Three species breed around New Zealand’s coastline and on its temperate and subantarctic islands. These are the New Zealand fur seal, the New Zealand or Hooker’s sea lion, and the southern elephant seal. A fourth, the leopard seal, is a frequent visitor. Leopard seals breed in the New Zealand-claimed sector of Antarctica, the Ross Dependency, along with Weddell seals, crabeater seals and Ross seals.
Seals of the savannah
Why are different seal groups named after lions, elephants and leopards? Male sea lions have dense hair around the neck and throat, like a lion’s mane. Male elephant seals have an enlarged curved fleshy snout, resembling an elephant’s trunk. And leopard seals have leopard-like spots as well as the jaws and teeth of a ferocious predator.
Seals played a significant role in the early New Zealand economy. They were an important source of food and skins for Polynesian settlers until depleted on accessible mainland coasts. Later, sealskin and oil were the first products exported to the northern hemisphere, after the first group of European sealers set up camp in remote Dusky Sound in 1792. The quest for seals drove much of the early European exploration of New Zealand’s southern and subantarctic regions. By 1830 the seals were close to extinction. However, enough survived for populations of each species to stage a slow recovery.
Seals evolved from land-based carnivores similar to bears, about 25 to 27 million years ago in the Oligocene period. This was long after the demise of the dinosaurs. All terrestrial vertebrates (land animals with backbones) can trace their beginnings to a moment when some lobe-finned fish walked up the banks of a muddy estuary and the evolution of their lives on land ensued. Yet the sea must have offered attractive pickings for any mammals that could venture back into it. Seals merely followed those that had already pursued such bounty: the whales, dolphins, manatees and dugongs. The earliest known seal fossils are from the eastern North Pacific.