Every winter, many of Utah’s breeding birds migrate south to avoid the cold. After the warblers, tanagers, and orioles leave each fall, we share the snowy winter with hardier residents, such as chickadees, nuthatches, and juncos. But even hardier birds breed in the far north and venture south to Utah only during the most severe winters.
Many people are familiar with the high, thin calls of Cedar Waxwings. Less frequently heard in Utah are the slightly lower calls of their close cousins, Bohemian Waxwings.
Bohemian Waxwings are slightly larger than Cedar Waxwings, and a little fancier—their wing feathers include red, yellow, black, and white, and the underside of their tails is a rich cinnamon. Both species gather by the hundreds to eat berries, so you won’t miss a flock if there’s one nearby. Although waxwings are songbirds, the calls you hear don’t serve the same functions as true songs, advertising mate quality and defending territories. Instead, waxwings cooperate to find and feed on scattered fruit, their main winter diet. Unlike most birds, waxwings are able to smell, which may help them find their food. If waxwings eat berries that have begun to ferment over the winter months, they may become intoxicated even though their ability to metabolize ethanol is very high. The last time Bohemian Waxwings were abundant in Utah was during the winter of 2012-2013.
If you look in a pine tree, you may see a flock of White-winged Crossbills. Last abundant in Utah during the winter of 2008-2009, this species of finch forages on the seeds inside of conifer cones. As the name crossbill suggests, the lower part of its bill is bent to the right and the upper part to the left, allowing crossbills to wedge open pinecone scales and lift the seeds free with their tongues. In the winter, crossbills forage in flocks of ten to fifty. They quickly assess the quality of a tree’s cones, using visual and vocal cues from their flockmates, which are quiet when they are eating but chatter when they are not. When the volume of the chatter increases to a crescendo, all the crossbills in the flock know that it’s time to switch to a new tree. Unlike most songbirds, crossbills can breed at any time of year, as long as conifer seeds are abundant.
When the weather gets cold, keep an eye and an ear out for these winter nomads.
For Wild About Utah, I’m Andrew Durso.
Waxwing Images: Courtesy US FWS, David Menke, Photographer
White-winged Crossbill Image: Courtesy and Copyright © 2009 Paul Higgins, Photographer
Text: Andrew Durso, http://www.biology.usu.edu/htm/our-people/graduate-students?memberID=6753
Fitting the Bill, Andrea Liberatore, August 11, 2011, http://wildaboututah.org/fitting-the-bill/
White-winged Crossbill, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/White-winged_Crossbill/id
Cedar Waxwing, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Cedar_Waxwing/id
Bohemian Waxwing, All About Birds, Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Bohemian_Waxwing/id