Alopias pelagicus



The Pelagic Thresher (Alopias pelagicus) is listed by the IUCN on its Red List of Threatened Species as Vulnerable to extinction globally, due to severe, continued declines in their populations around the world.

A. pelagicus is truly oceanic (primarily inhabiting the open ocean) and wide-ranging throughout the Indo-Pacific, Australasia region north to Japan, and the Pacific coast of Mexico and northern South America. It has not been recorded in the Atlantic Ocean (Compagno 1984). Few data are available for A. pelagicus throughout its epipelagic range. It is not known whether Indian and Pacific Ocean populations are isolated although it is considered likely that this species migrates between Central America and the Gulf of California.

 Alopias spp.exhibit particularly low productivity and growth rates meaning they have a high susceptibility to anthropogenic pressure and show slow recovery from overexploitation. Data are scarcer for A. pelagicus, which is the smallest of the thresher sharks, reaching up to 375cm in length. They have an average litter size of 2 and females reach sexual maturity at 8-9 years and males at 7-8 years (Amorim et al., Goldman et al., Reardon et al. – IUCN Red List Assessments for Alopias spp.).

Alopias sppare caught and killed in both target and bycatch fisheries in domestic waters and the high seas globally. Catch is often unmanaged or only managed over part of their range. Alopias spp. fins are an important component of the global shark fin trade, with the last comprehensive study of the trade identifying them as accounting for approximately 2.3 % of sharks in the Hong Kong market. This is equivalent to up to four million thresher sharks per year (Clarke et al. 2006 A and B).



Assessment information
CMS InstrumentsCMS, Sharks (2016)
IUCN StatusVulnerable
Date of entry in Appendix II2014
Geographic range
Countries Australia, China, Ecuador, Egypt, Eritrea, French Polynesia, India, Indonesia, Iran, Japan, Kenya, Madagascar, Mexico, Micronesia, Mozambique, New Caledonia (France), Oman, Pakistan, Saudi Arabia, Somalia, South Africa, Sri Lanka, Sudan, Swaziland, United Republic of Tanzania, United States of America, Yemen
Common names
EnglishPelagic Thresher Shark
Scientific name Alopias pelagicus
AuthorNakamura 1935
Standard referenceEschmeyer, W.N. (1990). Catalogue of the Genera of Recent Fishes. California Academy of Sciences, San Francisco, California.

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