Which penguin species is the deepest-diving bird, reaching depths beyond 500 metres?

The emperor penguin is the deepest-diving bird, reaching depths beyond 500 metres.

Emperor penguins dive beneath Antarctic sea ice to pursue fish, squid and crustaceans. Their compact bodies, dense bones and oxygen-management adaptations help them withstand pressure and remain underwater for extended periods. Individual dives can last more than 20 minutes in exceptional records.

The species breeds during the Antarctic winter, when temperatures and winds are severe. After the female lays a single egg, the male balances it on his feet and covers it with a warm brood pouch while she returns to sea to feed.

King penguins are similar in appearance but generally dive less deeply. Emperor penguins are also the heaviest living penguins, while their breeding cycle is one of the most demanding among birds.