The Smoothnose Wedgefish (Rhynchobatus laevis) is a medium-sized (to >200 cm total length) shark-like ray which is widespread in the Indo-West Pacific from the Arabian Sea and the Bay of Bengal in the Indian Ocean, and off China and Japan in the Western Pacific. 

Biology

Length: Maximum size is thought to be >200 cm total length (TL); males mature at ~130 cm TL. 

Gestation Period: Unknown

Litter Size: Small but unknown

Life Expectancy: Generation length is estimated as 15 years.

Diet: It is poorly known but probably feeds on bottom-dwelling crustaceans and fishes.

Habitat and distributions

Habitat: The Smoothnose Wedgefish occurs from close inshore to depths of at least 60 m on the continental shelf and has a preference for shallow bays and river mouths.

Distribution: The Smoothnose Wedgefish is widespread in the Indo-West Pacific; it was first described from India and has been widely confused with the Western Indian Ocean Rhynchobatus djiddensis across its range from the Arabian Sea to the Western Pacific. It was previously thought to occur in East Africa, throughout Southeast Asia, and across northern Australia, but it is now considered to occur in the Arabian Sea and the Bay of Bengal in the Indian Ocean, and off China and Japan in the Western Pacific. The species' distribution may not be fully defined due to confusion with other members of the R. djiddensis species-complex.

Depth: 0-60 m

Landing sites: Mumbai, Malvani, Veraval, Mangrol, Porbander, Okha, Mangaluru and Malpe Fisheries Harbours

Commercial Value

Wedgefishes are heavily utilized across their range for the meat and fins. While little species-specific information is available, the following provides a generalized account of use and trade globally. The meat is of good quality and a food source for many coastal communities in tropical countries where it is generally consumed locally, although it also enters the international trade in dried and salted form. Large whole wedgefishes (>200 cm total length; TL) have been traded for a high value of up to US$680 each, however, smaller specimens can sell for low value. The ‘white’ fins of shark-like rays (including wedgefishes and giant guitarfishes) are considered the best quality fins for human consumption and are among the highest valued in the international shark fin trade. Fin prices in the literature include US$396/kg for wedgefish fins and an average price of US$276/kg and US$185/kg for Qun chi (fins from shark-like rays) in Guangzhou (mainland China) and Hong Kong, respectively. The skin may be dried and traded internationally as a luxury leather product. The eggs of shark-like rays are sometimes dried and consumed locally while the heads may also be dried and used as either fish meal or fertilizer.

Threats

There is a high level of fisheries resource use and increasing fishing pressure across the range of the Smoothnose Wedgefish, and demersal coastal fisheries resources have been severely depleted in significant areas of the Indo-West Pacific, including India and Southeast Asia.

References

Bonfil, R. and Abdallah, M. (2004) 
Field identification guide to the sharks and rays of the Red Sea and Gulf of Aden. FAO Species Identification Guide for Fishery Purposes. FAO, Rome.

Jabado, R.W. (2018) 
The fate of the most threatened order of elasmobranchs: Shark-like batoids (Rhinopristiformes) in the Arabian Sea and adjacent waters. Fisheries Research 204: 448–457.

Last, P., White, W., de Carvalho, M., Séret, B., Stehmann, M. and Naylor, G. (2016) 
Rays of the World. CSIRO Publishing, Clayton.

Last, P.R. and Stevens, J.D. (2009) 
Sharks and Rays of Australia. Second Edition. CSIRO Publishing, Collingwood.

Mohamed, K.S. and Veena, S. (2016) 
How long does it take for tropical marine fish stocks to recover after declines? Case studies from the Southwest coast of India. Current Science 110: 584–594.

Moore, A.B.M. (2017) 
Are guitarfishes the next sawfishes? Extinction risk and an urgent call for conservation action. Endangered Species Research 34: 75–88.