North American Bird Bander Jul-Sep 2016 Vol. 41 No. 4
Feature Articles
An Efficient and Inexpensive Apparatus for Collecting Fecal Samples During Banding Studies: Revisiting an Underutilized Technique
Patrick J. Ruhl, Jameson M. Pierce and John B. Dunning, Jr.
Abstract- Using fecal samples to analyze trophic levels, glucocorticoids, and diet of birds is common in avian research. However, several methods of fecal sample collection often do not provide a complete sample and can induce unnecessary stress in birds. Parrish et al. (1994) described a new fecal sampling apparatus to opportunistically collect feces of mist-netted birds. However, based on the paucity of citations for this method, it appears that it has not been widely accepted or implemented in field studies. In this paper we describe a modification of the fecal sampling apparatus outlined in Parrish et al. (1994), and suggest that this technique eliminates many of the shortcomings associated with other common methods of fecal sample collection. Our compact fecal sampling apparatus is constructed using inexpensive materials and can be implemented in many banding studies, including remote operations. In the summer of 2016 we tested the efficacy of this fecal sampling apparatus on 99 passerines of three species (44 Worm-eating Warblers (Helmitheros vermivorum), 29 Ovenbirds (Seirus aurocapillus), and 26 Scarlet Tanagers (Piranga olivacea). Eighty birds successfully defecated in the apparatus (31 Worm-eating Warblers, 26 Ovenbirds, and 23 Scarlet Tanagers), resulting in an 81% success rate for this method. We deem this technique highly effective and recommend its implementation in future banding studies that incorporate a fecal sampling research component.
Avian Morphometric Data from a Long-term Bird Banding Effort in North Texas
Douglas R. Wood, Phillip J. Leonard, Benjamin P. Singleton, Kristin L. Brooks, Ashley B. Carraghan, Bobby R. Long
Abstract- Morphometric data can be useful in determining age and sex of bird species that exhibit regional variation. We analyzed morphometric data from 12,834 individuals of 58 species banded at a long-term banding station in North Texas from 1978-2014. Mean wing length, tail length, and body mass are reported for resident and migrant birds banded in this flyway. For 20 species, males had longer mean wing length; in 14 species males had longer mean tail length, and for 3 species males had greater mean body mass than females. For 12 species, adult birds had longer wing length, tail length or body mass than younger birds.
Influence of Audio Lures on Capture Rates of Passerines During Spring Migration in Veracruz, Mexico (La Influencia del Uso de Atrayentes Auditivos Sobre Niveles de Captura de Paserinas Durante la Migración de Primavera en Veracruz, México)
Marcel A. Gahbauer, Cyndi M. Smith, Manuel Grosselet and Georgita Jane Ruize Michael
Abstract- We studied the effect of audio luring on a selection of passerine birds during spring migration at Minatitlán, Veracruz, Mexico, in 2013. At our MIGRA2 site we broadcast an audio lure daily over a period of one month, while at our CONTA3 site the same audio lure was broadcast every second day. Of the five species broadcast throughout the study period, three were significantly more numerous at CONTA3 on audio lure days (Swainson’s Thrush, Yellow-breasted Chat, and Painted Bunting), and Yellow Warbler, numbers were non-significantly higher, whereas Common Yellowthroat was marginally more numerous on silent days. Six other common species (≥ 25 individuals banded) were also more numerous on audio lure days although their calls were not part of the broadcast. Among the five species on the audio lure throughout the study period, capture frequencies varied by age and sex, although not consistently across species. Stopover frequency and duration were both very low. Use of audio lures may be particularly valuable where higher capture rates can increase the power of trend estimation. Further studies should explore additional target species to improve our understanding of audio lure effectiveness, and replicating this work in different locations would help assess variability in response of individual species.
Resumen- Se estudió el efecto de atrayentes auditivos en una selección de aves paserinas durante la migración de primavera de 2013, en Minatitlán, Veracruz, México. En nuestro sitio de monitoreo MIGRA2, emitimos un atrayente auditivo diariamente durante un period de un mes, mientras que en nuestro sitio CONTA3 el mismo atrayente fue transmitidio cada dos días. De las cinco especies cuyos cantos y llamados fueron transmitidos en todo el período de studio, tres fueron significativamente más numerosas en CONTA3 (Zoral de Swainson’s, Buscabreña y Siete Colores), en tanto que los Chipes amarillos no fueron significativamente más altos, y los Chipes garganta amarilla fueron marginalmente más abundantes en días silenciosos. Otras seis especies communes (≥ 25 individuos anillados) también fueron más numerosas durante los días de emission a pesar de que sus cantos no formaron parte de lo transmitido. En las cinco especies que formaron parte del atrayente auditivo durante el período de studio, las frecuencias de captura variaron según la edad y sexo, aunque no de manera consistente en todas estas especies. La duración y frecuencia de las “paradas” fueron muy bajas. El uso de atrayentes auditivos puede ser particularmente valioso en donde las tasas altas de captura pueden aumentar el poder de las estimación de tendencia. Nuevos estudios deberían explorer en otras especies con el fin de mejorar nuestro entendimiento sobre la efectividad del uso de atrayentes auditivos, y su replicación en diversas localidades ayudaría a evaluar la variabilidad en la respuesta de especies individuales.