Unlike many birds, goldfinches molt their body feathers twice a year: in the spring before breeding and after nesting in the fall. Females are a soft olive green and subdued yellow. Males sport vibrant, yellow coats with black wings, caps and tails during breeding season, but in the fall, they molt into duller colors that resemble the female.
The color of the legs, feet and bill of an American Goldfinch change with each feather molt. For breeding season, their legs, feet and bill are a buffy, yellow-orange color. During fall and winter, their legs, feet and bill are dark grayish-brown.
The spring molt requires a large amount of nutrients and energy which probably diminishes their ability to nest earlier in the season. Another reason Goldfinches nest late is because the native thistle plant bears food sources as well as nesting material. The plant is ready in July. After the male has serenaded the female with canary-like songs in late July or early August, goldfinches begin to nest for the first and only time of the year.
Here are a few items to remember when attracting finches:
- Keep food fresh and dry inside the feeder. Shake the feeder
periodically to make sure that the food is dry, and use a Weather Guard
to help protect your food from the elements. Make sure the food does not
stay in the feeder uneaten for more than three
to four weeks.
- Nyjer has a lot of protein and fat that is needed for growing their feathers. Be prepared for increased activity at your feeders in the spring and fall, when goldfinches are molting.
- Once they've fledged, young goldfinches still depend on their parents for food. Watch for these juveniles at your feeders as they beg for food from their parents.
- Due to their almost exclusive diet of seeds, goldfinches drink frequently and will stay close to reliable sources of water during dry periods. Use a bird bath and keep the water clean and fresh.
Source: WBU Nature News