Researchers' Diaries

Alison Sampey

Research Officer, Department Aquatic Zoology, Western Australian Museum

Echinoderms (sea stars, sea urchins, sea cucumbers, feather stars and brittle stars)

Searching for echinoderms (sea stars, sea cucumbers, brittle stars, feather stars and sea urchins) on Adele Island and Montgomery Reef is hard work as they are hidden in the most inaccessible places. However, the scenery was spectacular and the waters very warm (around 27ºC) making ping a comfortable experience. And, of course, it was fantastic to have the chance to see and work in this part of the country where whales, dolphins, sharks and crocodiles abound - but I didn't find many echinoderms! Only a few species are found living out in the open, while most echinoderms prefer to be found under rocks and within the reef matrix, or associated with other animals, such as sponges and corals. You need to search very hard to find them. For the most part, I found there were very few turnable rocks for these amazing animals to hide under. The large tidal flow probably washed away any loose rubble large enough to provide shelter, so there was a lack of suitable habitat or at least habitat easy and practical for me to sample.

Despite this, I did collect species from all 5 major groups of echinoderms, sea stars (3 species), sea urchins (about 4 species), brittle stars (more than 15 species), feather stars (about 5 species) and sea cucumbers (around 12 species). Some of these are turning out to be quite interesting. Two brittle stars, Ophiarthrun elegans and Ophiomastix mixta, were unusually abundant. Unexpectedly, there was no Ophiocoma spp. at all. Identifications are still ongoing so we will most likely have more species than listed above. Generally, there were fewer species of echinoderms compared to the reefs of the offshore atolls such as the Rowley Shoals (see the “Publications” page of this website).

Cushion Seastar, Culcita schmideliana, Montgomery Reef

Photo: Alison Sampey

Copyright Western Australian Museum.

Pinkfish (Sea cucumber), Holothuria (Halodeima) edulis. Montgomery Reef

Photo: Alison Sampey

Copyright Western Australian Museum.

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