Anemones Fight Back Against Their Opressors

From van der Meij and Reijnen (2011) Fig. 1 a–e The unsuccessful attempt of an edwardsiid sea anemone to feed on a Nembrotha lineolata. f A non-responsive Phyllidia ocellata caught by the tentacles of an edwardsiid sea anemone

You may not realize that those unassuming slugs of the oceans, nudibranchs, are voracious predators in hiding.  Sponges, corals, hydroids, bryozoans, anemones, barnacles, the Portugese Man-O-War, and even other sea slugs will wind up in the digestive tract of a nudibranch.  Not even other nudibranchs, even if they are same species, can escape the eating fury of the nudibranch.  But one species is fighting back.

Crustaceans and fish feed on the nudibranch, but rarely does the nudibranch’s prey become its predator.  Off Malaysia, sea anemones are doing it for themselves.  Photos (above) were taken of the a reef-dwelling anemone, belonging to a species of the family Edwardsiidae, attempting to feed on a nudibranch of the species Nembrotha lineolata. The anemone was observed to have the nudibranch partially swallowed. This was before the slug was able to stretch itself to the surrounding sand and pull itself free. In another case, an anemone had a paralyzed or dead nudibranch in its tentacles.  The anemone was actively moving its tentacles in attempt to move the prey into its “mouth”.

We at DSN support anemones in their struggle against Molluskan domination. In honor of anemones, we dedicate the two following songs of rising above to you.

Meij, S., & Reijnen, B. (2011). First observations of attempted nudibranch predation by sea anemones Marine Biodiversity DOI: 10.1007/s12526-011-0097-9

Dr. M (1720 Posts)

Craig McClain is the Assistant Director of Science for the National Evolutionary Synthesis Center, created to facilitate research to address fundamental questions in evolutionary science. He has conducted deep-sea research for 11 years and published over 40 papers in the area. He has participated in dozens of expeditions taking him to the Antarctic and the most remote regions of the Pacific and Atlantic. Craig’s research focuses mainly on marine systems and particularly the biology of body size, biodiversity, and energy flow. He focuses often on deep-sea systems as a natural test of the consequences of energy limitation on biological systems. He is the author and chief editor of Deep-Sea News, a popular deep-sea themed blog, rated the number one ocean blog on the web and winner of numerous awards. Craig’s popular writing has been featured in Cosmos, Science Illustrated, American Scientist, Wired, Mental Floss, and the Open Lab: The Best Science Writing on the Web.