Survival of larval Strongylocentrotus purpuratus under ocean warming and food availability scenarios

We tested how thermal tolerance itself can be fundamentally altered by food limitation hypothesis by quantifying how temperature and food concentrations interact synergistically to shape survival throughout larval development of purple urchins (Strongylocentrotus purpuratus). Larval sampling was conducted every two days to estimate changes in larval density and competency, in conjunction with water changes and feedings. Larval densities were quantified by concentrating larval cultures to 100 mL and counting the number of larvae found in five 1 mL subsamples. Density counts continued until larvae showed signs of metamorphosis, as determined by the presence of a rudiment and exposed tube feet.