Jackson Estuarine Laboratory

Chaetomorpha balls foul New Hampshire, USA beaches


Large populations of green balls washed ashore at Plaice Cove on North Beach, Hampton, New Hampshire, USA during June, 2002 and were reported in various local and national newspapers and magazines. The thread-like green alga Chaetomorpha picquotiana made up 79% of the balls’ fresh weight, which averaged 26.6 ± 3.8 g and 5.9 ± 0.3 cm in diameter. Based on photographs, there were about 223 balls m?2 on North Beach on June 12 that had disappeared by early July, 2002. The balls contained 30 species, including 20 seaweeds, 2 flowering plants, and 8 invertebrates. By contrast, quadrat samples (625 cm2) taken on the same beach during late June 2002 included 16 species of seaweeds, of which C. picquotiana was the second most common one, plus 3 species of flowering plants, and 3 species of invertebrates. The enhanced number of invertebrates in the balls compared with those in the quadrats suggests that they serve as a refuge and source of food. Production of the algal balls appears to be based on wave activity, shape and hardness of the nearshore shoreline, light penetration, temperature, and nutrients. Massive entangled mats of drift C. picquotiana (60.3-1453 g fresh wt. m?2) occurred in September 2002 during one of the warmest summers on record in New England.

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Korean Society of Phycology

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