Short-tailed Shearwater vs Bryan's Shearwater

In short

The Short-tailed Shearwater and Bryan's Shearwater can be distinguished primarily by their size and plumage. Short-tailed Shearwaters are larger with a more robust build, while Bryan's Shearwaters are smaller and more delicate. Look for differences in plumage coloration and tail length when observing these species in the field.

Identification tips

1. Size: Use the size difference as a primary indicator; Short-tailed is larger. 2. Plumage: Look for the darker, more uniform plumage of the Short-tailed versus the contrasting cap and white underparts of Bryan's. 3. Tail: Short-tailed Shearwaters have a shorter tail compared to the more proportionate tail of Bryan's. 4. Location: Consider the geographic location and habitat, as Bryan's Shearwater is more restricted in range.

Size

Short-tailed Shearwaters are larger and bulkier compared to the smaller, more delicate Bryan's Shearwater.

Plumage

Short-tailed Shearwaters have uniformly dark plumage, often appearing sooty brown, whereas Bryan's Shearwaters have a more contrasting plumage with a dark cap and white underparts.

Behaviour

Both species exhibit similar flight patterns typical of shearwaters, with dynamic gliding and flapping, but specific behavioral differences are not well-documented.

Habitat

Short-tailed Shearwaters are often found in open ocean environments, while Bryan's Shearwaters are less frequently observed and have a more restricted range, often near breeding islands.

Voice

Vocalizations are not well-documented for either species in field conditions, making them unreliable for identification.