All we know about the crocodile shark (Pseudocarcharias kamoharai): Providing information to improve knowledge of this species

Abstract

Despite their global distribution across major oceans, biological and fisheries information related to the crocodile shark (Pseudocarcharias kamoharai) is still scarce. The crocodile shark has become a frequently observed bycatch shark in many commercial fisheries. Their catch rates might be underreported by commercial fisheries, maybe because of the species’ small size and low commercial value. Moreover, stock assessment of crocodile shark has not yet been conducted, greatly due to lack of data, and their stock status, movement and genetic connectivity are still poorly known. Previous works have shown that crocodile shark has a low reproductive rate (often 4 pups reported), therefore, fishing mortality caused by fisheries targeting economic important species such as tuna, may cause their population to greatly decline. Major tuna Regional Fishery Management Organization (RFMO), have implemented non-retention of shark species. However, specific measures related to crocodile shark is lacking. Even though it is listed as Least Concern by the International Union for the Conservation of Nature (IUCN) Red List, effort must be directed towards the conservation and management of its population in their range of habitat. In other to avoid a stock collapse for this species in the future, this work summarized existing information on the state of the fishery and biology information for this species and have proposed future research directions to fill in missing information gaps to conserve this crocodile shark’s population from declining as has been the case with many other shark species.