Swinhoe's Storm-Petrel vs Matsudaira's Storm-Petrel

In short

Swinhoe's Storm-Petrel and Matsudaira's Storm-Petrel are both dark storm-petrels, but Matsudaira's is larger and has a distinctively longer tail. In flight, Matsudaira's shows a more languid wingbeat compared to the quicker, more fluttery flight of Swinhoe's.

Identification tips

1. Size and structure: Matsudaira's is larger with a longer tail. 2. Flight style: Matsudaira's has a slower, more languid flight. 3. Plumage: Look for a slightly paler rump on Matsudaira's, though this can be unreliable. 4. Location and season: Consider the geographical range and time of year, as both species have overlapping ranges but may vary seasonally.

Size

Matsudaira's Storm-Petrel is noticeably larger than Swinhoe's Storm-Petrel.

Plumage

Both species are predominantly dark, but Matsudaira's may show a slightly paler rump, though this is not always reliable.

Behaviour

Matsudaira's Storm-Petrel has a slower, more languid flight with deeper wingbeats compared to the quicker, more fluttery flight of Swinhoe's Storm-Petrel.

Habitat

Both species are pelagic and are typically found far from land, often in similar oceanic regions.

Voice

Vocalizations are rarely heard at sea, and there is little information on differences in calls between these two species.