If you've noticed the goldfinches in your yard looking a bit bedraggled, they're not sick, they're molting. In California and Oregon, both the American and and lesser goldfinches molt from August through October. They lose their bright breeding feathers and replace them with a more dull colors, giving them a patchy appearance as they grow in. Molting allows birds to replace worn or damaged feathers, which is a critical process. Feathers are not only responsible for flight, they also give birds weather protection making them virtually waterproof. Unlike many songbirds, goldfinches molt twice a year, so you'll have your brilliant yellow male back in the spring when he starts looking for a mate. Birds need extra protein and fat during molting, so you can help them out by offering quality bird seed. Seeds from big box stores are often extremely dried out giving the birds little nutritional value. Check dates on packaging and look for ingredients such as vegetable oil, which is often added to make seed appear fresher.