Our findings demonstrate how protected areas, most notably human exclusion areas (i.e. no-entry zones), may preserve natural or near natural behavioural traits in a population of large predatory reef fishes. However, the implications of preserved natural behaviour in a species have rarely been studied in this context (but see Biro and Post, 2008 Sih et al., 2012). Previous research on assortative mating in fish popula tions has described how females preferentially paired with bolder males if given a chance to observe the males' behaviours towards a predator (Godin and Dugatkin, 1996). Coral trout are polygymous and aggregate to spawn, wherein male individuals establish temporary breeding territories and attract females for mating through courtship displays (Samoilys and Squire. 1994). Accordingly, boldness towards compete tors and other predators may be beneficial for maintaining a breeding tenitory and for the transfer of genetic information to successive gener ations. Removal of these bold individuals may therefore modify both the natural social and genetic structure of coral trout, with implications that are yet unknown.