Consuming Costly Prey: Optimal Foraging and the Role of Compensatory Growth

Some prey are exceptionally difficult to digest, and yet even non-specialized animals may consume them—why? Durophagy, the consumption of hard-shelled prey, is thought require special adaptations for crushing or digesting hard shells avoid many potential costs this type. But lacking specializations nevertheless include hard-bodied in their diets. We describe several non-mutually exclusive adaptive mechanisms that could explain such a pattern, point optimal foraging compensatory growth as potentially having widespread importance explaining costly-prey consumption. first conducted literature survey quantify regularity with which teleost fishes prey: stomach-content data from 325 fish species spanning 82 families (57,233 stomach samples) demonstrated comprise ~75% total exhibiting durophagy, commonly consuming at low moderate levels (~10–40% much specialists). then performed diet assess frequency molluscivory across native latitudinal range small livebearing fish, Gambusia holbrooki , durophagy specializations. Molluscivory was regionally widespread, entire (>14° latitude). Third, we tested higher under conditions intraspecific resource competition Bahamian mosquitofish ( spp.). Examining over 5,300 individuals, found more common populations population density, suggesting food limitation important eliciting molluscivory. Finally, experimentally G. whether reduces rate follows period gastropods results significantly reduced rate, but following prior snail can quickly mitigate costs. Our suggest phenomenon be partially explained by its relative benefits when few alternative options exist, combined alleviates temporary