Predatory diet composition based on identifiable prey items according to ecological depth groupings (epi, epipelagic; up.dvm, upper mesopelagic migrators; up.perm, upper mesopelagic nonmigrators; lo.dvm, lower mesopelagic migrators; lo.perm, lower mesopelagic migrators) (see Results and Discussion section of text for details). Diet is expressed as a function of the total gravimetric contribution of the prey (%W).