August 2024 Natural Mystery Answered

We received eight correct answers to last month’s Natural Mystery—several of which included detailed information that went far beyond the scope of the question. It looks like many of you really know and love your feathers! Congratulations to Kirsten Welge, Alan Holzer, Ronnie Hartman, Mark McDermott, Collin Arnett, Maria Wesserle, Mike Holtz, and one anonymous naturalist for correctly identifying the original owner of these yellow-tipped feathers.

These are the tail feathers of a Cedar Waxwing.

I’d like to pass along some of the tips and process that people shared in arriving at their answers. Here is how Alan shared his process:

“The first step to ID-ing feathers is to know where on the bird's body the feathers came from. These feathers are strongly asymmetrical, which means they are feathers important for flight (either tail or primary wing feathers). These have a bit of a recurve to them, instead of one arcing curve—the right-most feather shows this most clearly. This is typical of tail feathers. These feathers show a consistent yellow tips, so next we must think about which birds around here in the summer have a yellow band at the end of their tail. There aren't many: Cedar Waxwings and Bohemian Waxwings fit the description and the size of the feathers shown, but I've never seen a Bohemian Waxwing here in the summer. The Fish and Wildlife Service's Feather Atlas also shows that Bohemian Waxwings have a slightly bigger yellow tip to the tail feathers.”


Mike followed a similar process, writing:

There is a bit of a curve to the shaft towards the bottom of the feather, but they are fairly straight after that, typical of some tail feathers. As opposed to primary feathers, which generally curve more along the whole feather. With tail feathers in mind, now we're looking for a bird with a yellow stripe across the end of a black tail. Cedar and Bohemian Waxwings both fit the bill in that respect, but Bohemian feathers would be a bit longer, and while they have been reported in the metro area, Cedar Waxwings are much more common.”


Collin Arnett used Bird Feathers by Scott and McFarland as his primary reference. He began by making a long list of birds with black-and-yellow coloring on their bodies, then measuring the feathers in the photo. Bird Feathers offers metric measurements, and Colin measured several of the feathers in the photo as between 5.9 and 6.0 cm. He shares:

“This size is too big for a Goldfinch and Yellow Warbler and a bit small for an oriole. It might fit the size for a redstart, but a redstart’s colors are reversed! It’s yellow at the base and black toward the end. Scott and McFarland’s photos of a Cedar Waxing feather show a dark gray vs black-based tail-feather with a striking yellow tip and sharp contrast between them measuring 6.1-6.2."

Colin then looked up Cedar Waxwings in Sibley’s guide to confirm that the habitat was a fit, and double checked his answer on the US Fish and Wilflife Service Feather Atlas.


Maria began with the Feather Atlas, using the Identify My Feather feature. She writes:

"Cedar Waxwing and Bohemian Waxwing were the two matching candidates. I immediately leaned toward cedar waxwing, as that is a fairly common bird in this area, whereas I have never seen a Bohemian Waxwing. They breed in northern Canada and Alaska and can be found in Minnesota during migration and winter. It's unlikely that they would be found near the Twin Cities in August. Furthermore, the size of the pictured feathers is a bit over 2.25" or 5.7cm. Since Bohemian Waxwings are slightly larger birds, their tail feathers are somewhat longer at 6.9cm - 7.3cm. Those of Cedar Waxing are listed as 6cm - 6.4cm, which are a better match for the feathers in the photo above."


Ronnie and Mark simply recognized the feathers based on their size and pattern.


Kirsten started off like Ronnie and Mark, by recognizing the feathers, then turned to the Feather Atlas to confirm her suspicions. She then continued to look further into this species and ask a couple of additional questions:

"On one Cedar Waxwing photograph on All About Birds, the caption noted the yellow tail band is influenced by diet; birds feeding on berries of exotic honeysuckle (Lonicera morrowii and Lonicera tataric) develop an orange band. A paper from 1992 discusses this phenomenon: in the eastern US, juvenile waxwings with orange tail tips have been observed within increasing frequency. Lonicera berries have become widely available during nesting season. These berries contain rhodoxanthin, a red pigment. In those areas, juveniles reared on a diet of Lonicera berries would show orange-tipped feathers. However, when adults typically molt their tail feathers, the berries are no longer available – so adults regrow yellow tail feathers. Interdependence!

 And that sparks a question: I see Lonicera shrubs all over Reservoir Woods and other forests in the Twin Cities area. I'm curious – have any local trackers observed orange-tipped Cedar Waxwing nestlings?"


A huge thanks to everyone who sent in an answer and shared your process with the rest of us. Congratulations again to Kirsten, Alan, Ronnie, Mark, Collin, Maria, and Mike.

Support the Newsletter

If you enjoy these natural mysteries, please consider supporting the Minnesota Wildlife Tracking Project newsletter on Patreon or buy me a coffee.