Nombre en español: Pibí Occidental
Nombre en ingles: Western Wood-Pewee
Nombre científico: Contopus sordidulus
Familia: Tyrannidae
El pibí occidental (Contopus sordidulus) es una especie de ave paseriforme de la familia Tyrannidae que cría en el oeste de Norteamérica y pasa el invierno en Centro y Sudamérica.
Descripción
En promedio mide 14 cm de longitud y pesa 13,5 g. Las partes superiores son de color gris oliváceo, con la corona más oscura y las alas y la cola fuscas, con líneas grises en las alas; la garganta y el borde de las alas son de color blanco grisáceo; los lados del cuello, el pecho, los costados y los flancos son de color oliva claro y grisáceo; el vientre es blancuzco; la región infracaudal y el forro de las alas tienen la base grisácea y la punta blancuzca. El pico es negruzco, excepto el tercio basal que es amarillo a anaranjado opaco. Las patas son negras.
Su llamado es un zumbido fuerte chip; su canto consiste rápidos descendentes bziyir que puede alternar con tew ti dit terminando con un bziyir descendente.
Hábitat y ecología
Su hábitat de crianza son los bosques abiertos del oeste de Norteamérica. Al terminar el verano migra a Sudamérica a través de Centroamérica y las Antillas y pasa el invierno en los bordes de los bosques, bosques secundarios maduros y plantaciones de árboles, preferentemente entre los 1.200 y 3.000 m de altitud. Durante las migraciones una gran cantidad de individuos pueden ser observados juntos.
Alimentación
Se alimenta de insectos, principalmente moscas, hormigas, abejas, avispas y escarabajos, que atrapa en vuelo o espigando entre la vegetación.
Reproducción
Construye un nido en forma de cuenco en una horqueta de una rama horizontal7 o dentro de una cavidad de un árbol seco. Los bosques de roble negro de California son frecuentemente escogidos para anidar. La hembra pone 2 o 3 huevos y ambos padres alimentan los polluelos.
Western wood pewee
The western wood pewee (Contopus sordidulus) is a small tyrant flycatcher. Adults are gray-olive on the upperparts with light underparts, washed with olive on the breast. They have two wing bars and a dark bill with yellow at the base of the lower mandible. This bird is very similar in appearance to the eastern wood pewee; the two birds were formerly considered to be one species. The call of C. sordidulus is a loud buzzy peeer; the song consists of three rapid descending tsees ending with a descending peeer.
Habitat and ecology
Their breeding habitat is open wooded areas in western North America. These birds migrate to South America at the end of summer.[how often?] The female lays two or three eggs in an open cup nest on a horizontal tree branch or within a tree cavity; California black oak forests are examples of suitable nesting habitat for this species of bird. Both parents feed the young.
They wait on a perch at a middle height in a tree and fly out to catch insects in flight (hawking), sometimes hovering to pick insects from vegetation (gleaning).
An inhabitant of open forest, forest edge, and riparian zones, the Western Wood- Pewee is a widespread breeder in many of western North America’s forested habitats. Its generalized foraging behavior and nest site selection reflect its common occurrence. This species is primarily a sit-and-wait predator, sallying from open perches and usually returning to the same or a nearby perch in pursuit of flying insects, especially flies, ants, bees, wasps, and beetles. Its nest is usually placed in the fork of a horizontal branch, from near ground level to high up in living and dead trees. Both parents feed the young. Although an «acceptor» of Brown-headed Cowbird (Molothrus ater) eggs, this wood-pewee is generally an infrequent host of cowbirds.
The Western Wood-Pewee and the nearly identical Eastern Wood-Pewee (Contopus virens) are closely related, and along with the Tropical Pewee (C. cinereus), are regarded as a superspecies by some taxonomists. The Western and Eastern wood-pewees are separated by range, with small areas of overlap, and can be distinguished by vocalizations. Although common throughout its breeding range, many aspects of Western Wood-Pewee biology are not well known, especially its habits during migration and winter. Populations appear to be declining overall. This species may suffer from loss of riparian habitat in the United States andfrom unknown changes on migration and wintering grounds.
Fuentes: Wikipedia/eBird/xeno-canto/Neotropical Birds
