It is also interesting to watch feeding during courtship and the feeding of young fledglings. The American goldfinch, Iowa's state bird ,will still be attracted to a thistle feeder, and by observing closely, bird watchers can see the males turn from their winter drab olive green to a striking yellow and black summer breeding plumage during this season. Most birds, however, are eating fruits and insects during this season. Although birds glean insects off leaves, bark, and the ground, insects are also a food source that can be provided for the birds during the summer. These insects not only supplement the birds' diet, but are also used for feeding their young.
Insects provide the necessary high sources of protein necessary for young birds to grow quickly.
One of the ways to provide insects is to raise or buy yellow mealworm. Mealworms can be purchased at pet stores or bait shops during the fishing season. You might also raise them in a container of oatmeal supplied with a small sliced potato on top for moisture. Another method is to catch some insects with a plastic bag under neath a plain fluorescent bulb or a black light placed outside at night with a sheet draped over it. Fruit also may be used to attract birds in the spring and summer.