![]() ![]() ![]() Predation has also inhibited recovery of depleted species, sometimes through predator–prey role reversals. ![]() Conversely, abundant oceanic predators have suppressed prey abundances. Substantial reductions in marine mammals, sharks, and piscivorous fishes have led to mesopredator and invertebrate predator increases. ![]() In these ecosystems, where controlled manipulations are largely infeasible, ‘pseudo-experimental’ analyses of predator–prey interactions that treat independent predator populations as ‘replicates’, and temporal or spatial contrasts in predator populations and climate as ‘treatments’, are increasingly employed to help disentangle predator effects from environmental variation and noise. Here we synthesize the evidence for oceanic top-down control that has emerged over the last decade, focusing on large, high trophic-level predators inhabiting continental shelves, seas, and the open ocean. Top-down control can be an important determinant of ecosystem structure and function, but in oceanic ecosystems, where cascading effects of predator depletions, recoveries, and invasions could be significant, such effects had rarely been demonstrated until recently. ![]()
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