Tree swallow (Tachycineta bicolor) September 12, 2019 1500 × 1200 Tree swallow (Tachycineta bicolor) Tree swallow (Tachycineta bicolor). June 2018, Oceanside. Breeder; needs tree cavities or human-made nest boxes. June, 2018. Oceanside, New York. Common. Wet and dray grasslands.