Why do Goldfinches Turn Golden?
This is a particularly interesting time to watch American goldfinches, though I enjoy having them around all year long. But right now is when they do a partial molt, replacing all their feathers except for those on the wing and tail. The feathers that grow in are the bright yellow breeding plumage.
In September the goldfinches molt again, this time replacing all their feathers, but now they turn to a relatively drab olive color. Here’s a link with more details on the molting cycle of male goldfinches.
Birds like goldfinches and cardinals use bright colors to attract mates. But why don’t goldfinches keep their breeding plumage all year, as the cardinals do? The answer apparently lies in the cardinals’ much lengthier breeding season, which can run from February to September. In other words, goldfinches believe that once you’re done with all that romantic nonsense it’s time to grow up and settle down, while the cardinals are always ready for action.
But what about male goldfinches that don’t have the brightest plumage but have really great personalities? Can the female goldfinches really be so shallow?
Apparently a brighter color is a good indicator of general health and strength. Research on cardinals indicates that the most brightly colored males have the greatest reproductive success, hold better territories, and offer more parental care. In other words, the flashy ones are also the best providers AND they help out more with the kids.
You can attract goldfinches to your feeders with nyjer and sunflower seed. It’s important to keep the nyjer fresh, even if it means throwing out uneaten leftovers (which can be hard to do because the stuff is expensive).
But goldfinches can also be attracted with garden plants, including sunflowers (Helianthus sp. and cvs.), purple coneflowers (Echinacea purpurea), anise hyssop (Agastache foeniculum), cup plant (Silphium perfoliatum) and just about any of the Rudbeckias. In late summer I enjoy watching the goldfinches feasting on the seeds of these plants.
Do you see goldfinches at your feeder or in your garden?