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Licensed Unlicensed Requires Authentication Published by De Gruyter September 22, 2015

The unusual occurrence of green algal balls of Chaetomorpha linum on a beach in Sydney, Australia

Julia Cooke ORCID logo, Robert Lanfear, Alison Downing, Michael R. Gillings, Alistair G.B. Poore, Ian D. Goodwin, Liette S. Waldron, Aaron Phillips, Yola Metti and Matthew W. Bulbert
From the journal Botanica Marina


In spring 2014, thousands of green algal balls were washed up at Dee Why Beach, Sydney, New South Wales, Australia. Reports of algal balls are uncommon in marine systems, and mass strandings on beaches are even more rare, sparking both public and scientific interest. We identified the algal masses as Chaetomorpha linum by using light microscopy and DNA sequencing. We characterize the size and composition of the balls from Dee Why Beach and compare them to previous records of marine algal balls. We describe the environmental conditions that could explain their appearance, given the ecophysiology of C. linum.

Corresponding author: Julia Cooke, Department of Environment, Earth and Ecosystems, The Open University, Milton Keynes, MK7 6AA, UK, e-mail: ; and Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia.


We thank Dr Nick Yee for assisting in identification of the non-dominant algae and Thomas Mortlock for generating the wave figure.


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Received: 2015-7-28
Accepted: 2015-9-3
Published Online: 2015-9-22
Published in Print: 2015-10-1

©2015 by De Gruyter

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