From a distance, the crow and common grackle look similar, but on closer inspection they're fairly easy to distinguish. As Mike O'Connor, author of Why Don't Woodpeckers Get Headaches, writes "it's like telling a sugar spoon from a soup spoon." Crows are large birds; the second largest songbird in the United States, dwarfed only by their cousin the raven. The common grackle, which shares the same family as blackbirds, cowbirds and orioles, is more than half the size of an American crow.
Crows average 11 to 13 inches tall, with a wingspan of 14 to 18 inches -- twice the wingspan of grackles. And at just under a pound, crows weigh nearly four times more than grackles. At first glance, both appear black, but in sunlight, grackles have a glossy and iridescent sheen of bronze, purple and green, especially on their heads. Unlike crows, grackles have bright yellow eyes. Crows are all black, from their feet to their beaks and everything in between. Like ravens and other members of the Corvidae family, crows are considered one of most intelligent birds.
Habitat and Range
The American crow is common throughout the continental United States, ranging as far as southern Canada. The common grackle lives year-round in nearly all states east of the Rocky Mountains. In the summer, many will migrate into Canada to breed. Both birds share common habitat preferences, including agricultural fields, suburban neighborhoods and city parks. Their abilities to thrive in urban and rural areas has led to both being targeted as pests.
Diet and Predators
Both crows and common grackles are omnivores, eating insects and small vertebrates including frogs and mice. Fruits, grains, nuts and garbage contribute to both birds' diets. Crows are often seen scavenging at the site of road-killed carcasses. Grackles feed heavily on corn; in fact they're the top threat to the crop. And because they feed primarily in large flocks -- unlike crows -- their impact can easily translate to millions of dollars. Both species are preyed upon by raccoons, snakes, owls, hawks, domestic cats and humans.
Grackles and crows form monogamous breeding pairs that share responsibilities for nest-building and care of the young. Crows lay larger and more eggs, averaging three to nine, compared to the grackle's one to seven. Crow eggs incubate as much as a week longer than grackle eggs. Once hatched, crow chicks stay in the nest 20 to 40 days, more than twice as long as grackle chicks at 10 to 17 days. In the wild, grackles upwards of 22 years, compared to the record 14 years for a wild crow.
- University of Michigan Museum of Zoology; Quiscalus Quiscula; Tanya Dewey
- University of Michigan Museum of Zoology; Corvus Brachyrhynchos; Cynthia Sims Parr
- The Cornell Lab of Ornithology: American Crow
- The Cornell Lab of Ornithology: Common Grackle
- The Cape Codder - Ask the Bird Folks: Crows & Grackles