How to identify the Greater Ani

To correctly identify the Greater Ani (Crotophaga major), 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

43-51 cm (17-20 in)

Wingspan

Approximately 60-70 cm (24-28 in)

Weight

160-220 g (5.6-7.8 oz)

Physical features to check

1. 1

   Plumage

   Overall feather coloration and pattern.

   Adults are entirely glossy black, often with a bluish or purplish sheen, particularly on the head, neck, and upperparts. The feathers on the head and neck can appear somewhat shaggy or bristly.

2. 2

   Beak shape

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

   Large, heavy, and strongly arched bill, black in color. The culmen (upper ridge of the bill) is noticeably elevated and compressed laterally, giving it a distinctive 'helmet-like' appearance.

3. 3

   Eye color

   Iris color and any distinctive eye markings.

   Dark brown to black

4. 4

   Leg color

   Leg and foot color.

   Black

5. 5

   Distinguishing features

   Standout features that separate this species.

   Its large size, entirely glossy black plumage, and particularly its massive, arched, and laterally compressed bill are the most distinctive features. The long, graduated tail is also characteristic.

6. 6

   Juvenile appearance

   How young birds differ from adults.

   Juveniles resemble adults but may have a duller black plumage with less gloss. Their bill may be slightly less developed and less prominently arched than that of adults.

7. 7

   Seasonal changes

   Plumage variation between breeding and non-breeding seasons.

   No significant seasonal plumage changes. Plumage remains consistent year-round.

8. 8

   Sexual dimorphism

   How males and females differ.

   Males and females are monomorphic in plumage and size, making them difficult to distinguish visually in the field.

Key field marks

• Size and Shape. Look for a large, entirely black bird with a long tail and a distinctive, very large, arched, and laterally compressed bill. It's the largest of the ani species.
• Plumage. Observe the glossy black plumage, which can have a bluish or purplish sheen in good light. The feathers on the head and neck often appear somewhat shaggy.
• Bill. Pay close attention to the bill. The Greater Ani's bill is exceptionally large, deep, and strongly arched, appearing almost helmet-like. This is the key distinguishing feature from other anis.
• Behavior. Watch for its gregarious nature; it's almost always seen in small to large groups. Observe its somewhat clumsy, undulating flight and its habit of foraging on the ground or in low vegetation, often following livestock.
• Vocalizations. Listen for its loud, distinctive 'whee-oo' or 'whee-ooo-ooo' whistles, often given in chorus by the group. These calls are quite different from the calls of other ani species.

Explore the Greater Ani