The Use of Stable Isotope Ecology in Sharks

Biochemical techniques such as Stable isotope analysis (SIA) are increasingly becoming a standard tool in many branches of ecology, especially those examining marine taxa and ecosystems. These techniques are used to provide information at a range of levels of biological organization from the organ, individual organisms, population, and species through to the ecosystem level. They are also used to inform our understanding of global biogeochemical cycles and environmental change. An emerging trend in marine conservation is “ecosystem-based fisheries management”, which means that managers would consider the diet and food web interactions of species of interest. An effective ecosystem-based fisheries management plan would require, among other things, detailed diet, and food web interaction data. We can better conserve and protect threatened marine life such as sharks if we better understand their biology and ecology, including what they eat. In the last two decades, the use of SIA to explore the trophic ecology of elasmobranchs has potentially increased. Many tissues such as blood, muscle, liver, vertebrae, and teeth have been utilized for stable isotope analysis studies of sharks to allow understanding of the role that they have in different temporal scales in the ecosystems. This special issue aims to highlight eco-trophic work on chondrichthyans that is being or has been done with SIA globally, and studies of Latin American shark populations will be particularly welcomed.