Nature Ecology & Evolution
Ecosystem ecology, Marine biology, Stable isotope analysis
Sharks are a diverse group of mobile predators that forage across varied spatial scales and have the potential to influence food web dynamics. The ecological consequences of recent declines in shark biomass may extend across broader geographic ranges if shark taxa display common behavioural traits. By tracking the original site of photosynthetic fixation of carbon atoms that were ultimately assimilated into muscle tissues of 5,394 sharks from 114 species, we identify globally consistent biogeographic traits in trophic interactions between sharks found in different habitats. We show that populations of shelf-dwelling sharks derive a substantial proportion of their carbon from regional pelagic sources, but contain individuals that forage within additional isotopically diverse local food webs, such as those supported by terrestrial plant sources, benthic production and macrophytes. In contrast, oceanic sharks seem to use carbon derived from between 30° and 50° of latitude. Global-scale compilations of stable isotope data combined with biogeochemical modelling generate hypotheses regarding animal behaviours that can be tested with other methodological approaches.
Christopher S. Bird, Ana Verissimo, Sarah Magozzi, Katya G. Abrantes, Alex Aguilar, Hassan Al-Reasi, Adam Barnett, Dana M. Bethea, Gerard Biais, Asuncion Borrell, Marc Bouchoucha, Mariah Boyle, Edward J. Brooks, Juerg Brunnschweiler, Paco Bustamante, Aaron Carlisle, Diana Catarino, Stephane Caut, Yves Cherel, Tiphaine Chouvelon, Diana Churchill, Javier Ciancio, Julien Claes, Ana Colaço, Dean L. Courtney, Pierre Cresson, Ryan Daly, Leigh de Necker, Tetsuya Endo, Ivon Figueiredo, Ashley J. Frisch, Joan Holst Hansen, Michael Heithaus, NIgel E. Hussey, Johannes Iitembu, Francis Jaunes, Michael J. Kinney, Jeremy J. Kiszka, Sebastian A. Klarian, Dorothee Kopp, Robert Leaf, Yunkai Li, Anne Lorrain, Daniel J. Madigan, Aleksandra Maljkovic, Luis Malpica-Cruz, Philip Matich, Mark G. Meekan, Frederic Menard, Gui M. Menezes, Samantha E. M. Munroe, Michael C. Newman, Yannis P. Papastamatiou, Heidi Pethybridge, Jeffrey D. Plumlee, Carlos Polo-Silva, Katie Quaeck-Davis, Vincent Raoult, Jonathan Reum, Yassir Eden Torres-Rojas, David S. Shiffman, Oliver N. Shipley, Conrad W. Speed, Michelle D. Staudinger, Amy K. Teffer, Alexander Tilley, Maria Valls, Jeremy Vaudo, Tak-Cheung Wai, R. J. David Wells, Alex S. J. Wyatt, Andrew Yool, and Clive N. Trueman. 2018. A Global Perspective on the Trophic Geography of Sharks .Nature Ecology & Evolution , (2) : 299 -305. https://nsuworks.nova.edu/occ_facarticles/912.