During the spring and summer months in the Arb, birds are building their nests and raising their young. After the chicks have fledged, many birds abandon their nests and build a new one the next year. For this reason, you can find empty nests throughout the Arb during the winter! 

Birds are very particular about how they build their nests: the size, materials used and the shape of the nest are all particular to each bird species. That being said, it is often extremely difficult to determine the species that made a nest you might see. There is variation between individual birds, and materials will vary within the species’ range. However, there are a few nests that are very distinctive.

The nest of the American Goldfinch is usually quite easy to identify. Goldfinches nest later in the year (June–August) when milkweed and thistle are blossoming. These plants have seeds which have a fluffy tuft attached, with which the Goldfinches will line the inside of their nests. Look for downy material when trying to identify a nest! Goldfinches build their nests in shrubs or sapling trees, usually in more open spaces rather than in dense woodland. 

Gray Catbirds also have a distinctive nest, with a layer of dense twigs, bark, straw and mud, and an inner layer of grass, rootlets, hair and pine needles. It is very common for there to be a color difference between the outside and inside: the inside will have a darker color, whereas the outside will have a lighter color. Catbirds build their nest in dense shrubs. Luckily the foliage of most shrubs in the arboretum has fallen to the ground: look out for these nests in shrubs which may normally be too thick to peer inside.

Even though most of these nests will be abandoned right now, please do not disturb the nests or take them from the original spot. A picture and admiration works best!