Despite their bright orange plumage, Baltimore orioles may not be easy to spot. These relatives of yellow-headed and red-wing blackbirds prefer high branches in densely wooded areas over open space like prairies. They tend to stay hidden, so you’re more likely to hear these birds than see them. They have a very rich, operatic, liquid-sounding whistling song, according to Abby Dean, a naturalist at Fullersburg Woods Nature Education Center in Oak Brook. "It really stands out," she said.