas, tienen resultados que pueden ser mejorados a medida que mejoran los datos subyacentes y ayudan a que los implementadores se concentren estrictamente en la conectividad ecologica.
Connectivity of wood thrush breeding, wintering, and migration sites based on range‐wide tracking
Many migratory animals are experiencing rapid population declines, but migration data with the geographic scope and resolution to quantify the complex network of movements between breeding and nonbreeding regions are often lacking. Determining the most frequently used migration routes and nonbreeding regions for a species is critical for understanding population dynamics and making effective conservation decisions. We tracked the migration of individual Wood Thrushes (Hylocichla mustelina) (n = 102) from across their range with light‐level geolocators and, for the first time, quantified migration routes and wintering regions for distinct breeding populations. We identified regional and species‐level migratory connectivity networks for this declining songbird by combining our tracking results with range‐wide breeding abundance estimates and forest cover data. More than 50% of the species occupied the eastern wintering range (Honduras to Costa Rica), a region that includes only one‐third of all wintering habitat and that is undergoing intensive deforestation. We estimated that half of all Wood Thrushes in North America migrate south through Florida in fall, whereas in spring approximately 73% funnel northward through a narrow span along the central U.S. Gulf Coast (88–93°W). Identifying migratory networks is a critical step for conservation of songbirds and we demonstrated with Wood Thrushes how it can highlight conservation hotspots for regional populations and species as a whole.
Potential Negative Ecological Effects of Corridors
Despite many studies showing that landscape corridors increase dispersal and species richness for disparate taxa, concerns persist that corridors can have unintended negative effects. In particular, some of the same mechanisms that underlie positive effects of corridors on species of conservation interest may also increase the spread and impact of antagonistic species (e.g., predators and pathogens), foster negative effects of edges, increase invasion by exotic species, increase the spread of unwanted disturbances such as fire, or increase population synchrony and thus reduce persistence. We conducted a literature review and meta‐analysis to evaluate the prevalence of each of these negative effects. We found no evidence that corridors increase unwanted disturbance or non‐native species invasion; however, these have not been well‐studied concerns (1 and 6 studies, respectively). Other effects of corridors were more often studied and yielded inconsistent results; mean effect sizes were indistinguishable from zero. The effect of edges on abundances of target species was as likely to be positive as negative. Corridors were as likely to have no effect on antagonists or population synchrony as they were to increase those negative effects. We found 3 deficiencies in the literature. First, despite studies on how corridors affect predators, there are few studies of related consequences for prey population size and persistence. Second, properly designed studies of negative corridor effects are needed in natural corridors at scales larger than those achievable in experimental systems. Third, studies are needed to test more targeted hypotheses about when corridor‐mediated effects on invasive species or disturbance may be negative for species of management concern. Overall, we found no overarching support for concerns that construction and maintenance of habitat corridors may result in unintended negative consequences. Negative edge effects may be mitigated by widening corridors or softening edges between corridors and the matrix. Other negative effects are relatively small and manageable compared with the large positive effects of facilitating dispersal and increasing diversity of native species.