Yellow-rumped Warblers are hosting a convention outside our kitchen window. It’s pretty cool. They’re doing exactly as the book says, fluttering out from the mesquite trees to catch flying insects some days and other days skimming insects from above the surface of the resaca.
About 50 of the wee birds, barely bigger than a (large) butterfly, arrived unannounced one afternoon as I was staring out the window while washing dishes. One bird perched on a close branch and stayed still long enough for me to notice light brown streaks on its breast. Of course, my hands were in the water and the camera several rooms away.
Then I started seeing flashes of yellow from the masses as the birds sortied from trees to lawn and back again.
The birds are in their winter colors of pale brown with a splotch of bright yellow feathers on the lower back and side patches (armpits).
To heck with the dishes, I stepped outside to document the birds. With that tell-tale yellow, there’s no mistaking this species, but I wanted to be sure. The yellow glows like giant day-time fireflies in the grayness of our recent dreary days.
According to the bird book I use (Smithsonian Handbooks, Birds of Texas by Fred J. Alsop, III) — and three Websites: Allaboutbirds.org, Audubon.org, and Nationalgeographic.com — yellow-rumped warblers often perch on the outer limbs of trees and are very conspicuous as they fly out after insects, often making long, aerobatic pursuits and flashing their yellow rumps and white patches in the tail.
Back in the day, (prior to April 1973, to be exact) there was no species called yellow-rumped warbler. There were two separate species, the eastern Myrtle warbler and western Audubon warbler. Scientists lumped them based on evidence that the two species routinely hybridize in a narrow zone in western Canada.
Now, because of more advanced genetic testing, they soon may again be treated as two different species (and possibly four) and be rid of, as some birding authorities would like, the unflattering name of yellow-rumped warbler. I’d vote for being rid of that unfortunate name. Reference Kenn Kaufman 2016 Web article, http://www.audubon.org/news/the-yellow-rumped-warbler-will-probably-be-split-different-species-again
Our visiting warblers would classify as Myrtle warblers because of eye markings (white eyebrows and a white arc below the eye) and behavior.
Their feeding behavior is pretty versatile. They’ll forage on the ground, search among twigs and leaves and hover or cling to tree trunks and branches while taking insects from foliage. They also eat seeds from large and small weeds (we might say native plants).
Although insectivorous, they will readily take wax-myrtle berries in winter, a habit which gives the species its name.
If you aren’t familiar with common wax myrtle or Southern bayberry, (Morella cerifera; formerly Myrica cerifera) (I wasn’t) it’s native to South Carolina and other southeastern states from New Jersey to Florida and westward to Texas. It’s a very fast growing shrub used as screens, informal hedges, or roadside plantings. The foliage and berries are pleasantly aromatic. Birds are attracted to wax myrtles for food and shelter. In colonial times, the waxy berries were used for making candles.
Our yellow-rumped warblers are concentrating on insects. If they’re eating the Berlandier’s fiddlewood (Citharexylum berlandieri) fruit, it’s not within my viewing. According to various Website information, these warblers form small flocks on migration. In winter they often feed and travel in large flocks.
And that brings me to the boringness of the ever so over worked word used to describe a large number of birds — the word flock — reminding me it’s time to revisit the collective bird nouns. Stay tuned for the next blog post, please, for fun with words.