How to identify the Indian Grey Hornbill

To correctly identify the Indian Grey Hornbill (Ocyceros birostris), 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

45-61 cm

Wingspan

60-80 cm

Weight

200-400 g

Physical features to check

1. 1

   Plumage

   Overall feather coloration and pattern.

   Overall dull grey plumage, paler on the underparts. The flight feathers are darker, almost blackish, with white tips on the outer primaries. The tail is long and graduated, dark grey with white tips on all but the central feathers.

2. 2

   Beak shape

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

   Large, heavy, and curved blackish bill with a prominent, low, and ridged casque on the culmen. The casque is more developed in males.

3. 3

   Eye color

   Iris color and any distinctive eye markings.

   Dark brown, often appearing black.

4. 4

   Leg color

   Leg and foot color.

   Dark grey to blackish.

5. 5

   Distinguishing features

   Standout features that separate this species.

   The most distinctive features are its large, curved bill with a relatively small, ridged casque, and its overall grey coloration. The white tips on the tail feathers are also a good field mark.

6. 6

   Juvenile appearance

   How young birds differ from adults.

   Juveniles have a smaller, undeveloped casque and a shorter, paler bill. Their plumage is similar to adults but may appear slightly duller.

7. 7

   Seasonal changes

   Plumage variation between breeding and non-breeding seasons.

   No significant seasonal plumage changes.

8. 8

   Sexual dimorphism

   How males and females differ.

   Males have a larger, more prominent casque on the bill, which is typically darker. The lower mandible of the male's bill is often darker. Females have a smaller, less developed casque and a paler, often yellowish-tinged lower mandible. Juveniles resemble females but have a smaller, undeveloped casque and a shorter bill.

Key field marks

• Size and Shape. Look for a medium-sized, slender hornbill with a long tail and a disproportionately large, curved bill.
• Plumage Color. Observe the overall dull grey body plumage, paler on the underparts.
• Bill and Casque. Note the blackish bill with a low, ridged casque. Males have a larger casque than females.
• Tail. Identify the long, dark grey tail with prominent white tips on the outer feathers.
• Flight. Watch for its characteristic undulating flight pattern with heavy, noisy wing beats.
• Vocalizations. Listen for its distinctive loud, cackling, laughing calls.

Explore the Indian Grey Hornbill