Mahonias will make berries for the birds to eat. They bloom yellow this time of year and the berries come in the fall i think. they will grow in shade. Also hollies and aucuba will be evergeen, shade tolerant, and produce berries for the birds. any of these would be good as the background. good luck!
---Keith

Columbine attracts hummingbirds, masterwort (Astrantia) is popular with insects, maybe butterflies too, Lobelia cardinalis, a number of lilies if the shade isn't too thick, Pulmonaria and Bergenia for early season blooms beloved by hummingbirds...

While this seems shady, how much sun does it get? Even 6 hours of morning, early afternoon sun will allow you to plant some more sun loving plants than you might think. It is worth watching the area over the course of a day to calculate the # hours of sun.

Mahonias seed around a bit too much and pop up in unwanted places, I would not recommend them. However, birds do love sources of cover, so medium sized junipers would be nice (and they eat the berries). Hollies are another source of cover and berries. Depending on whether your neighbors have hollies (or you have others), you may need more than one as they are male and female plants. Another favorite shrub for birds is Spicebush (lindera benzoin), but you need male and female plants of those too.

If you expand the area beyond the dogwood, planting a serviceberry (amelanchier species) would be very popular. The birds love those berries. It is a small tree.

Until the plants get a little more mature, you may need to be content with providing cover and water and a supplemental source of food (a bird feeder).