I consider myself a very lucky person to have so many birds live out the daily events of their lives in such close proximity to my home. The secret, of course, is the endless supply of food that I provide for them in the feeders on my deck. With very few exceptions there is a daily morning feast awaiting any bird brave enough to come close to my house. I have to be very vigilant in bringing all of the feeders inside at night (to prevent raccoons and bears from ruining the party), but so far it has worked out very well.
On certain days in the winter, I can have more than 100 individual birds zooming around the deck as they scramble to gobble up as much breakfast as they possibly can. In the springtime, there is a noticeable shift in the community of birds that gather for their meals, with some of the regular customers checking out as they head north.
Other reservations are filled by birds arriving from points south to take up residence in their summer quarters. This sort of thing has already started, with the departure of the dark-eyed juncos and the arrival of the chipping sparrows. As the days roll on, more and more reservations will be filled and the number of birds species observed in my yard will swell from a low of 31 species in January to a high of 68 species in August.
But there is one “regular” resident in my yard that does a ‘disappearing act” without actually disappearing at all. It is the American goldfinch (Spinus tristis) and its change from the formality of its summer breeding plumage to a much more sedate set of winter clothes is so dramatic that sometimes people think that the goldfinches have vanished altogether. The reverse transition — from their sedate winter garb to the dazzling yellow of the breeding season — is currently underway, and I have had several males kindly cooperate by posing for photos.
The reason for the color change is quite simple. During the breeding season, a male American goldfinch advertises is health and vigor by donning a costume of bright, eye-catching yellow. His beak also turns a golden orange color that also displays his overall health. For a female goldfinch, a yellow male is simply irresistible.
In 1904, the naturalist John Burroughs described the transformation and said, “When the change in plumage is complete, and the males have got their bright uniforms of yellow and black, the courting begins. All the goldfinches of a neighborhood collect together and hold a sort of musical festival.” This is certainly happening in my yard as the males’ feathers switch over to yellow, but there are some awkward moments when the males look terribly ragged and moth-eaten.
Today’s photo was actually selected by my beautiful wife, Susan. It shows an adult male that is very close to the end of his color change with enough of the winter feathers still present to give him a patchwork appearance. In just another week or so, this male will have a solid black forehead and cap and a body that is solid yellow. For now, however, he still looks a bit rough.
The reason for the color change in winter is all about hiding from predators. A dazzling yellow bird would be much easier to see in the months when different shades of gray dominate the landscape. Additionally, the darker olive-brown feathers of their winter plumage are better at collecting heat from the winter sun. Yet another benefit is the calming of aggressive feelings. That bright yellow is a signal of a preparedness to fight, while the dull olive feathers promote more harmony among the winter flocks.
I have still seen a fair bit of quarreling and squabbling over food when groups of 30-40 goldfinches show up for breakfast at my feeders, but this is just a competition for food rather than all out war. The female goldfinches also change into yellow costumes for the breeding season, but their yellows are nowhere near as bright as those of the males. This is important for the females because they are the ones who are solely responsible for incubating the eggs in their nests.
Unlike many other species, the males are extremely attentive to their mates while they are occupied with their task of incubation. In his essay, “August Days,” Burroughs describes events that he witnessed near his study: “A goldfinches’ nest in the maple-tree near the window where I write, the female sitting on four pale bluish-white eggs; the male feeds her on the nest; whenever she hears his voice she calls incessantly, much after the manner of the young birds — the only case I recall of the sitting bird calling while in the act of incubation.”
By the end of August there will be a host of goldfinch fledglings following their fathers around the landscape and calling for food with the ridiculous frenzied panic and exuberance of youth. The young birds are a flat gray in appearance and by the time winter rolls around again, yet another costume change from the adults can make it quite difficult to tell the youngsters apart from their parents. Only careful observation, up close, will provide any hint of adulthood, but the goldfinches in my neighborhood are always close enough for me to tell.
Bill Danielson has been a professional writer and nature photographer for 28 years. He has worked for the National Park Service, the US Forest Service, the Nature Conservancy and the Massachusetts State Parks and he currently teaches high school biology and physics. For more information visit www.speakingofnature.com, Speaking of Nature on Facebook, or the Speaking of Nature Podcast.