Tree swallow (Tachycineta bicolor) August 3, 2020 1800 × 1200 Tree swallow (Tachycineta bicolor) Tree Swallow (Tachycineta bicolor), August 2015, Napeague. “Staging” for migration. Breeder. Mid-August, 2015. Napeague, Long Island. Breeder. As they get ready to migrate south. They will descend on bayberry bushes to fuel up on the berries.