Sea balls (also known as Aegagropila or Pillae marinae) are tightly packed balls of fibrous marine material, recorded from the seashore. They vary in size but are generally up to 7 centimetres (2.8 in) in size. In Edgartown, Massachusetts a longish sea ball around 45 centimetres (18 in) in diameter has been found.^{[ citation needed]} Others have been reported at Dingle Bay in Ireland ^[1] and at Valencia, Spain. They may occur in hundreds and are composed of plant material, in majority seagrass rhizome netting torn out by water movement.^{[ citation needed]}

In recent years they have been shown to contain more and more plastic marine debris and even microplastics. ^[2]

Gallery

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  A small sea ball
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  A sea ball pulled apart, with a 1 euro coin for scale
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  Sea balls occasionally drift ashore en masse, seen here on a beach in Sanary-sur-Mer, France
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  Sea balls in a historic collection

References