Marine Life
Crustaceans
From tiny skeleton shrimp to large spiny lobsters, crustaceans inhabit almost every part of southern Australia’s temperate marine environment. Explore their extraordinary forms, behaviours and life cycles across the Great Southern Reef.
Ecology and Diversity
Crustaceans of Southern Australia
Crustaceans are among the Great Southern Reef’s most varied inhabitants, from minute amphipods clinging to seagrass to crabs and large lobsters moving through rocky reef and kelp habitats.
Protected by a hard exoskeleton and equipped with jointed limbs, they occupy rocky reefs, seagrass meadows and sandy inshore waters. Many act as grazers, scavengers or predators, while moulting allows them to grow and transform throughout their lives.
Crustaceans of the Great Southern Reef
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Blue swimmer crabs (Portunus armatus)
A fast-moving swimming crab commonly encountered in seagrass meadows and shallow sandy waters around the Great Southern Reef.
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Golden Decorator Crab (Naxia aurita)
A spider crab that fastens pieces of seaweed and other living material to its shell, creating remarkably effective camouflage.
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Skeleton Shrimp (Family Caprellidae)
Tiny, slender amphipods whose hair-like bodies help them disappear among fine seaweeds, hydroids and other marine growth.
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Southern Rock Lobster (Jasus edwardsii)
A large spiny lobster native to southern Australia and New Zealand, usually sheltering in kelp-covered reef crevices during the day.
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Spider crab (Leptomithrax gaimardii)
An iconic southern crab known for forming dense seasonal aggregations, where safety in numbers helps protect animals while they moult.
Explore more Marine Life
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Cephalopods
Learn about southern Australia’s octopuses, squid and cuttlefish.
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Invertibrates
Discover the many invertebrate groups that contribute to reef biodiversity.
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Seaweeds
More than 1,500 seaweed species occur across the Great Southern Reef, including the kelps that create its underwater forests.
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Fish
From tiny reef fish to iconic seadragons and large pelagic species, the Great Southern Reef supports remarkable fish diversity.
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