Much work has been conducted to examine the predator–prey relationship
between A. rubens and M. edulis in relation to body size but we
adopted a novel approach to examine how emersion stress may alter
these relationships. Further to this we examined how barnacle fouling,
which is of particular interest to the mussel cultivation industry, may alter these predator–prey relationships. Emersion stress had no effect
on the feeding rate of A. rubens and the relative size of prey was
shown to be more important in determining predation rates. A more
complex result emerged for starfish feeding on fouled and unfouled
prey. Barnacle fouling had a negative effect on the feeding rate of medium
starfish preying on large mussels and a similar trend was seen for
large starfish preying on small mussels. For all other predator–prey
combinations, however, fouling had no effect on predation rates.