Did you know that songbirds need our help? It is estimated that 1/3 of our native birds have been lost in the last 30 years. It's pretty obvious that humans have take over a big chunk of bird habitat. Invasive plant species are doing the same in the "wild."
Invasives may provide a home and a bit of food for birds, but not in the same way that native species do. Remember that birds, insects, and plants have all evolved together and are ideally suited to provide for one another. Invasives do not support the insects that birds eat during their spring migrations. In the fall, their berries do not provide the right nutrition birds need. Birds stop to rest and eat when they need to, and will eat whatever is available, regardless if it has enough energy to power them to their next stop. Birds that do not migrate also make use of the berries that persist during winter. Most of us enjoy songbirds in our yards, but do not have nearly enough plants to support them. In fact, some plants like nandina are actually poisonous to birds (if you have them, remove all berries before they can be eaten). If you are looking to add some shrubs to your landscape, consider adding some that support wildlife like migratory birds. Ideal shrubs for our area (based on nutritional value of the berries) are arrowood vibernum (Vibernum dentatum), spicebush (Lindera benzoin), gray dogwood (Cornus racemosa), and red osier dogwood (Cornus sericea stolonifera). Other valuable options are elderbery (Sambucus canadensis), blueberry (Vaccimium), serviceberry (Amelanchier arborea), red winterberry holly (Ilex verticillata), virginia creeper (Parthenocissus quinquefolia), northern bayberry (Myrica pensylvanica), pokeweed (Phytolacca americana), and chokeberry (Photinia pyifolia). Source: Susan Smith Pogano, "Native Fruiting Plants for Migratory Bird Nutrition" presentation Dec. 2019 CCLC Conference