All about the bottlenose: an Endangered wedgefish in Malaysia

  • Sharks
Years funded
  • 2021
  • Active
Project types
  • Conservation
  • Research
  • Universiti Malaya

Amanda visits crowded landing sites to collect genetic samples and talk to local fishers to understand their perspective on catching bottlenose wedgefish (also called whitespotted wedgefish). Her project aims to determine the local population structure and fishery threats of the bottlenose wedgefish (Rhynchobatus australiae) in Malaysia. To do this, she’s using fish landing site surveys and face-to-face interviews to understand which fishing gear are used, and assess catch profile information. Amanda is doing DNA analyses is to clarify the genetic structure of this species. She hopes her work will inform conservation actions and provide gear-specific management actions to protect this endangered species.

All about the bottlenose: an Endangered wedgefish in Malaysia

Amanda Jhu Xhin Leung

Project leader
About the project leader

I grew up in Kuala Lumpur, the capital of Malaysia and a city some distance from the ocean, yet ever since I was a kid I have been fascinated by marine life after watching wildlife documentaries. When I was 12 my passion for marine life burgeoned after my first visit to Underwater World Langkawi, an aquarium in Malaysia. For me, it was an eye-opener to see those amazing marine creatures. As my interest in the marine environment grew, I went on to pursue a BSc degree in aquatic resource science and management at the University of...

Project details

Population Structure and Fishery Threats of Endangered bottlenose wedgefish in Malaysia

Key objective

The aim of this project is to advance science-based management of R. australiae. Specifically, the project will clarify the genetic structure and population connectivity of endangered R. australiae between different regions of Malaysian waters and determine the rank of fishing gear threats, especially by small scale fisheries, to the animals.

Project activities will be carried out in Malaysia, one of the top shark fishing nations in the world. Specifically, surveys will be done along both coasts of the Malay Peninsula and the Malaysian Borneo. Focus will be given on major fishing landing sites where sightings of Rhynchobatus australiae had been previously recorded.

Why is this important

Rhynchobatus australiae is one of the top ten species of rays caught in Malaysia and prized for their fins and meat. They are often caught as bycatch and also targeted in commercial fisheries, which undermines the threats faced by R. australiae. By determinig the degree of genetic connectivity and population structure of this species and the fishing gear(s) that pose the greatest threat to the animals will be important to inform fishery management actions.


Rhynchobatus australiae, also known as the white-spotted wedgefish, can be found throughout the Indo-West Pacific area ranging from Thailand, Taiwan, Philippines, and Indonesia to Australian subtropics. As a member of the highly-threatened family of Rhinidae, R. australiae is very vulnerable to overfishing because the species has relatively slow reproductive rates, large body size and inhabits shallow coastal waters where multiple fishing gears operate throughout its range. Little else is known about the fine-scale population genetics and connectivity of this highly exploited species in Malaysia which is part of the Sundaland bioregion.

The IUCN Red List of Threatened Species has recently reclassified all wedgefish species including R. australiae as ‘Critically Endangered’. This raises a huge concern as R. australiae is not legally protected in Malaysia. The absence of species-specific landing data and other relevant studies aggravate the issue where the threats to this species are going unrecognized. Although commercial fishery operations especially trawlers are often seen as culprits in overfishing local fish populations, the impact of small scale artisanal fisheries operating in nearshore waters where R. australiae inhabit is much less known. This project, therefore, aims to advance science-based advocacy for the protection of the animals by addressing essential research gaps. Specifically, the project aims to clarify the degree of population connectivity and population structure of R. australiae using molecular tools, and also objectively evaluating fishery threats of both commercial and artisanal fisheries towards the poorly studied species.

Aims & objectives
  • To elucidate the genetic structure and population connectivity of Rhynchobatus australiae between different regions of Malaysia
  • To determine the rank of fishing gear threats, especially by small scale fisheries, to Rhynchobatus australiae in Malaysia