Vancouver Avian Research Centre

.....Research - Conservation - Education
Species: Bullock's Oriole Icterus bullockii
 

Description:

A characteristic bird of open woodland in western North America—especially riparian woodlands with large cottonwoods, sycamores, and willows—Bullock’s Oriole winters in western Mexico. In summer, this species eats mostly arthropods, readily augmenting its diet with ripe fruit.

Identification:

General: The Bullock’s Oriole is an icterid and member of the blackbird family. A bird of western North America the Bullock's Oriole is especially fond of open woodlands with tall trees along rivers and streams.

8 inches (20 cm) long, 36 gr. Medium-sized oriole: total length of males 17.2–19.3 cm; of females, 16.8–19.1 cm; mass 29–43 g. Sexually dimorphic in plumage and size, showing little, clinal geographic variation.

Adult Male: Black crown, nape eyeline, throat, back, wings and tail. Orange face, underparts and rump, and tail feathers. White wing patch and edges.Older males have bright black and orange-yellow plumage with black tip on tail.

Adult female: Green and yellow, with black on the throat. Grayish unpperparts, dull yellowish breast and undertail coverts, gray belly, two wing bars.

Juvenile: younger males resemble females, which are green and yellow, with black on the throat.

Similar Species: Baltimore Oriole Icterus galbula. Distinguished as Bullock’s develops black throat in male though hybridization occurs.

Behavior: Strong and direct flight, with complete wing-strokes. Makes short hops, often assisted by wings, when foraging in trees. Can hang upside down, clinging to branches for extended periods of time when foraging or building nest. Often flies to ground to pick up insects.

Habitat:

Spring and fall migration: found in variety of open woodlands and urban parklands and tall shrubland; sometimes in pine, pine-oak, or fir forests. Breeding: riparian and oak, especially where trees are large and well spaced or in isolated occasionally orchard trees usually near water. Nests commonly are placed in isolated trees, at edges of woodlands, along watercourses, in shelterbelts, and in urban parks. Several active nests may be placed in close proximity.

Information:

Bullock’s Oriole was described and named by William Swainson in 1827 on the basis of material collected by William Bullock and his son, also William. In his description, Swainson wrote, “This, the most beautiful of the group yet discovered in Mexico, will record the name of those ornithologists who have thrown so much light on the birds of that country” Bullock’s Oriole is less well studied than its eastern counterpart, the Baltimore Oriole.

Conservation Status:

Widespread and common the Bullock’s Oriole’s conservation status is currently listed as least concern (LC).
 
Capture Rates


Bullock’s Oriole breed commonly in the southern interior but rarely in the southwest coastal area of British Columbia. It is a rare visitor to Colony Farm as is reflected by the capture rate (2010-2012; standardized as birds captured per 100 net hours) of a few individuals in July and zero capture rate for the remainder of the year.

 

Home | About UsEducationResearch| Volunteer | About Birds | Gallery
 

Copyright 2008-2016 VARC - Designed by Derek Matthews. Administration by Mark Habdas