|Scientific Name:||Scoliodon laticaudus|
|Species Authority:||Müller & Henle, 1838|
|Red List Category & Criteria:||Near Threatened ver 3.1|
|Reviewer(s):||Musick, J.A. & Fowler, S.L. (Shark Red List Authority)|
This assessment is based on the information published in the 2005 shark status survey (Fowler et al. 2005).
The Spadenose Shark (Scoliodon laticaudus) is a small coastal shark which is abundant in the northern Indian Ocean and Southeast Asia. Despite being commonly caught in fisheries there are no data available on the status of the Spadenose Shark. It is likely that its life history will make it more resilient to fishing than larger, longer-lived, species of elasmobranchs. However, because of its limited fecundity concern exists that fishing will lead to recruitment overfishing.
|Range Description:||The Spadenose Shark is an abundant inshore species throughout Southeast Asia and north-eastern Africa. It occurs in the Indonesian archipelago as far as Java and Kalimantan. It is commonly recorded from the lower reaches of rivers in at least Malaysia, Sumatra and Borneo (Compagno 1984b).|
Native:Bangladesh; Brunei Darussalam; Cambodia; China; India; Indonesia; Japan; Macao; Malaysia; Myanmar; Oman; Pakistan; Philippines; Singapore; Somalia; Sri Lanka; Taiwan, Province of China; Thailand; Viet Nam
|FAO Marine Fishing Areas:||
Indian Ocean – eastern; Indian Ocean – western; Mediterranean and Black Sea; Pacific – western central
|Range Map:||Click here to open the map viewer and explore range.|
|Habitat and Ecology:||
The Spadenose Shark is a small species, growing to a maximum length of approximately 74 cm. It feeds mostly on small benthic fish, cephalopods, crabs and stomatopods (Setna et al. 1948, Compagno 1984b, Wang et al. 1996).
This shark is placentally viviparous, with arguably the most advanced reproductive mode of the elasmobranchs. Eggs are ovulated at only 1 mm in diameter and the stalked placenta forms when the embryos are only a few millimetres in length (Wourms 1993). The young are born at a length of 12-15 cm. Males mature at 24-36 cm and females at 33-35 cm (Devadoss 1979, Compagno 1984b). Breeding occurs throughout the year (Devadoss 1979) and females probably mate at least once each year. Litter sizes range from 6-18, with a mean of 13 (Devadoss 1979). The young are born throughout the year, after a gestation period of five or six months (Compagno 1984b).
There are limited age and growth data available for the Spadenose Shark. Nair (1976) and Kasim (1991) used length frequency data to estimate age and growth parameters. Nair (1976) estimated that they mature at one or two years of age, and that males live approximately five years and females six years. Kasim (1991) gave more rapid estimates of growth, producing growth curves that estimate the size of maturity being reached in less than six months. The use of length frequency data to estimate growth parameters, however, may be erroneous for the Spadenose Shark since the young are born throughout the year, making age-class identification problematic. Further work on the age and growth of this species using vertebral ageing and/or tag-recapture would prove useful.
Kasim (1991) used his growth data from length-frequency analysis to make estimates of natural mortality (M). Using the method of Pauly (1980) he estimated that M = 1.53 year-1 for females and M = 1.76 year-1 for males. He also estimated total mortality to be very high, in the range of 3.32 year-1 to 8.73 year-1. These estimates are very high and suggest that the methods or data used were inappropriate.
The abundance of this species in inshore waters makes it a major component of a variety of fisheries in Southeast Asia. For example, Kasim (1991) reported that the annual recorded catch of Spadenose Shark in the Verval coast, India from 1979-1981 averaged 823 t. This was taken mostly by trawl and gillnet fishing. Parry-Jones (1996) reported that the Spadenose Shark was the most commonly observed coastal species in Chinese market surveys. Unfortunately, there are no data available on the overall catch of this species, or the impact of fishing on stocks.
The occurrence of this species in estuarine and inshore areas may also make this species susceptible to the impacts of habitat degradation and modification. However, there are no data available on this subject.
|Conservation Actions:||There are no known conservation or management measures that apply specifically to this species.|
|Citation:||Simpfendorfer, C. 2009. Scoliodon laticaudus. The IUCN Red List of Threatened Species. Version 2015.2. <www.iucnredlist.org>. Downloaded on 07 July 2015.|