Stingray life history trade-offs associated with nursery habitat use inferred from a bioenergetics model

Abstract

Consumption rates of marine predators are vital to assessing their trophic impacts and potential consequences of fisheries removal and habitat alteration, yet are rarely estimated. Standard metabolic rates were estimated for juvenile brown stingrays, Dasyatis lata, and used as input parameters for a bioenergetics model to predict consumption rates. Temperature and mass had significant effects on metabolic rates. The energy budget of juvenile brown stingrays was heavily weighted toward metabolism, accounting for 66 % of consumed energy. Growth accounted for 7 % of the energy budget indicating very slow growth potentially due to limited food resources. Population consumption rates suggest potential for strong top-down effects on prey populations due to stingray predation. This study suggests the use of Kāne‘ohe Bay as a nursery habitat for juvenile brown stingrays is a trade-off between increased juvenile survival through predator avoidance and a late age at first maturity due to slow growth rates resulting from low prey availability.