Meeting Abstract
Although renowned for consuming large prey, sharks often undergo a series of profound dietary and habitat changes during their ontogeny that may constrain how certain species effectively capture and handle different prey types and sizes. Bite force production in some shark species has been observed to increase significantly from parturition through juvenile stages due to positive allometry of the jaw adducting mechanism. However, our knowledge regarding these patterns is limited to a few species and size classes. Bull (Carcharhinus lecuas), blacktip (Carcharhinus limbatus), and bonnethead (Sphyrna tiburo) sharks are common along the Texas coast, and recent data demonstrates that coastal habitats in Texas function as nurseries for these species. The goal of this study is to compare the biomechanics of bite performance and its constraints on the trophic ecology of these three species over their ontogenetic stages. Maximum gape, gape angle, and bite performance was measured in each species at several ontogenetic stages. In addition, body length and five girth measurements were collected to investigate scaling relationships with jaw morphology and bite performance. Theoretical bite force was calculated to discern relative changes in force production over time. Comparisons among all three species will begin to allow us to characterize the relative performance of their feeding apparatuses from a morphological and biomechanical perspective, as well as its effect on trophic ecology.
