To evaluate the impacts of prior exposure to sub-optimal salinity
on the sediment-clearing response of S. radians, sediment-clearing
trials were conducted following 24 h of exposure to 20 psu (n=16 colonies),
25 psu (n=16 colonies), 35 psu (controls, n=15 colonies), and
45 psu (n=12 colonies). While 15 psu was used as the lowest salinity
treatments in all previous experiments, salinity levels reached 20 psu
during the sediment clearing experiment. All of the colonies used
were hemispherical. A second sediment-clearing trial was performed
24 h and 5 d after the initial experiment to document the recovery of
the sediment clearing response after return to control oceanic salinity
conditions.