These orange sea pen leaves (Ptilosarcus gurneyi) look interesting and provide an open support structure for the feeding polyps. Each sea pen is a colony of specialized polyps (small anemone-like individuals) working together, and one polyp even develops into a tall rigid central stock that supports the other polyps and provides an anchor to the ocean floor. This colony has the ability to expel water and contract down into the seafloor when disturbed, and then take water back in expanding to its original shape after the threat has passed. The orange sea pen anchors itself into muddy or sandy substrates and grows to around 19 inches (48 cm) tall, with a range from northern Alaska to northern Mexico.
References:
Fretwell, Kelly. “Orange Sea Pen, Ptilosarcus gurneyi” Biodiversity of the Central Coast, University of Victoria, 2016, https://www.centralcoastbiodiversity.org/orange-sea-pen-bull-ptilosarcus-gurneyi.html
Lamb, Andy and Hanby, Bernard. Marine Life of the Pacific Northwest: A Photographic Encyclopedia of Invertebrates, Seaweeds and Selected Fishes. Madeira Park: Harbour Publishing, 2005. (An online version of this book is also available to subscribers at https://knowbc.com)
