About Leucocarbo atriceps bransfieldensis (Murphy, 1936)
The imperial shag Leucocarbo atriceps bransfieldensis measures 70–79 cm (28–31 in) in total length and weighs 1.8–3.5 kg (4.0–7.7 lb), and males are typically larger than females. Most of its body is covered in glossy black feathers, with a white belly and neck. It has a distinctive ring of blue skin surrounding its eyes, an orange-yellow nasal knob, pinkish legs and feet, and an erectile black crest. In the non-breeding season, adult imperial shags lose their crest, have duller-colored facial skin, and have less or no white coloring on their back and wings. Their bill is serrated, an adaptation used for catching fish. Different related taxa vary mainly in how much white coloring appears on the cheeks, ear-coverts, wing-coverts and back. While most taxa have white cheeks and ear-coverts, these areas are black in the taxa albiventer, purpurascens and melanogenis. Chicks are a uniform brownish color. Immature birds are brownish and white (rather than black and white like adults), have dull facial skin, and lack the orange-yellow nasal knob and blue eye-ring.
