How to identify the Great-tailed Grackle

To correctly identify the Great-tailed Grackle (Quiscalus mexicanus), check each of these features. Birds can be tricky: habit, habitat, and call often confirm a sighting that a single photo cannot.

Size at a glance

Length

33-46 cm (13-18 in)

Wingspan

40-52 cm (16-20.5 in)

Weight

88-265 g (3.1-9.3 oz)

Physical features to check

1. 1

   Plumage

   Overall feather coloration and pattern.

   Adult males are entirely iridescent black, appearing purple-blue to green in strong light. Adult females are smaller, duller, and typically dark brown on the upperparts with lighter brown underparts, sometimes with a darker cap and streaking on the throat. Juveniles resemble females but are often paler and more streaky.

2. 2

   Beak shape

   Shape and color of the bill: a key field mark.

   Long, stout, conical, and sharply pointed; black in color.

3. 3

   Eye color

   Iris color and any distinctive eye markings.

   Bright yellow (adults), dark brown (juveniles)

4. 4

   Leg color

   Leg and foot color.

   Black

5. 5

   Distinguishing features

   Standout features that separate this species.

   Males possess an exceptionally long, keel-shaped tail, often longer than their body. Females have a noticeably shorter tail. Both sexes have striking yellow eyes.

6. 6

   Juvenile appearance

   How young birds differ from adults.

   Juveniles are similar to adult females but are generally paler brown, often with more noticeable streaking on the breast and throat. Their eyes are dark brown, gradually changing to yellow as they mature.

7. 7

   Seasonal changes

   Plumage variation between breeding and non-breeding seasons.

   No significant seasonal plumage changes. Plumage remains consistent year-round, though wear and tear can make iridescence appear less vibrant over time.

8. 8

   Sexual dimorphism

   How males and females differ.

   Pronounced sexual dimorphism. Males are significantly larger (up to 50% heavier) and have a much longer, iridescent black tail and body. Females are smaller, duller brown, and have a shorter, less prominent tail.

Key field marks

• Size and Shape. Look for a large, slender black bird with a very long tail, especially in males. The tail is often held in a distinctive V-shape during flight.
• Plumage Color. Males are iridescent black, appearing purple, blue, or green in good light. Females are dark brown with a paler breast and a shorter tail.
• Eye Color. Adults have striking bright yellow eyes, a key field mark.
• Vocalizations. Listen for their distinctive, often harsh and varied calls, including raspy notes, whistles, and gurgles. They are very noisy birds.
• Behavior. Observe their confident, often bold behavior, foraging on the ground, and their tendency to gather in large, noisy flocks, especially at roosts.

Explore the Great-tailed Grackle