2016 Faves—Passerines, part 11: Y

End with a flourish,” I’ve read. So here goes.

The “Y” birds (Y not, you may ask) include three birds whose names begin with Yellow. One, the Yellow-headed Blackbird is a western bird.The other two, warblers, are found across the North American continent and coast to coast to coast in Canada.

Yellow-headed Blackbird – Version 2
Yellow-headed Blackbird puts his foot down!

Yellow-headed Blackbirds return to us from the southwestern US and Mexico in early April. Occasionally, they’ll land on a rooftop on their way further north, but their season starts for us when we see the first males in Thomson Marsh where the Red-winged Blackbirds by this time are already well established. The first few males are very quiet; we’re likely to see them before we hear them. Within a couple of weeks, the situation reverses, and we enjoy the cacophony of the clash of vocalizing RWBLs and YHBLs. As with RWBLs, YHBL females show up a couple of weeks after the males have established their territories.

I confessed in part 3 of this series that my favourite species in the summer marsh is the Eastern  Kingbird. The Yellow-headed Blackbird is a close second. The chief difference and factor that makes me lean to the EAKIs is that individual families are much easier to identify among the EAKIs. The pairs are devoted to each other in ways that the YHBLs are not. The YHBLs arrive earlier than the EAKIs and depart earlier, as well, at least the males. By late summer, the marsh is ruled by the RWBLs and the growing EAKI families. But last year, at least, I was able to identify a couple of females that continued hang around. Their offspring seem to become independent fairly quickly. It was surprising to find a couple of female YHBLs still being chased by a fledgling Brown-headed Cowbird that had “conned” one of them into raising. Although they’re not very attractive/photogenic at this time of year, I find “Yellow-heads” an interesting group to study….

From Yellow-headed Blackbird, Identification, All About Birds – Cornell Lab of Ornithology [with some editing by KAR]:

With a golden head, a white patch on black wings, and a call that sounds like a rusty farm gate opening, [male] Yellow-headed Blackbirds demand our attention. Look for them in western and prairie wetlands, where they nest in reeds [or cattails] directly over the water. 

[We don’t get to see them winter in Kelowna, but we do run into migrating flocks in Kane Valley early in the spring.] They’re just as impressive in winter, when huge flocks seem to roll across farm fields. Each bird gleans seeds from the ground, then leapfrogs over its flock mates to the front edge of the ever-advancing troupe.

Yellow-headed Blackbirds breed in loose colonies, and males mate with several females. During the breeding season, they eat insects and aquatic invertebrates. [See map for wintering grounds.] They form huge flocks in winter, often mixing with other species of blackbirds, and feed on seeds and grains in cultivated fields. 

 

yellow-rumped-warbler-in-spring
Springtime Butterbutt, Belmont Pond

 

Well, we’re quickly nearing the end of this final chapter of Favourite Passerine Fotos of 2017. Let’s talk about two of the warblers that we look forward to every year in Belmont Park and ponds and Thomson Marsh: I’ll take them in the order in which they appear, which means we look first at Yellow-rumped Warblers, another bird that’s distributed across the NA continent and coast to coast to coast in Canada.

Yellow-rumped Warblers are impressive in the sheer numbers with which they flood the continent each fall. Shrubs and trees fill with the streaky brown-and-yellow birds and their distinctive, sharp chips. Though the color palette is subdued all winter, you owe it to yourself to seek these birds out on their spring migration or on their breeding grounds. Spring molt brings a transformation, leaving them a dazzling mix of bright yellow, charcoal gray and black, and bold white.” (Cornell)

The first year here, I waited expectantly and failed to find many close enough to photograph well. In 2016, however, I learned where to locate them—closer to home, ironically, and am looking forward to similar opportunities this spring. In summer, the Butter Butts pretty much leave town and the heat of the valley bottom for the cooler hillsides. In autumn, in their new camouflage, they reappear along with Warbling Vireos and juvenile Waxwings in various locations, along the Creek, but also among the many weeds now offering their seeds and harbouring insects….

These photos are not outstanding, but may indicate the kinds of interesting challenges that Yellow-rumps offer in the waning months of the year. By late October, they’re gone.

The final bird of this long series is the Yellow Warbler. I’ve learned to be patient with this  species. It appears in different locations at different times from  spring through early autumn. Early and late summer into autumn afford the best photo opps in the Okanagan. YEWAs can be very difficult to capture due their rapid movement and propensity for cover, but I can usually count on excellent chances late in the season….

Two of the shots below are of males. I’ll leave it to you to figure out which is which.

Click the photos to see them enlarged.

Yellow Warblers forage along slender branches of shrubs and small trees, picking off insect prey as they go or briefly hovering to get at prey on leaves. Singing males perch near the tops of the bushes or trees in their territory.

As male Yellow Warblers are setting up territories they may perform a “circle flight” in which they fly toward a neighboring male or female in a horizontal, semicircular path. A male may also fly slowly with fast, exaggerated wingbeats away from a female he is courting or a male he is competing with. As these territorial encounters proceed, males start by singing at each other; as the dispute goes on, the songs get quieter or switch to chip notes as the males begin to chase each other.

Yellow Warblers typically form monogamous pairs that sometimes last more than one breeding season and reform the next. Yellow Warblers defend their nesting territories from many species, including other warbler species, chickadees, House Wrens, blackbirds, and Eastern Kingbirds. They may even chase off other warbler species while on their wintering grounds. Common predators of Yellow Warbler nests include garter snakes, red squirrels, jays, crows, raccoons, weasels, skunks, and domestic or feral cats.” (Cornell)

And finally, a note on conservation with regards to YEWAs, again from Cornell:

Yellow Warblers are one of the most numerous warblers in North America but their populations have been slowly declining, and have decreased by 25% between 1966 and 2014, according to the North American Breeding Bird Survey. Partners in Flight estimates a global breeding population of 90 million with 37% spending some part of the year in the U.S., 15% in Mexico, and 57% breeding in Canada. They rate a 6 out of 20 on the Continental Concern Score and are not on the 2014 State of the Birds Watch List. In the western U.S. the grazing of rangelands can degrade Yellow Warbler nesting habitat, particularly stands of willow trees along creeks. The Brown-headed Cowbird lays its eggs in the nests of many species including Yellow Warblers, and this can reduce their breeding success. Like many migratory songbirds that move at night, Yellow Warblers are at risk of collisions with buildings; they can be attracted to and killed at tall, lighted structures such as TV towers and tall buildings.” We all hope this delightful, beautiful, interactive songster is able to survive in its Okanagan breeding grounds for years to come!

 

 

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