Seals and sea lions are marine mammals known as pinnipeds; there are 33 species worldwide. All are carnivores that hunt at sea – often for fish and squid – and breed on land, mostly in large, noisy colonies.

A sea lion pup and mum snuggle up on the Eyre Peninsula, South Australia. Pups are born with a chocolate-brown coat that moults after about five months.

The Australian sea lion and Australian and New Zealand fur seals are the only species that breed on and around Australia’s mainland and near-shore islands.

Ausralian sea lions and NZ fur seals, along with Antarctic and sub-Antarctic fur seals – which breed on Australian sub-Antarctic islands – belong to the ‘eared’ pinniped family: all have small outwardly visible ears.

Energetic creatures, these sea lions are contributing to the recently developed national Integrated Marine Observing System (IMOS), which employs oceanographic instrumentation on ships, moorings and buoys to map and monitor the marine environment right around Australia.

Australian sea lions, (Neophoca cinerea), are found from the Houtman Abrolhos islands off WA’s south-west coast to the Pages Islands in south-eastern SA.

Before commercial sealing, Australian sea lions were found right along Australia’s southern coastline but it is now restricted to the offshore islands of WA and SA.

The more chocolate-brown males can weigh up to 300kg. 

Female sea lions return to breed at the colonies where they were born, are a silver-ash colour and reach about 80kg in weight. 

Being mammals, sea lions are of course air-breathers. But they have a remarkable ability to hold their breath and have been recorded diving to depths of almost 300m, while remaining submerged for about seven minutes.

Female sea lions return to breed at the colonies where they were born, are a silver-ash colour and reach about 80kg in weight. 

Sea lions, like all pinnipeds, are carnivores.

Australian sea lions are often playful and zoom around in the water.

Australian sea lions have the longest weaning period of any pinniped species. Pups remain with mums for 18 months.

As a top predator, the Australian sea lion is also a sentinel of climate change, with the species’ diet and population trends reflecting broader shifts in marine food webs and productivity

Swim and snorkel with sea lions at Seal Cove on this island, just a short boat ride from Port Lincoln, SA. The Hopkins colony has become used to human visitors on guided tours.

Sea lions can dive as deep as 300m below sea level. They keep air in their upper airways as a reservoir when they’re diving.

Poin Labatt Conservation Park, South Australia.

The sea lion colony at Poin Labatt Conservation Park, South Australia.

Unlike New Zealand fur seals, which also occur in these waters, Australian sea lions are benthic feeders; they forage on the sea floor. This one is collecting a crab.

Sea lion poo contains a high level of bacteria that can metabolise iron and phosporous, important nutriets for phytoplankton, itself a fundamental food for many marine species.