Great-tailed Grackle

The Great-tailed Grackle (Quiscalus mexicanus) is a large, highly intelligent member of the icterid family (New World blackbirds). Known for its dramatic appearance, bold behavior, and incredible adaptability, this species has undergone a rapid and massive range expansion over the last century, spreading from its historic range in Mexico and the Gulf Coast deep into the American West, Midwest, and Pacific Northwest. They are highly social birds, often seen in large, noisy flocks, particularly in human-dominated environments such as city parks, strip malls, and agricultural areas.

Identifying the Great-tailed Grackle is easiest when noting their severe sexual dimorphism, distinct tails, and bright eyes.

Males: Large, measuring up to 46 cm. Fully adult males are a striking, glossy black with a rich violet-blue iridescent sheen across the back and breast in direct sunlight. Their most defining feature is an enormous, keel-shaped tail that they can fold into a V-shape. They possess piercing, bright yellow eyes.

Females: Considerably smaller (about half the weight of males) and altogether different in coloration. Females are brown, with a darker back and wings, a warm buff-colored breast and throat, a dark line through the eye, and a pale yellow or light brown eye.

Similar Species to Distinguish:

• Boat-tailed Grackle (Quiscalus major): Nearly identical. Where their ranges overlap along the Texas and Louisiana Gulf Coast, check eye color. Boat-tailed Grackles in this zone typically have dark eyes, whereas Great-tailed Grackles have bright yellow eyes. The crown shape also differs slightly: Great-tailed has a flatter crown, while Boat-tailed has a more rounded profile.
• Common Grackle (Quiscalus quiscula): Noticeably smaller with a much shorter, less dramatic tail and a different distribution (primarily eastern/central North America).

Great-tailed Grackles are exceptionally adaptable but generally favor open areas with some water and scattered trees. They have thrived in human-altered landscapes, making themselves at home in agricultural fields, pastures, orchards, suburban parks, and urban parking lots (particularly near supermarkets or restaurants where food waste is abundant). Historically native to Central America and Mexico, their range now extends across most of the western and central United States. While most populations in the southern parts of their range are permanent residents, those nesting at the northern limits in the Great Plains and Pacific Northwest may migrate south for the winter.

Vocalizations: This species is legendary for its loud, chaotic, and incredibly varied acoustic repertoire. Their calls consist of a bizarre mix of mechanical-sounding clicks, high-pitched squeals, metal-on-metal scrapes, whistles, and low-frequency rattles.

Foraging: Outstandingly opportunistic omnivores, they forage on the ground, in shallow water, and even in trees. They eat insects, spiders, snails, frogs, lizards, small fish, bird eggs, grains, fruit, and human refuse.

Social and Breeding: These are highly colonial birds. In the spring, males establish small territories within a single tree and perform elaborate displays to attract multiple females. The most famous is the 'bill-up' display, where two males stand close together, point their bills straight to the sky, and freeze to assert dominance. Breeding pairs assemble bulky cup nests made of twigs, grass, and mud. In the winter, they gather in colossal communal roosts that can number in the tens of thousands of individuals, creating a deafening evening chorus.