Australian researchers are working to save local sea lion pups from potentially fatal hookworm infections that threaten to wipe out the animal's dwindling population.
All Australian sea lion pups are infected with hookworms, spread through larvae in their mothers' milk.
The hookworms weaken immune systems and can be fatal.
A research team led by University of Sydney vet Rachael Gray are trialling anti-parasitic drugs on pups that are applied directly to skin, rather than being injected into their blood stream.
The team are monitoring 180 sea lion pups at Seal Bay in South Australia over two breeding seasons.
Half are being treated with the drug while the rest are in a control group.
"We will monitor them for 18 months to see how the treatment not only improves pup health and growth, but also survival to breeding adult as part of a longer-term study," Dr Gray said on Friday.
"Hopefully this eventually aids the species' population recovery."
Australian sea lion numbers have not recovered since humans stopped hunting them.
On the contrary, their numbers are in decline.
The majestic creature has been listed as endangered on the International Union for Conservation of Nature for more than a decade.
But attempts to increase its protection status from vulnerable status are being held up by red tape.