Common Grackle
Quiscalus quiscula
Adult common grackles measure from 28 to 34 cm (11 to 13 in) in length, span 36–46 cm (14–18 in) across the wings, and weigh 74–142 g (2.6–5.0 oz). Common grackles are less sexually dimorphic than larger grackle species, but the differences between the sexes can still be noticeable. The male, which averages 122 g (4.3 oz), is larger than the female, at an average of 94 g (3.3 oz). Adults have a long, dark bill, pale yellowish eyes, and a long tail; their feathers appear black with purple, green, or blue iridescence on the head, and primarily bronze sheen in the body plumage.
ID text from Wikipedia, CC BY-SA 4.0
Great-tailed Grackle
Quiscalus mexicanus
Great-tailed grackles are medium-sized birds (larger than starlings and smaller than crows; 38–46 cm (15–18 in) with males weighing 203–265 g (7.2–9.3 oz) and females 115–142 g (4.1–5.0 oz), and both sexes have long tails. Wingspan ranging 48–58 cm (19–23 in). Males are iridescent black with a purple-blue sheen on the feathers of the head and upper body, while females are brown with darker wings and tail. Adults of both sexes have bright yellow eyes, while juveniles of both sexes have brown eyes and brown plumage like females (except for streaks on the breast). Voice: Great-tailed grackles have an unusually large repertoire of vocalizations that are used year-round. The sounds range from "sweet, tinkling notes" to a "rusty gate hinge". Males use a wider variety of vocalization types, while females engage mostly in "chatter", however there is a report of a female performing the "territorial song".
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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