Several studies have now demonstrated density dependence and the potential for population regulation as an important process in post-settlement mortality of reef fishes. Because reef fishes (like many organisms) occupy particular habitats, the role of habitat structure and complexity in mediating predator foraging success and potentially altering per capita mortality can be important in modifying mortality.

Todd Anderson, Andres Deza, and Kevin O'Connor  investigated experimentally the effects of a  piscivore, the kelp bass, Paralabrax clathratus, on recruitment success of young kelp bass that associate strongly with algal habitats. Large field pens that enclosed kelp were deployed with large or small predators as treatments within pens to manipulate predator size and its effect on recruitment. Recruitment in pens with large predators was half that in pens with small predators. In addition, the size distribution of recruits differed between treatments, with smaller fish being more prevalent in pens with larger predators despite the fact that all of these predators were not limited by gape size. Laboratory experiments manipulating three sizes of kelp bass as predators and three or two sizes of recruit kelp bass or senorita, respectively, showed differential predation as a function of recruit size. Surveys of recruitment within (larger predators) and outside (smaller predators) of a marine protected area revealed that the abundance of recruits and their size distributions between these two areas reflected the results obtained in field and laboratory experiments based on predator size.