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Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Recent conservation plans for long-distance Neotropical migrant birds have emphasized the importance of understanding the ecology and threats facing a species throughout its life cycle, including migration and overwintering periods. To better understand the ecology of Broad-winged Hawks (Buteo platypterus) during the nonbreeding period, we followed the movements of 14 hawks from 2 breeding populations during July 2014-April 2019 to their overwintering sites. Three juvenile and 8 adult female Broad-winged Hawks were satellite-tracked from Pennsylvania, USA, and 3 adults (2 females and 1 male) were tracked from Alberta. Canada. We documented pre-migratory movements (post-breeding) of 4 of the 14 individuals. Adults initiated fall migration on [bar.x] = 25 August [+ or -] 16.38 d and 2 of the 3 juveniles began fall migration on [bar.x] = 20 August [+ or -] 2 d. Adults had 1-12 ([bar.x] = 5.0 [+ or -] 3.5) stopovers in autumn that lasted for 1-24 d and juveniles had 2-5 ([bar.x] = 3.0 [+ or -] 1.7) stopovers that lasted 2-51 d. Adults from Pennsylvania spent the overwintering period in Nicaragua, Brazil, Peru, and Colombia (n = 8) whereas those from Alberta wintered in Suriname, Venezuela, and Bolivia (n = 3). The distance traveled on autumn migration was greater for Alberta birds ([bar.x]= 10,021 [+ or -] 866 km, n = 3) than for Pennsylvania birds ([bar.x] = 7,925 [+ or -] 1,631 km, n = 8). Migration distance and overwintering region varied by geographic origin with age but with some overlap between the 2 distinct geographic breeding populations. Broad-winged Hawks appear to follow a hybrid time--energy minimization strategy during fall and spring migrations with (1) energy minimization in North America, and (2) time minimization in Mexico and Central America. Stopover frequency, duration, and migration rate support this hypothesis. Received 11 July 2019. Accepted 18 February 2020. Key words: pre-migratory movements, raptor, satellite telemetry, stopover, travel rates, wintering areas Los planes de conservación recientes para aves migratorias neolropicales de larga distancia han cnfaüzado la importancia de entender la ecología y amenazas en enfrenta una especie a lo largo de su ciclo de vida, incluidas la migración y el periodo de invernada. Para entender mejor la ecología del gavilán Buteo platypterus durante el periodo no-reproductivo, seguimos los movimientos de 14 individuos de 2 poblaciones reproductivas durante julio 2014-abril 2019 a sus sitios de invernada. Tres juveniles y 8 adultos (2 hembras y 1 macho) fueron rastreados desde Pennsylvania, EUA, y 3 adultos (2 hembras y 1 macho) fueron rastreados desde Alberta, Canadá. Documentamos movimientos premigratorios (posreproductivos) de 4 de los 14 individuos. Los adultos iniciaron la migración otoñal en [bar.x] = 25 agosto [+ ó -] 16.38 d y 2 de 3 juveniles comenzaron su migración otoñal en [bar.x] = 20 agosto [+ ó -] 2 d. Los adultos tuvieron 1-12 ([bar.x] = 5.0 [+ ó -] 3.5) paradas de descanso en otoño que duraron de 1-24 d y los juveniles tuvieron 2-5 ([bar.x] = 3.0 [+ ó -] 1.7) paradas que duraron 2-51 d. Los adultos de Pennsylvania pasaron el periodo de invernada en Nicaragua, Brasil, Perú y Colombia (n = 8) mientras que aquellos de Alberta pasaron el invierno en Surinam, Venezuela y Bolivia (n = 3). La distancia de víaje en la migración de otoño fue mayor para las aves de Alberta ([bar.x] = 10,021 [+ ó -] 866 km. n = 3) que para las de Pennsylvania ([bar.x] = 7,925 [+ ó -] 1,631 km, n = 8). La distancia de migración y sitio de invernada variaron por origen geográfico según la edad, aunque con cierto traslape entre las 2 poblaciones reproductivas geográficamente diferentes. Estos gavilanes parecen seguir una estrategia híbrida de minmización de tiempo-energía durante sus migraciones de otoño y primavera con (1) minimización de energía en Norteamérica y (2) minimización de tiempo en México y Centroamérica. La frecuencia y duración de paradas de descanso, y la tasa de migración, apoyan esta hipótesis. Palabras clave: áreas de invernada, movimientos premigratorios, parada de descanso, rapaz, tasa de traslado, telemetría de satélite, Neotropical migrant birds have been the subject of conservation concern in recent decades due to the many threats occurring throughout the annual cycle, including migration, nonbreeding, and breeding periods (Greenberg [...]

