Occurrence and Bycatch of Juvenile and Neonate Whale Sharks (Rhincodon typus) in Peruvian Waters1

Abstract

In the eastern Pacific Ocean, whale sharks (Rhincodon typus) have mostly been studied off the Galapagos Islands, Ecuador, and Baja California, Mexico. Recently, satellite telemetry data revealed connectivity between whale sharks off the Galapagos Islands and Peru. Historic and some recent observations have reported rare occurrences of whale sharks in waters off northern Peru. However, no current detailed information on the occurrence of whale sharks in Peruvian waters has been published. In this study we compiled 27 records of whale sharks along the Peruvian coast as a first step to better understand their use of Peruvian waters. Northern Peru was identified as the main area of occurrence for whale sharks, and reports were more frequent during the austral summer (January to March) and spring (October to December). Moreover, presence of neonatal whale sharks reported in this study, in addition to that of previously satellite-tracked presumably pregnant females, suggests use of northern Peruvian waters as a pupping ground. Interactions occurred only with net fisheries and were evident in most (89%) of the records, but further studies should evaluate the extent of fisheries-shark interactions. As whale shark population numbers decline, effective conservation measures will require understanding of whale shark occurrences, and waters of northern Peru may play an important role in the species' biology and ecology. Systematic research is recommended to improve our understanding of habitat use of individuals present in Peruvian waters.