Estimates of productivity usually ignore survival during the postfledging period, the time between a bird's leaving its nest and departure for migration or movement to an area for wintering. During the first 1-3 weeks after fledging, young birds are limited in mobility, making them vulnerable to fatality, especially from prédation. To help fill this information gap, we examined the period of postñedging dependence of the Willow {Em-pidonax trailla) and Dusky {E. oberholseri) Flycatchers in the central Sierra Nevada, California. For fledglings we examined faetors that influenced survival, movements, and habitat use and home-range size. We observed family groups daily during the postfledging dependence period and resighted individual band combinations. Fledglings' survival ranged from 46% to 76% and varied by year and species. Fledglings moved on average 45 m from the nest per day during the dependence period. We detected family groups in their natal meadows from 13 to 33 days. We detected Willow Flycatchers in riparian shrubs 94% of the time, along the upland forest edge for the remaining 6%. We detected Dusky Flycatchers in riparian shrubs 70% of the time, in upland forest for the remaining 30%. For both years of our study combined, mean 95% home-range sizes were 1.80 ± 1.44 (SD) ha for the Willow Flycatcher and 1.82 ± 1.70 ha for the Dusky Flycatcher. Mean 50% core areas were 0.33 ± 0.27 ha for the Willow Flycatcher and 0.38 ± 0.44 ha for the Dusky Flycatcher. Supervivencia y Movimientos de Volantones de Empidonax trailla y E. oberholseriResumen. Los estimados de productividad usualmente ignoran la supervivencia durante el periodo posterior al emplumamiento, el tiempo entre que un ave deja el nido y que parte en migración o se mueve a un área para invernar. Durante las primeras 1-3 semanas luego de emplumar, las aves jóvenes tienen una movilidad limitada, haeiendo que sean vulnerables a una fatalidad, especialmente por depredación. Para ayudar a llenar este vacio de información, examinamos el periodo de dependencia posterior al emplumamiento en Empidonax trailla y E. oberholseri en la Sierra Nevada central. California. Para los volantones, examinamos los factores que influeneiaron la supervivencia, los movimientos, el uso de habitat y el tamaño del ámbito hogareño. Observamos diariamente grupos familiares durante el periodo de dependencia posterior al emplumamiento y realizamos observaciones repetidas de combinaciones individuales de anillos. La supervivencia de los volantones fluctuó entre 46% y 76% y varió por año y especie. Los volantones se movieron en promedio 45 m desde el nido por dia durante el periodo de dependencia. Detectamos grupos familiares en sus prados natales desde 13 a 33 dias. Detectamos la presencia de E. trailla en arbustos ribereños el 94% de las veces y a lo largo del borde del bosque en la zona alta no inundable el 6% restante. Detectamos a E. oberholseri en los arbustos ribereños el 70% de las veces y en las tierras altas no inundables el 30% restante. Combinando los dos años de nuestro ...

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The controversy over the use of null hypothesis statistical testing (NHST) has persisted for decades, yet NHST remains the most widely used statistical approach in wildlife sciences and ecology. A disconnect exists between those opposing NHST and many wildlife scientists and ecologists who conduct and publish research. This disconnect causes confusion and frustration on the part of students. We, as students, offer our perspective on how this issue may be addressed. Our objective is to encourage academic institutions and advisors of undergraduate and graduate students to introduce students to various statistical approaches so we can make well-informed decisions on the appropriate use of statistical tools in wildlife and ecological research projects. We propose an academic course that introduces students to various statistical approaches (e.g., Bayesian, frequentist, Fisherian, information theory) to build a foundation for critical thinking in applying statistics. We encourage academic advisors to become familiar with the statistical approaches available to wildlife scientists and ecologists and thus decrease bias towards one approach. Null hypothesis statistical testing is likely to persist as the most common statistical analysis tool in wildlife science until academic institutions and student advisors change their approach and emphasize a wider range of statistical methods.

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