Justin was busy documenting an artificial reef experiment when the army of crabs appeared, with an octopus acting ‘like an excited child in a candy store’, as it chose its final catch. The irony of this unexpected encounter isn’t lost on Justin: ‘An aggregation of crabs the size of a football field wandered through the experiment and we had no idea why.’
Moments like these reinforce how little we know about Australia’s temperate reefs, and ocean ecosystems generally. Spider crabs usually come together for protection while they moult or mate, but these groupings were previously unknown in this area. Crabs like these are common prey for the Maori octopus – the largest in Australian waters.
Nikon D810; 15mm f2.8 lens; 1/100 sec at f14; ISO 400; Nauticam housing; two Ikelite DS161 strobes.
Mercury Passage, Tasmania, Australia
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Justin Gilligan, Australia
Justin works as a freelance photojournalist for a range of nature and travel magazines. He has worked on numerous projects within Australia's Commonwealth and state fisheries and has been contracted to conduct field research in some of the country's most spectacular marine environments. More recently his photojournalism efforts have focused on Australia's temperate reef systems.