What extinct cormorant from the Bering Sea was flightless and last seen in 1850?

The flightless cormorant from the Bering Sea that disappeared around 1850 was the Spectacled cormorant, also called Pallas's cormorant.

Its scientific name is Urile perspicillatus, although older sources use Phalacrocorax perspicillatus. It lived mainly on Bering Island and possibly elsewhere in the Commander Islands and nearby Kamchatka. At up to about 100 centimeters long and several kilograms in weight, it was the largest known cormorant.

Explorer Georg Wilhelm Steller first described it during Vitus Bering's 1741 expedition. Steller noted that the bird was enormous, clumsy, and almost flightless; anatomical evidence later supported the view that it had greatly reduced flying ability.

The population collapsed after whalers, fur traders, and settlers arrived, with hunting for food and feathers a major pressure. The last birds were reported around 1850 on Ariy Rock, a small islet near Bering Island. Pleistocene fossils found in Japan show that its ancient range was once much wider.