Tide Pool Bully

What has five arms, wears leather, and is deadly (to sea anemones)?



When we first got our leather star (Dermasterias imbricate) we were impressed by its textured good looks and willingness to slide up into the handling area for inquiring hands to touch it. Although these echinoderms are known to eat sea anemones, we hoped that with ample food, it might suppress its predatory urges. But over time, a series of mysterious casualties were taking place in the tide pool. Sea anemones were disappearing or becoming damaged, with no evidence of human mishandling. Whatever other circumstances, the leather star was always lurking near the scene of the devastation. Animal Caretaker Cari Garand was able to put together the clues, and recommended we deal swiftly with the rogue sea star.


But now we ran into a problem. Pacific Science Center’s tide pool touch tank is considered a terminal facility. This means the department of Fish and Wildlife had determined that our animals couldn’t be returned to the sea. Because we feed our tide pool seafood from other regions, our animals could harbor shellfish virus or other pathogens, harmless to humans but that would make them more of a menace to beach wildlife than our leather star already was to our anemones.


Without the option of release in the wild, a tough decision lay before us. We could let the leather star go on destroying our anemone population, or we could destroy the leather star. Or was there a third way? While we worked out a plan, we removed the star from the exhibit area and isolated it in our filtration vat. Here, it could be fed and looked after without having access to our exhibit animals. Cari contacted Tim Carpenter, at Seattle Aquarium. He graciously agreed to accept the star, and provide a habitat where it would fit in better. All the paperwork was arranged, and on Oct. 25, Tim's assistant, Katie, completed the transfer.


The star had outgrown our little tide pool. We hope he finds it is better to be a small “fish” in a bigger pond.