Imagine unlocking the ocean’s mysteries through the eyes of a sea lion—that’s exactly what South Australian aquatic scientist Nathan Angelakis is doing.
Angelakis and his team equipped eight sea lions with cameras and GPS trackers to explore the deep waters beyond human reach.
The sensors were attached using neoprene patches glued to the backs of eight adult female. The equipment was designed to be small and non-cumbersome, weighing less than 1 per cent of the sea lions’ body weight, so as not to hinder the animals or affect their behaviour.
On completion of the project the sensors were removed with the patches without damaging the sea lions’ fur.
“The sea lions provide a good way of mapping the ocean across large, and particularly remote, deep, offshore areas that we just can’t access by other means,” said Angelakis.
The doctoral candidate and his team at the South Australian Research and Development Institute (Aquatic Sciences) and University of Adelaide glued lightweight cameras to the sea lions’ fur to identify and map seabed habitats across South Australian waters.
The extraordinary footage has revealed previously unmapped sea lion habitats, new reefs, and diverse seafloor environments.
The sea lion helpers have saved the scientists time and money and provided an insight that would have been impossible for humans. Angelakis says “to conduct this sort of work” usually requires major resources such as specialised boats, costly equipment, and relies on the vagaries of weather.
Sea puppies named after Greek gods
The researchers from the University of Adelaide turned to eight adult female Australian sea lions for help. The scientific name for these Australian sea puppies is Neophoca cinerea, and the ones who helped Angelakis, come from different colonies .
Daphne, Phoebe, Iris, and Pasithea became the sea lion “camera crew” in the study.
The sea lions’ names were chosen by members of the tourism operation at Seal Bay, one of the colonies.
“They’ve got a set of cards, or a book, or something that they use, it’s a nice thing for them to do, and they also come out and help us in the field and get to be a part of the research,” says Angelakis.
The 29-year-old marine biologist said the female sea lions are “really important” for population viability and offer “more reliability in retrieving our instruments” since they return to nurse their pups within a few days.
A family bond with the ocean
Angelakis’s passion for the ocean runs deep – he is a member of the well-known Adelaide based, Angelakis family.
His grandfather, and great-grandfather were sponge divers and fishermen in Greece.
The Angelakis Bros. are major fishmongers founded in 1960. The family has, over five decades, established seafood outlets in the Adelaide Central Market, Golden Grove, Glenunga and Burnside Village.
“I’ve always had a connection to the ocean, I grew up snorkelling and surfing, I just became obsessed with the ocean and marine life.
“It led me to wanting to learn more about the sea, and most importantly, protect it,” says the marine scientist.
Angelakis is currently in Poseidon’s home, Greece, mapping his own family’s past. He will visit his grandfather’s island-home Symi, the Dodecanese island is known traditionally for shipbuilding and sponge industries. Syme, is named from Syme the nymph, the daughter of Ialysos and Dotis, the kidnaped bride of the sea god Glaucus.
He will follow his papou’s footsteps from family home to primary school, then Angelakis heads to the island of Rhodes the largest of Greece’s Dodecanese islands and his yiayia’s birthplace.
The findings
Much is already known about the Australian sea lions’ diving behaviours and movement patterns, however Angelakis notes a gap in knowledge about their habitats, foraging behaviours, and prey targets.
“Because the species is endangered and their populations have declined by over 60 per cent over the last 40 years, identifying key resources is really key to effectively managing and conserving their populations in the future.”
The study revealed that sea lions use different types of habitats along the southern coastline which include sponge reefs and gardens, sand plains, and kelp reefs.
“By combining all that information with the environmental and oceanographic data, we were able to get some idea about how different factors might drive or change these habitats,” said Angelakis.
“That sort of information is important,” in predicting the “impact of human activity on marine environments around the world.”
Findings, all derived from the deft work of the sea lions’ camera work, were published in the journal Frontiers in Marine Science – and here is some of the never seen before footage of a sea lions’ POV.
A commitment to ocean conservation
The Adelaide-born Angelakis completed a Bachelor of Marine Biology at Flinders University in South Australia, then went on to earn an honours degree and a PhD, in collaboration with SARDI.
After volunteering and working on various marine projects, his supervisor from SARDI, proposed a PhD idea that eventually led to the sea lion study.
As for the future, Angelakis’s goals “are quite simple.”
“If I can conserve any little part of the ocean or help any species from becoming endangered or extinct, that would be a fulfilling career for me. For me, it’s about conservation—keeping the oceans healthy and protecting the species we have. That’s my main drive.”
Angelakis’s research, with the help of his sea lion camera crew, may help underwrite a healthier, more sustainable future for our oceans and the diverse life they support.