For animals that produce species‐specific audible sounds, environmental recordings combined with automated acoustic monitoring software (passive acoustic monitoring [PAM]) may be an effective monitoring tool because it allows audio data from many, widely distributed autonomous recording units (ARUs) to be processed in a relatively short period of time. Males of many insect species produce loud, species‐specific mating songs, yet acoustic insects have received less attention from PAM relative to vertebrates.We evaluated the use of PAM to monitor, Roeseliana roeselii (Orthoptera, Tettigoniidae), an acoustic insect that has expanded its range to Alberta, Canada, far outside its naturalized North American range. We analysed environmental recordings from ARUs: (1) at two control sites known to be occupied by R. roeselii and (2) across Alberta established by the Alberta Biodiversity Monitoring Institute (ABMI) to search for new populations.PAM successfully detected R. roeselii at the two control sites, but not at any of the 73 ABMI sites that we analysed. Despite the failure to detect new locations of R. roeselii, our analysis of ABMI environmental recordings detected several other species of acoustic insects, including Orchelimum gladiator, Gryllus sp. and Allonemobius spp.Our results add to the growing body of work showing the feasibility of using PAM for acoustic insects. We make suggestions for how to maximize the effectiveness of this monitoring tool for the conservation and management of singing insects in North America. [ABSTRACT FROM AUTHOR]

Copyright of Ibis is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Given the substantial impacts of non-native species on invaded systems, an understanding of the rates and spatial patterns of invasive spread is critical. Spread may vary across spatial scales, with dispersal of invasive species occurring both via diffusive spread at local sites and long-distance jump dispersal at larger scales. Research on earthworm invasions in North American forests has focused on patterns of spread across landscapes, with less examination of spread at local sites. We sampled the exotic earthworm Dendrobaena octaedra (Savigny, 1826) on 500 m x 500 m grids at three sites in the boreal forest of northeastern Alberta in 2006 and again in 2012-2013 to examine distributional changes over time. Earthworms spread farther from roads (the presumed site of initial introduction) over time, and spatial patterns at our sites suggest transport by vehicles and waterways are key vectors of dispersal at the local level. Spread was estimated to be occurring at a rate of at least 17.9 m/year. Our study indicates that both diffusive spread and jump dispersal of earthworms can be important at local scales and that local diffusive spread may be substantially higher than previously estimated. Key words: boreal forest, Dendrobaena octaedra, earthworms, invasive species, local spread, spatial pattern, spread rate. Etant donne les impacts considerables des especes non indigenes sur les systemes envahis, la comprehension des taux et de la distribution spatiale de la dissemination envahissante est d'une importance critique. La dissemination peut varier selon l'echelle spatiale, la dispersion d'especes envahissantes s'effectuant tant par dissemination par diffusion a l'echelle locale que par dispersion par grands sauts a des echelles plus grandes. La recherche sur les invasions de lombrics dans les forets nordamericaines s'est axee sur les motifs de dissemination a l'echelle des paysages, s'interessant moins a la dissemination locale. Nous avons echantillonne du lombric exotique Dendrobaena octaedra (Savigny, 1826) sur des grilles de 500 m x 500 m en trois sites dans la foret boreale du nord-est de l'Alberta en 2006, puis en 2012-2013, afin d'examiner les variations de leur repartition dans le temps. La dissemination des lombrics s'eloignait des routes (sites presumes de l'introduction initiale) avec le temps, les motifs de repartition spatiale dans les sites etudies donnant a penser que les vehicules et les cours d'eau constituent des vecteurs cles de la dispersion a l'echelle locale. Il a ete estime que la dissemination s'effectuait a un taux d'au moins 17,9 m/an. Notre etude indique que tant la dissemination par diffusion que la dispersion par sauts des lombrics peuvent etre importantes a des echelles locales et que la dissemination locale par diffusion peut etre sensiblement plus importante que ce que laissaient croire les estimations passees. [Traduit par la Redaction] Mots-cles: foret boreale, Dendrobaena octaedra, lombrics, espece envahissante, dissemination locale, motif spatial, taux de dissemination., Introduction Information on the spread of non-native species is essential for predicting and managing invasions. However, determining rates of spread is challenging because data from multiple time points and across [...]

Copyright of Avian Conservation & Ecology is the property of Resilience Alliance and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Conservation approaches that efficiently protect multiple values, such as the umbrella species concept, have been widely promoted with expected dramatic ecosystem changes. Due to its social and cultural importance, and recent declining trends, boreal populations of woodland caribou have been suggested as potential umbrella species for other declining taxa, such as boreal landbirds. We propose a generic pixel‐based umbrella index that focuses on fine‐grained habitat overlaps. In light of ongoing conservation efforts worldwide implementing area‐based targets (e.g., 30% by 2030), we used a random neutral model as baseline, as opposed to a no‐conservation scenario, which has been used elsewhere. We found that the conservation efficiency of caribou as an umbrella for 71 co‐occurring landbirds—three of which are priority species—in the Northwest Territories, Canada, is generally lower than our random model, as 53% of the species presented negative umbrella index medians with the interquartile range not overlapping zero. We conclude that in cases where area‐based targets drive decision‐making and the issue at stake involves identifying which areas to conserve—not whether to conserve—woodland caribou may be a leaky umbrella for most co‐occurring landbird species and these might need complementary conservation actions to be brought in from the rain. [ABSTRACT FROM AUTHOR]