The Last Frontier: Catch Records of White Sharks (Carcharodon carcharias) in the Northwest Pacific Ocean

Abstract

White sharks are highly migratory apex predators, globally distributed in temperate, sub-tropical, and tropical waters. Knowledge of white shark biology and ecology has increased recently based on research at known aggregation sites in the Indian, Atlantic, and Northeast Pacific Oceans; however, few data are available for the Northwest Pacific Ocean. This study provides a meta-analysis of 240 observations of white sharks from the Northwest Pacific Ocean between 1951 and 2012. Records comprise reports of bycatch in commercial fisheries, media accounts, personal communications, and documentation of shark-human interactions from Russia (n = 8), Republic of Korea (22), Japan (129), China (32), Taiwan (45), Philippines (1) and Vietnam (3). Observations occurred in all months, excluding October-January in the north (Russia and Republic of Korea) and July-August in the south (China, Taiwan, Philippines, and Vietnam). Population trend analysis indicated that the relative abundance of white sharks in the region has remained relatively stable, but parameterization of a 75% increase in observer effort found evidence of a minor decline since 2002. Reliably measured sharks ranged from 126–602 cm total length (TL) and 16–2530 kg total weight. The largest shark in this study (602 cm TL) represents the largest measured shark on record worldwide. For all countries combined the sex ratio was non-significantly biased towards females (1∶1.1; n = 113). Of 60 females examined, 11 were confirmed pregnant ranging from the beginning stages of pregnancy (egg cases) to near term (140 cm TL embryos). On average, 6.0±2.2 embryos were found per litter (maximum of 10) and gestation period was estimated to be 20 months. These observations confirm that white sharks are present in the Northwest Pacific Ocean year-round. While acknowledging the difficulties of studying little known populations of a naturally low abundance species, these results highlight the need for dedicated research to inform regional conservation and management planning.

First record of the white shark Carcharodon carcharias (Lamniformes: Lamnidae) from Sabah, Malaysian Borneo

“…The occurrence of C. carcharias off Sabah in AprilMay is consistent with the seasonal movements of the species in the Northwest Pacific inferred by Christiansen et al (2014). They reported C. carcharias during all months except July-August in the south (China, Taiwan, Philippines, and Vietnam), and all months except October-January in the north (Russia and Republic of Korea).…”

“…2). Carcharodon carcharias is widely distributed in the South China Sea (Compagno 2002;Compagno et al 2005;Christiansen et al 2014). Christiansen et al (2014) most southerly records were two reports from Qui Nhon Bay, Vietnam, and one from the Philippines.…”

“…Carcharodon carcharias is widely distributed in the South China Sea (Compagno 2002;Compagno et al 2005;Christiansen et al 2014). Christiansen et al (2014) most southerly records were two reports from Qui Nhon Bay, Vietnam, and one from the Philippines. One of the Vietnamese records was an unconfirmed media report of a 1.6 m TL juvenile, whereas the other was of a 5 m TL specimen (unknown sex) that was confirmed by a photograph (http://www.…”

“…Although intensively studied in the Southwest and Northeast Pacific Ocean, relatively little is known of the species in the Northwest Pacific (Compagno 2002;Bruce et al 2006;Domeier 2012;Duffy et al 2012). Christiansen et al (2014) reviewed 240 observations of white sharks from the Northwest Pacific concluding that although the species is not abundant, it is present in the region year round. The northernmost record of the species from the Northwest Pacific is from Tatar Strait, Sakhalin, Russia (47°19.45′ N, 141°25.74′ E), the southernmost is from the Bohol Sea, Philippines (c. 8°39.66′ N, 124°37.33′ E) (Herre 1953, Christiansen et al 2014.…”

“…Christiansen et al (2014) reviewed 240 observations of white sharks from the Northwest Pacific concluding that although the species is not abundant, it is present in the region year round. The northernmost record of the species from the Northwest Pacific is from Tatar Strait, Sakhalin, Russia (47°19.45′ N, 141°25.74′ E), the southernmost is from the Bohol Sea, Philippines (c. 8°39.66′ N, 124°37.33′ E) (Herre 1953, Christiansen et al 2014. In early 1981 a large white shark (Carcharodon carcharias) was photographed by commercial divers while laying an underwater pipeline from the barge E.T.P.M.…”