Serpula vermicularis, or Calcareous Tubeworms, are aptly named for the calcium tubes that they build and live in. Two sacs secrete organic material which when combined with calcium creates the curved tubes (1). The tubeworms themselves have a yellow body up to 8 cm in length with a distinctive crown of radioles at the anterior end (1). These feather-like appendages can be red, pink, or orange and have white bands and are used for filter feeding and gas exchange (1). When disturbed, S. vermicularis retreat into their tube, sealing the opening with their operculum. While this behavior does protect S. vermicularis from predation, associated lost-opportunity cost of feeding can be significant and S. vermicularis are known to adjust their hiding behavior with relative abundance of food (2).
(1) Cowles, D. (2006). Serpula columbiana Johnson, 1901. Retrieved November 26, 2017, from https://inverts.wallawalla.edu/Annelida/Serpulidae/Serpula_vermicularis....
(2) Dill, L. M., & Fraser, A. H. (1997). The worm re-turns: hiding behavior of a tube-dwelling marine polychaete, Serpula vermicularis. Behavioral Ecology, 8(2), 186-193. doi:10.1093/beheco/8.2.186
- rocky intertidal