Brown Skua vs South Polar Skua

In short

Brown Skua and South Polar Skua are both large, aggressive seabirds with similar diets and behaviors, making them challenging to differentiate. The most reliable field mark is the plumage tone: South Polar Skua exhibits colder, darker tones without rufous, while Brown Skua often shows warmer brown tones. Both species have a white 'skua flash' on the wings, but South Polar Skua adults typically have a buffy yellow nape.

Identification tips

1. Look for the overall plumage tone: Brown Skua is warmer, South Polar Skua is colder. 2. Check for a buffy yellow nape in adult South Polar Skuas. 3. Consider the location: Brown Skua is more likely in subantarctic regions, South Polar Skua in Antarctic or northern waters outside breeding season.

Size

Both species are similar in size, robust and powerful, typical of large skuas.

Plumage

Brown Skua generally has warmer brown tones, while South Polar Skua's dark morph is colder and lacks rufous. South Polar Skua adults have a buffy yellow nape, absent in juveniles and Brown Skua.

Behaviour

Both species are aggressive and opportunistic feeders, known for piratic behavior and a diet that includes fish, carrion, and other birds.

Habitat

Brown Skua is typically found in subantarctic regions, while South Polar Skua breeds in Antarctica and migrates to northern waters.