Late winter and early spring bring so many colors to the Central Valley: White almond blossoms, pink peach blooms, dark green valley oak leaves and in the sky, flashes of brilliant orange.
Bullock’s orioles (Icterus bullockii) have made their way from southwestern Mexico to local wildland and backyard trees to find a mate and raise a new generation of the bird. The male of the species is bright orange overall with a black cap, a streak of black through its eyes and white wing patches. It arrives here in advance of the female which is colored a dull gray and orange overall.
Soon to follow on its migratory trip north will be the smaller and more slender hooded oriole (Icterus cucullatus), its males sporting brilliant yellow to flame orange feathers that extend like a hood from the neck to the top of its head, a black throat patch and white wing bars. Female hooded orioles are an olive yellow color with light gray feathers on their backs.
A third species, the streak-back oriole (Icterus pustulatus) also nests in the valley from time to time but it is seen far less frequently than its two cousins. As the name implies, streaks of black and orange feathers adorn the back of the bird.
Orioles of all species eat insects. The Bullock’s prefers gleaning bugs while hanging upside down in tree canopies while the hooded bird favors hunting insects in low to mid-level trees and shrubs but also while inverted.
The birds also enjoy nectar from flowers and juice from ripe fruit. They are often seen at backyard hummingbird feeders sampling some of their smaller feathered friends’ sugar water.
Bullock’s orioles prefer building their hanging nests in large cottonwood trees but will also nest in sycamores, willows and deciduous oaks, as long as the trees are large. While the canopies of our native woodlands are their preferred neighborhoods, they can also be found in orchards, parks and oak woodlands.
Hooded orioles prefer more exotic greenery when it comes to nest building. Females will often stitch their nest to the underside of palm fronds earning the bird its moniker “the palm-leaf oriole.” Its preference for nesting in palm trees creates a conundrum for the flashy bird since it tries to remain unseen while going about its daily affairs but lives where palm trees are most prevalent: urban neighborhoods.
Orioles have long, pointed and very strong bills. They are members of the blackbird family as are cowbirds and meadowlarks. They use their powerful bills to open flowers, dig into ripe fruit or expand the opening in tree bark to get at hidden insects and grubs. Bullock’s orioles will extract and discard the stinger from honey bees before consuming the buzzers. Beetles, ants, grasshoppers, spiders, larvae and caterpillars are all on an oriole’s bill of fare.
Backyard oriole feeders often attract the birds. They seem to remember where those feeders are year-to-year and will return to them each migration. However, they appear to be an unforgiving species because if the feeder they return to is empty when they first arrive after a long flight from Mexico, the birds tend not return to that feeder for the rest of the season. No dough, no show.
The San Luis National Wildlife Refuge, Merced National Wildlife Refuge and the San Joaquin River National Wildlife Refuge comprise the San Luis National Wildlife Refuge Complex. Its headquarters and visitor center are located just north of Los Banos off Highway 165 at 7376 South Wolfsen Road.
The refuges are open to visitors daily from one half-hour before sunrise to one half-hour after sunset. The visitor center is open Monday through Friday except federal holidays from 8 a.m. to 4:30 p.m.
