The Ross seal breeds in dense Antarctic pack ice. Six seals tracked off Queen Maud Land moved into open water after their February moult and returned to the pack ice in October.
Its back ranges from dark to light brown, while the belly is silvery white. It has large eyes and needle-like teeth for catching prey.
Ten adults were tagged off Queen Maud Land in February 2001 after moulting; six provided location and dive records for about a year. Those six moved about 2,000 km north and remained in open water south of the Antarctic Polar Front before returning south to the pack ice in October. The records showed about 100 dives per day, mostly 100–300 m deep, with a deepest recorded dive of 792 m. From the dive patterns, the authors inferred feeding consistent with mid-water fish, squid, and some krill under pack ice, and myctophid fish and squid in open water. Haul-out records for three females indicated a median nursing period of 13 days in mid-November.
An extinction-risk assessment has not been added yet.