33 research outputs found

    A Survey for Federally Listed Grassland Birds at First Nations Reserves

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    We surveyed native and non-native grassland for federally listed grassland bird species at Reserves and/or Treaty Land Entitlements (TLE) belonging to five First Nations in the prairie ecozone of Canada. Ferruginous Hawk (Buteo regalis – of special concern), Loggerhead Shrike (Lanius ludovicianus – threatened), and Long-billed Curlew (Numenius americanus – of special concern) were observed at five of 335, three of 361, and five of 329 survey points within their respective geographic ranges. Sprague’s Pipit (Anthus spragueii – threatened) was observed at 69 of 361 survey points and accounted for 84% of sites with listed birds. Estimates of proportions of native and non-native grassland within 400 m of survey points indicated that Sprague’s Pipit preferred native grassland. Despite special effort, the Burrowing Owl (Athene culicularia – endangered) was not observed, although a nest from a previous year was encountered. We recorded the greatest number of species and individuals on reserves located in mixed and moist-mixed grasslands that contained large portions of native grassland. In many instances, field assessments revealed unsuitable habitat at sites that remote-sensing data classified as suitable

    Influence of vegetation on the nocturnal foraging behaviors and vertebrate prey capture by endangered Burrowing Owls

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    Restrictions in technology have limited past habitat selection studies for many species to the home-range level, as a finer-scale understanding was often not possible. Consequently, these studies may not identify the true mechanism driving habitat selection patterns, which may influence how such results are applied in conservation. We used GPS dataloggers with digital video recorders to identify foraging modes and locations in which endangered Burrowing Owls (Athene cunicularia) captured prey. We measured the coarse and fine-scale characteristics of vegetation at locations in which owls searched for, versus where they caught, vertebrate prey. Most prey items were caught using hover-hunting. Burrowing Owls searched for, and caught, vertebrate prey in all cover types, but were more likely to kill prey in areas with sparse and less dense vegetative cover. Management strategies designed to increase Burrowing Owl foraging success in the Canadian prairies should try to ensure a mosaic of vegetation heights across cover types

    Off-road sampling reveals a different grassland bird community than roadside sampling: implications for survey design and estimates to guide conservation

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    Grassland bird species continue to decline steeply across North America. Road-based surveys such as the North American Breeding Bird Survey (BBS) are often used to estimate trends and population sizes and to build species distribution models for grassland birds, although roadside survey counts may introduce bias in estimates because of differences in habitats along roadsides and in off-road surveys. We tested for differences in land cover composition and in the avian community on 21 roadside-based survey routes and in an equal number of adjacent off-road walking routes in the grasslands of southern Alberta, Canada. Off-road routes (n = 225 point counts) had more native grassland and short shrubs and less fallow land and road area than the roadside routes (n = 225 point counts). Consequently, 17 of the 39 bird species differed between the two route types in frequency of occurrence and relative abundance, measured using an indicator species analysis. Six species, including five obligate grassland species, were more prevalent at off-road sites; they included four species listed under the Canadian federal Species At Risk Act or listed by the Committee on the Status of Endangered Wildlife in Canada: Sprague's Pipit (Anthus spragueii), Baird's Sparrow (Ammodramus bairdii), the Chestnut-collared Longspur (Calcarius ornatus), and McCown's Longspur (Rhynchophanes mccownii). The six species were as much as four times more abundant on off-road sites. Species more prevalent along roadside routes included common species and those typical of farmland and other human-modified habitats, e.g., the European Starling (Sturnus vulgaris), the Black-billed Magpie (Pica hudsonia), and the House Sparrow (Passer domesticus). Differences in avian community composition between roadside and off-road surveys suggest that the use of BBS data when generating population estimates or distribution models may overestimate certain common species and underestimate others of conservation concern. Our results highlight the need to develop appropriate corrections for bias in estimates derived from roadside sampling, and the need to design surveys that sample bird communities across a more representative cross-section of the landscape, both near and far from roads

    Fitomejoramiento participativo, evaluación y colección de materiales de maíz criollos en el Municipio de San Pedro Pinula, Jalapa, Guatemala, C.A.

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    La presente investigación se realizó en el Municipio de San Pedro Pinula, Jalapa, Guatemala, mediante el diagnóstico realizado a la producción del cultivo de maíz se encontró que en el área, el cultivo es poco tecnificado debido a la falta de asistencia técnica e introducción de tecnología. Es por ello que se realizó una colección de materiales de maíz criollos de la región para su posterior evaluación y así poder encontrar variedades que mejor se adapten a los sistemas de producción del área y las condiciones climáticas adversas que se presentan, debido a que el cultivo es exclusivamente de temporal. También se determinó que el flujo genético a nivel local constituye el principal elemento que facilita la obtención de semilla a nivel de comunidad, ya que el 94% de los agricultores utilizan semilla local, esto nos da a entender la importancia que tienen los sistemas locales de producción de semillas en la seguridad alimentaria de la comunidad. La aplicación de metodologías de Fitomejoramiento Participativo son de vital importancia debido a que el mismo agricultor forma un papel determinante en la evaluación de las variedades, posibilitando disponer de mayor información para la toma de decisiones en la selección, implementación y desarrollo de nuevas variedades. De los materiales evaluados bajo condiciones de estrés hídrico se presentaron algunas variedades mejoradas por el ICTA con rendimientos hasta de 5000 kg/ha y algunas variedades locales con rendimientos entre 3000 y 3500 kg/ha, cabe destacar que estos materiales locales superaron en rendimiento a variedades mejoradas como ICTA B-1, ICTA B-5 e ICTA B-7 en un 47%, posiblemente debido a una mejor adaptabilidad a las condiciones climáticas. Es importante disponer de información de los materiales locales, que en un futuro pueden ser la base para el desarrollo de nuevas variedades que eleven el rendimiento actual

    A Survey for Federally Listed Grassland Birds at First Nations Reserves

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    We surveyed native and non-native grassland for federally listed grassland bird species at Reserves and/or Treaty Land Entitlements (TLE) belonging to five First Nations in the prairie ecozone of Canada. Ferruginous Hawk (Buteo regalis – of special concern), Loggerhead Shrike (Lanius ludovicianus – threatened), and Long-billed Curlew (Numenius americanus – of special concern) were observed at five of 335, three of 361, and five of 329 survey points within their respective geographic ranges. Sprague’s Pipit (Anthus spragueii – threatened) was observed at 69 of 361 survey points and accounted for 84% of sites with listed birds. Estimates of proportions of native and non-native grassland within 400 m of survey points indicated that Sprague’s Pipit preferred native grassland. Despite special effort, the Burrowing Owl (Athene culicularia – endangered) was not observed, although a nest from a previous year was encountered. We recorded the greatest number of species and individuals on reserves located in mixed and moist-mixed grasslands that contained large portions of native grassland. In many instances, field assessments revealed unsuitable habitat at sites that remote-sensing data classified as suitable
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