The Biology and Ecology of Thresher Sharks (Alopiidae)

Abstract

We review the biology and ecology of the three known species of thresher shark (Alopiidae) occurring in the Atlantic, Pacifi c, and Indian Oceans: the common thresher shark (Alopias vulpinus), bigeye thresher shark (A. superciliosus), and pelagic thresher shark (A. pelagicus). We also present revised data on age, growth, and sexual maturity of the common thresher shark off California. These new data suggest that off the US West Coast, male and female common threshers mature at ϳ303 cm total length (TL) and ϳ5 years of age. The revised von Bertalanffy growth model for combined data (N ϭ 315) produced parameter estimates of L ϱ ϭ 465 cm TL, K ϭ 0.129, and t 0 ϭ -2.88 (asymptotic length, the von Bertalanffy growth coeffi cient, and theoretical age at size zero, respectively). Average maximum reproductive age for females is estimated at around 25 years. These results suggest that the common thresher is the fastest-growing and earliest-maturing of the three species of thresher shark, and attains the largest size.

Pan-Atlantic distribution patterns and reproductive biology of the bigeye thresher, Alopias superciliosus

“…The size at maturity obtained in the present study reinforces that the bigeye thresher reaches maturity at a larger size than the other species of the Alopiidae family, as stated by Smith et al (2008a). Assuming that age at maturity is also reached at a later age (Fernandez-Carvalho et al 2011), and considering the very limited fecundity, the reproductive potential of the bigeye thresher is suggested to be very low when compared to other sharks more prevalent in the epipelagic-oceanic areas.…”

“…Similarly to the common thresher (Alopias vulpinus) and pelagic thresher (Alopias pelagicus), the litter size of the bigeye thresher is commonly two (rarely four) pups, though they grow more slowly and reach maturity at a later age than the other threshers (Moreno and Morón 1992;Mancini and Amorim 2006;Romero-Caicedo 2007;Smith et al 2008a). In addition, though the bigeye thresher typically occurs in temperate and tropical waters, they can endure colder water and remain longer at deeper waters than many other pelagic sharks (Gruber and Compagno 1981;Smith et al 2008a;IPMA, unpublished data).…”

“…Thresher sharks have an aplacental viviparous reproductive mode with oophagy, characterized by the developing embryos being nourished by yolk-filled egg capsules that are continuously produced and deposited in the uteri (Gruber and Compagno 1981;Moreno and Morón 1992;Gilmore 1993;Conrath 2004). Similarly to the common thresher (Alopias vulpinus) and pelagic thresher (Alopias pelagicus), the litter size of the bigeye thresher is commonly two (rarely four) pups, though they grow more slowly and reach maturity at a later age than the other threshers (Moreno and Morón 1992;Mancini and Amorim 2006;Romero-Caicedo 2007;Smith et al 2008a). In addition, though the bigeye thresher typically occurs in temperate and tropical waters, they can endure colder water and remain longer at deeper waters than many other pelagic sharks (Gruber and Compagno 1981;Smith et al 2008a;IPMA, unpublished data).…”

Late Miocene chondrichthyans from Lago Bayano, Panama: Functional diversity, environment and biogeography

“…Young individuals are often found close inshore and in shallow bays (Compagno et al, 1989;Compagno et al, 2005). Alopias vulpinus is frequently encountered in temperate waters and more common in coastal environments than any of the other thresher sharks (Smith et al, 2008 Type.-Eugaleus omanensis Norman, 1939(Cappetta, 2012.…”

Introduction to Sharks of the Open Ocean

“…Studies of shark catch rates from commercial fi sheries have found declines of thresher, blue, mako, and oceanic whitetip sharks in the Northwest Atlantic (Baum et al, 2003), although Nakano (1996) found that blue shark catch rates were stable in the Atlantic, as well as in the Pacifi c and Indian Oceans. There is evidence of a decline in an eastern Pacifi c population of common threshers followed by some rebuilding (Smith et al, 2008b). There is evidence of a decline in an eastern Pacifi c population of common threshers followed by some rebuilding (Smith et al, 2008b).…”