These reports note parenthetically that susceptibility to disturbance by anchor ice apparently varies among species: at McMurdo Sound, sponges are disturbed most, whereas abundances of some other sessile epibenthic organisms (anemones, alcyonarians, actinians, stoloniferans, and ascideans) seem unaffected by the presence of anchor ice (Dayton, 1989; Gutt, 2001).