Species Information

Red alga (Grateloupia turuturu) Red alga (Grateloupia turuturu)
Courtnay Hermann
Red alga (Grateloupia turuturu)
Courtnay Hermann
Red alga
Grateloupia turuturu

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History
  • First found on eastern North American shores in 1996 in Narragansett Bay
  • Northward spread into Gulf of Maine apparently limited by intolerance of very cold water

Characteristics
  • Thin, pink to maroon blades, often with bladelets (pinnae) at base, and a distinctly gelatinous, slippery texture
  • Variable growth forms (divided or undivided, varying blade shapes)
  • Grows singly, but more typically in clumps of up to 8 individuals
  • Grows to full lengths in late summer and early fall, then reduces to crust-like form for overwintering
  • Can grow up to 9 ft (3 m)

Habitat
  • Shallow water to depths of 6.5 ft (2 m), attached to firm surfaces
  • Prefers protected waters such as tidal pools
  • Believed to be unable to survive very cold water

Known Distribution in the Northeast
  • Boston Harbor to Long Island Sound
  • Native to the Pacific Ocean, possibly Japan

Impacts
  • Growth pattern and habitat preferences make it a threat to native red algal species, particularly Palmaria palmata and Chondrus crispus
  • Broad blades may shade other algae, preventing their growth

Red alga (Grateloupia turuturu)
A. Pappal
Red alga (Grateloupia turuturu)
A. Pappal
Red alga (Grateloupia turuturu)
A. Pappal