Birds of the Glebe, Goldfinch
The male Goldfinch grows bright yellow breeding plumage in the early spring and loses it again in the autumn.
Photo: Jeanette Rive
A Flash of yellow
By Jeanette Rive
A flash of yellow and black. Squabbling in small flocks around the feeder. Swooping bouncy flight, flitting in and out of bushes and trees, calling as they fly.
That’s the male American Goldfinch, such a colourful addition to the songbirds in our gardens. Goldfinches are migratory birds but have certainly spent winters in our area when it’s not too cold and there is access to their favourite food: sunflower and nyjer seeds.
It’s easy to focus on the impressive, easily visible larger birds around us, but our small birds pack so much colour and character into a tiny 12-gram body. If you get the chance to see a little warbler or finch up close, you’ll realize how tiny they are, between 11 and 13 cm – and a real challenge for photographers! The female and non-breeding male are a duller olive green and light brown. The male grows the bright yellow breeding plumage in the early spring and loses it again in the autumn. All birds molt once or twice a year, growing new feathers to stay warm, dry and airborne, and most small songbirds have a complete molt in late summer. They can look a little shaggy and dishevelled as the new feathers grow in.
The Goldfinch may be a common visitor to our gardens and feeders but it has several individual characteristics. They are almost exclusively vegetarian and will only swallow insects inadvertently. This means that when a parasitic bird – one that lays its eggs in another bird’s nest to be incubated and fed by someone else, such as the Brown-headed Cowbird – the imposter chick will not survive because it needs insects to thrive. Goldfinches also breed later than most songbirds, as late as July when their preferred food – milkweed, thistle and other plants – have produced their fibrous seeds not just to eat but also for the fibres that are used to build the nests.
The nest is cup shaped, suspended between small tree branches, about 10 cm across and about six to eight cm deep. It’s built out of small roots, plant fibres woven tightly together and bound with spider silk and fluffy fibres. It takes the female about six days to create her nest and it is so waterproof that chicks have been known to drown in the nest if they are not shielded from the rain by the mother. Once the nest has been built, the Goldfinch pair leave the area for as long as two weeks, making it appear as though the nest has been abandoned, but they eventually return! Three to six light blue eggs, about one cm in size, are laid and incubated solely by the female for about 12 to 14 days. To ensure they all hat
ch at the same time, she only starts incubating once the last egg has been laid. The male will bring food for her and the chicks until they leave the nest after about 12 days. The chicks weigh only about one gram at birth and gain ten times their weight by the time they fledge!
Once fledged, they are fed by the male for the next few weeks while the female flies off to find another mate to raise a second brood – that’s another unusual trait, as most birds only raise one brood a year.
After the nesting season is over, the Goldfinches regroup into their little flocks again and we can see them flitting around our gardens, calling out. Some birders think the song sounds like they are saying po-ta-to-chip very quietly!
Jeanette Rive is a Glebe bird enthusiast and Glebe Report proofreader with an eye for error.