PT  - JOURNAL ARTICLE
AU  - Frida Lara-Lizardi
AU  - Mauricio Hoyos-Padilla
AU  - Alex Hearn
AU  - A. Peter Klimley
AU  - Felipe Galván-Magaña
AU  - Randall Arauz
AU  - Sandra Bessudo
AU  - Eleazar Castro
AU  - Eric Clua
AU  - Eduardo Espinoza
AU  - Chris Fischer
AU  - César Peñaherrera-Palma
AU  - Todd Steiner
AU  - James T. Ketchum
TI  - Shark movements in the Revillagigedo Archipelago and connectivity with the Eastern Tropical Pacific
AID  - 10.1101/2020.03.02.972844
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.03.02.972844
4099  - http://biorxiv.org/content/early/2020/03/02/2020.03.02.972844.short
4100  - http://biorxiv.org/content/early/2020/03/02/2020.03.02.972844.full
AB  - Long-distance movements of sharks within and between islands pose substantial challenges for resource managers working with highly migratory species. When no-take zones do not cover the critical areas that sharks use as part of their lifecycle, exposure to fishing activities can be significant. Shark movements between the Marine Protected Areas (MPAs) of the Eastern Tropical Pacific (ETP) have been studied for several years, however little is known about the strength of connectivity between these islands. We analyzed the extensive MigraMar ultrasonic telemetry dataset to assess how Galapagos sharks (Carcharhinus galapagensis) and silky sharks (Carcharhinus falciformis) use different islands as stepping-stones during their migrations within the Revillagigedo National Park and other ETP islands. Of the 66 sharks monitored, 63.5% moved within the same island, 25.4% between two islands or more and only 10.1% across different MPAs. A C. falciformis tagged in Roca Partida Island, Revillagigedo, travelled to Clipperton Atoll and another one tagged in Darwin Island travelled to the atoll on two different years. The largest movement of C. galapagensis was accomplished by a shark tagged at Socorro Island, Revillagigedo, later detected at Clipperton and finally recorded in Darwin Island, Galapagos. This last path was in fact, one of the longest movements ever recorded for the species. Although long-distance dispersion was not common, our results highlight the need for co-operation between different countries to ensure adequate protection for sharks in the form of swimways and other conservation tools in the ETP.