The Ross Sea hosts an amazing diversity of marine animals, including at least 10 mammal species, half a dozen species of birds, 95 species of fish, and in excess of 1,000 invertebrate species. We've listed facts about some of the key Ross Sea species below.
Adélie penguin(Pygoscelis adeliae)
Ross Sea population: 3 million
Size: Up to 76 cm tall
Diet: Small fish and krill
Predator: Skuas, Leopard seals
Did you know: Adélie penguins are the smallest Ross Sea penguin, but the most abundant. Their colony at Cape Royds in the Ross Sea is the southernmost penguin colony in the world.
Emperor penguin(Aptenodytes forsteri)
Ross Sea population: 240,000
Size: Up to 1.2 m tall and up to 45 kg
Diet: Fish, squid and crustaceans
Predators: Leopard seals, orcas
Did you know: Emperor penguins are the largest penguin species and are the only species that breeds during the brutal Antarctic winter. Their amazing life cycle, in which they trek over 50-120 km of ice to reach their breeding colonies, was featured in the French documentary, March of the Penguins and the award winning animation Happy Feet.
Antarctic petrel (Thalassoica antarctica)
Ross Sea population: 5.5 million
Wingspan: Up to110 cm
Diet: Krill, fish, and small squid
Predators: None known
Did you know: The Antarctic Petrel is the only known species in the genus Thalassoica. In the spring they head inland and nest on mountaintops hundreds of kilometres inland, while in late winter, they're occasionally seen off the coast of New Zealand and Australia.
Snow petrel (Pagodroma nivea)
Ross Sea population: One million
Wingspan: Up to 95 cm
Diet: Krill, fish and squid
Predators: None known
Did you know: Snow Petrels are stark white, blending in well with the snow and ice. Some consider them the most beautiful birds in Antarctica. Like the Antarctic Petrel, Snow Petrels also nest on inland mountaintops.
South polar skua(Stercorarius maccormicki)
Ross Sea population: 19,000
Wingspan: Up to 160 cm
Diet: Fish, chicks, eggs, squid, krill and carrion
Predators: None known
Did you know: South polar skuas are fierce predators, often stealing fish from other birds and actively preying on penguin chicks and eggs. The largest South Polar Skua colony in the world is found at Cape Crozier in the Ross Sea
Antarctic minke whale (Balaenoptera bonaerensis)
Ross Sea population: 21,000
Size: Up to almost 11 m in length and ten tons in weight
Diet: Krill and fish
Predator: Orcas
Did you know: Minke whales are the smallest baleen whales in the world. Antarctic minke whales are their own separate species, but they are closely related to common minke whales
Killer whales Ecotype A, B & C (Orcinus orca)
Three distinct killer whales types live in the Ross Sea, but ecotype C is by far the most common.
Ross Sea population: At least 3,400, but mostly ecotype C
Size: Ecotype A is the largest, growing up to 9 m, while ecotype C have an average length of 5.6 m
Diet: Ecotype A feeds mainly on Antarctic minke whales, while ecotype B primarily feeds on seals and emperor penguins, and ecotype C feeds almost exclusively on fish, particularly the Antarctic toothfish
Predator: None known
Did you know: Killer whale ecotype A lives mainly in continental slope ice-free water, while ecotype B mainly occupies inshore waters, and ecotype C lives in the pack-ice of continental shelf waters.
Weddell seal (Leptonychotes weddellii)
Ross Sea population: 30,000 to 50,000
Size: Up to 3.3 m in length and 600 kg in weight
Diet: Mostly fish and squid
Predator: Orcas, Leopard seals
Did you know: Weddell seals have the most southerly distribution of any mammal, living as far south as McMurdo Sound.
Crabeater seal (Lobodon carcinophagus)
Ross Sea population: 204,000
Size: 2.5 m in length and 400 kg in weight
Diet: Mostly krill
Predators: Leopard seals
Did you know: Crabeater seals earned their name from their specially adapted teeth, which have extra projections so that when they gulp in seawater they can strain out the krill
Leopard seal (Hydrurga leptonyx)
Ross Sea population: 8,000
Size: Up to 3.5 m in length and 460 kg in weight
Diet: Penguins, smaller seals, fish and squid.
Predators: None known, but perhaps orcas
Did you know: The leopard seal is named for its black-spotted coat. Like their feline namesake, leopard seals are ruthless predators. Check out this National Geographic slideshow of leopard seals, featuring the infamous "death shake," in which a leopard seal can rip a penguin from it's skin within seconds
Antarctic toothfish (Dissostichus mawsoni)
Ross Sea population: Unknown
Size: More than 2 m in length and in excess of 150 kg in weight
Diet: Fish and squid
Predators: Sperm whales, ecotype C killer whales, Weddell seals, and colossal squid
Did you know: The Antarctic toothfish is famous for producing antifreeze glycoproteins that allows it to survive in the ice-laden waters of the Southern Ocean.
Antarctic silverfish (Pleuragramma antarcticum)
Ross Sea population: Unknown
Size: Up to 25 cm
Diet: Krill
Predators: Penguins, seals, toothfish, whales, and other seabirds
Did you know: Like the Antarctic toothfish, this much smaller fish also produces antifreeze proteins. The Antarctic silverfish is regarded as the only truly pelagic fish in Antarctic waters
Antarctic krill(Euphausia superba)
Ross Sea population: Estimated 500 million tones in the Southern Ocean.
Size: Adult Antarctic krill are approximately six centimetres in length and weigh over a gram.
Diet: Mainly herbivorous, feeding on the phytoplankton (microscopic suspended plants) and occasionally planktonic animals (zooplankton).
Predators: Most of the larger Antarctic animals, the seals, whales, seabirds, fish and squid, depend directly or indirectly on Antarctic krill.
Did you know: Antarctic krill can survive for long periods (up to 200 days) without food and can shrink in length as they starve.
Crystal krill(Euphausia crystallorophias)
Ross Sea population: Unknown
Size: smaller than Antarctic krill, reaching a maximum length of 3.4cm. Females are slightly larger than males.
Diet: Phytoplankton, sometimes algae scraped from under the ice.
Predators: an important food source for coastal predators, eaten by whales and other large animals (Minke whales, Weddell seals, Adelie penguins, silverfish).
Did you know: This species is found from the surface down to usually
300 to 650 meters depth but has been recorded near 4,000 meters.
