It’s not that I like ice Or freezin’ winds and snowy ground. It’s just sometimes it’s kind of nice To be the only bird in town.
This final post on our January Yellowstone trip shares a few highlights of the birds we encountered. There are certainly way fewer birds in this frozen land in winter, though the thermal features do keep some waterways open for the few waterfowl that remain (or gather there in winter, in the case of Trumpeter Swans). And the activities of wolves and the bottleneck of cold and food limitations do provide sustenance for the avian scavengers – the eagles, magpies, and ravens. Here are a few bird highlights from the trip…
Recent surveys have estimated there are 200-300 ravens utilizing the northern part of the park as habitat. They are frequently seen near areas of concentrated human activity (pit stops, favorite pullouts, etc.) where they are very clever at taking advantage of any potential food items left unguarded. They are also abundant at any carcass, be it a roadkill or wolf kill.
The sight of Ravens wearing mini-backpacks (satellite transmitters) really peaked my curiosity. The one above was photographed at Tower Junction near the pit toilets and trash/recycling bins. We saw another one (maybe more) flying back and forth with chunks of meat at the bison carcass where we watched the wolves. When I got home I started searching for more information about this study, the Yellowstone Raven Project. The goal is to have about 70 ravens tagged in the park, all wearing solar-powered GPS backpacks with an antenna that submits the birds’ locations every 30 minutes throughout the day. Using this data, researchers are able to piece together the movement of Ravens from sunrise to sunset. There are many things they are investigating about these highly intelligent birds (how do Ravens consistently find wolf kills?; how far do they travel daily/monthly/yearly,?; where are they roosting?, etc.). I contacted Dr. Marzluff, the lead scientist, this week and asked about the Raven above, as I could not find the color code combination of leg bands on the Animal Tracker app, (this free app allows you to peek in on the movements of various tagged animals around the world, including the Yellowstone Raven Project). He promptly responded to let me know that this bird, a female, was captured and tagged on December 10, 2021, at Tower Junction, and has not yet been added to the app. In fact, he was watching that bird the day I emailed him! I’ll try to follow up with him in a few weeks to see what this bird has been up to. It is really amazing to be able to follow research going on in the park (and there is a lot of it!).
One of the more unusual bird interactions was with a roadkill Ruffed Grouse. We passed it and Melissa radioed me asking if that thing in the road was an animal or just a mud blob or other inanimate object. I wasn’t sure, so when we came back through, I noticed it was, indeed, an animal. I radioed her and she stopped, exclaiming it was a bird, a grouse! We parked and everyone got out to do a spontaneous roadside necropsy. We saw the track trail of the bird approaching the road in the snow and then the tragic result. Melissa poked around and we could see the stomach contents, which included some rose hips (something I had ironically mentioned as a bird food source to the group on one of our snowshoe hikes when we passed one of the shrubs with its bright red fruit). This close up view also allowed us to admire the beautiful plumage and the amazing adaption of the bristles along the birds’ toes which act like grouse-sized snowshoes. Another unique Yellowstone teachable moment!
One of my favorite birds in the park, anytime of year, is the American Dipper. I sat along the river one day watching one feed from the edge of the ice.
I reviewed 7 video clips I made of athe dipper feeding and the average time spent underwater was 6 seconds (five 6’s, a 5, and a 7). The dipper was successful in bringing up a prey item in all seven instances. All were small invertebrates with the exception of one decent-sized macroinvertebrate that I think was a stonefly larva.
So, why do dippers dip? There are a few theories out there: 1) the repetitive bobbing against the backdrop of turbulent water may help conceal the bird’s profile from predators; 2) dipping in this and some other birds may helps it sight prey; 3) the one that an Audubon article I ran across thinks is the most likely is that dipping and the rhythmic batting of those bright white eyelids is a mode of visual communication with other dippers in their typically noisy environment where the usual calls might not be easily heard.
We also saw several other species that evaded a decent photo including Common Redpoll, Gray-crowned Rosy Finch, Black-billed Magpie, Pine Grosbeak, Hairy Woodpecker, Clark’s Nutcracker, Gray Jay, and Red-breasted Nuthatch, Mallard, and Trumpeter Swan.
Thanks for following our winter adventure. Can’t wait to go back!