changes in ascent rate, diel behaviour) would lead to differences in PN2 levels and thereby
decompression sickness (DCS) risk between species. Diving lung volume and extent of the dive response
had a large effect on end-dive PN2 . The dive profile had a larger influence on end-dive PN2 than body mass
differences between species. Despite diel changes in dive behaviour, PN2 levels showed no consistent trend.
Model output suggested that all three species live with tissue PN2 levels that would cause a significant
proportion of DCS cases in terrestrial mammals. Cuvier’s beaked whale diving behaviour appears to put
them at higher risk than the other species, which may explain their prevalence in strandings after the use
of mid-frequency sonar.