The first full weekend of 2017 proved to be quite eventful indeed. I was up early on Saturday morning so I could record my observations of the birds that arrived at my feeders. This is pretty standard for a winter weekend, and there was nothing really all that unusual to report. The temperature was a respectable 14 degrees, the sun was playing peekaboo with the clouds and the community of birds was perfectly predictable.
What wasn’t predictable, in any way, was the observation I made around lunchtime. I was at the writing desk next to my kitchen window, and I was looking out onto the deck. A surge of activity was underway, and I wanted to see if I could get an accurate count of how many birds were out there. You see, in addition to keeping track of the species that I see, I also keep track of the number of each species that I see.
There were 11 juncos, 16 goldfinches, 3 red-breasted nuthatches, 5 white-throated sparrows … the list is actually rather extensive. It was while I was trying to get these accurate counts that I saw something that struck me as particularly odd. A unknown bird with unknown markings was at the railing. For the life of me, I couldn’t figure out what I was looking at until I finally grabbed my binoculars and focused on the mystery bird. I was flabbergasted by what I saw.
It was a black-capped chickadee, but it was an individual exhibiting a condition known as “leucism.” This results in patches of skin (or in the case of birds the feathers) that have a complete lack of pigmentation. Thus, the black-capped chickadee that I was looking at was more of a mottled black-and-white capped chickadee, and it simply looked wrong.
In a “regular” chickadee, the eyes are surrounded by black feathers. The bottom edge of the black “cap” actually aligns pretty closely with the bottom of the eye, which means that you never really see the eye contrasting against lighter feathers. On the leucistic chickadee, however, about 50 percent of the black cap was white. This gave the bird an unsettling moth-eaten appearance, and it actually gave my camera quite a bit of trouble. The camera’s “brain” simply couldn’t decide what to focus on, which made taking photos an unusual challenge, considering how close the bird was.
The sudden appearance of the bird hinted at the complex social lives of chickadees. In the fall, young chickadees disperse out into the landscape and they have two options: they can either become somewhat permanent members of a stable flock, or they can become what are known as “winter floaters.” In her wonderful book, “The Black-Capped Chickadee,” Susan Smith explains that “stable flocks” of chickadees can consist of a single mated pair up to five or six mated pairs.
In late autumn, when the flocks first start to form, the numbers are almost always in multiples of two, and the sex ratios in the flocks are almost always one-to-one. That being said, winter is a very stressful and dangerous time for all birds, and some may die of disease or predation. This opens the door for other birds to join a stable flock, thus encouraging at least some movement in an area that might cover the adjacent territories of several stable flocks. Some of the birds that wander, or float, are young birds, while others might be senior birds looking to better their positions by joining new flocks.
On Jan. 7, even before I noticed the leucistic chickadee at my porch railing, I could see that an atmosphere of relative calm in the chickadees at my feeders had given way to a more animated, energetic, even hostile atmosphere. The flock at my feeders consists of four chickadees this winter, and they are comfortable in each other’s presence. That all changed with the arrival of a fifth bird. Lots of angry chasing started to occur, and all of the birds seemed agitated. The leucistic chickadee would represent the sixth bird (maintaining Smith’s one-to-one ratio), and along with it arrived a somewhat animated, hyperactive tone.
In the past, I’ve suspected that certain birds at my feeders “know” me and feel comfortable around me. I’ve also been pretty sure that I can point to certain days when new birds have suddenly appeared, because their attitudes toward me are so much different that those I have cultivated throughout the summer. The problem is that, as a species, chickadees look so similar that I can’t trust in my own ability to recognize individuals by sight alone. The leucistic individual, however, stands out like a sore thumb.
This bird returned to the feeders Jan. 8 and spent the entire day zipping in to grab sunflower seeds, then flying off to the south somewhere out of sight. Because I work during the week, I won’t be able to determine if the leucistic chickadee persists at my feeders until Jan. 14, which is after I’ve submitted my column, but it will be very interesting no matter what the outcome is. If the bird hangs around, is it because it found my feeders, or is it because it found a place in a stable flock? If the bird disappears, on the other hand, does that say anything negative about my feeders, or does it suggest that a good food source isn’t as good as a rambling life or a spot in a different flock?
Keep your eyes peeled for new developments at your own feeders. Lots of science has been done to understand these birds, but that doesn’t mean you can’t engage in your own observations and independently make the same discoveries. Learning about the natural world has been the great joy of my life, and I am convinced that turning off the screens and looking out at the real world will help everyone live a calmer, more interesting life. Give it a try!
Bill Danielson has worked for the National Park Service, the US Forest Service, and the Massachusetts State Parks. He has been a professional writer and nature photographer for 19 years and he also teaches high school biology and physics. Visit www.speakingofnature.com for more information, or go to Speaking of Nature on Facebook.