More stingrays, fewer sharks for sale at S'pore's fishery ports, say researchers
A whitespotted whipray being sold alongside other species of fish at Jurong Fishery Port.
SINGAPORE - Two researchers in Singapore have in recent years observed an unexpected trend at Singapore's fishery ports: There are fewer sharks, but a rising number of stingrays being sold.
Both sharks and stingrays have similar life history traits that make them vulnerable to overharvesting. They take several years to reach reproductive age, and produce few offspring. But more attention is usually paid to the plight of sharks, which are prized for their fins, especially in Asia.
Now, research by independent shark and stingray researchers Naomi Clark-Shen and Kathy Xu shows that stingrays, too, could be suffering from overharvesting.
Through visits to Singapore's fishery ports, they found that the number of stingrays there had almost doubled over the years.
They counted 6,984 stingrays in the first year of their surveys, from September 2017 to September 2018. This rose to 11,649 between March 2024 and March 2025.
In the same period, the number of sharks counted fell from 1,470 to 933.
The duo conducted surveys at Jurong Fishery Port twice a month. The researchers also included figures from Senoko Fishery Port in their counts prior to its
closure in March 2024.
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They said that two species of stingrays were especially common: the whitespotted whipray (Maculabatis gerrardi) and sharpnose whipray (Maculabatis macrura).
The researchers counted 5,806 stingrays from both species from 2017 to 2018, and 8,598 stingrays from 2024 to 2025.
The two species – both globally endangered – are often sold in hawker centres as sambal-laden barbecue stingray.
Sharks and stingrays belong to a group known as elasmobranchs, which also includes wedgefish and guitarfish.
The pair said that when they first started the port surveys in 2017, they used to see hundreds of wedgefish, guitarfish, sharks and stingrays.
But after greater protection was granted to wedgefish, guitarfish and sharks under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (Cites), they started showing up less frequently in Singapore's fishery ports.
Cites governs the international trade in wildlife parts and products. In 2022, 60 species of sharks were listed on Appendix II of Cites. This means that trading these species internationally would require permits from exporting countries.
All 10 species of wedgefish and the six species of guitarfish were similarly listed on Cites Appendix II in 2019.
Dr Clark-Shen said: 'The fishermen who used to catch (endangered) fish species may find another market if they are listed on Cites, whether it's the black market, or selling their catch within their own country for a reduced price, causing local consumption to pick up.'
Dr Clark-Shen and Ms Xu said the imposition of trade regulations on some species may also have ripple effects on species that are less protected. The whitespotted whipray and sharpnose whipray, for example, are not protected under Cites' regulations, which means that no permits are needed for their trade.
A stingray vendor at the Jurong Fishery Port who declined to reveal his name told The Straits Times that he sells between 400kg and 600kg of stingrays on a weekday, and up to 1,000kg of the fish in a day during the weekend.
He said: 'In the past, we used to source stingrays only from Malaysia, and could take 1,000kg or 2,000kg per day.
'But when many other vendors began selling them, we started including stingrays from Jakarta, Surabaya, Bangka and other small islands in Indonesia.'
The vendor added that he takes in only female stingrays under 3kg in mass, as males tend to smell more strongly of ammonia, and younger rays tend to have softer and more tender meat.
Mr Melvin Wee, 56, a seafood supplier who has worked in the industry for about 40 years, said that aside from a possibly growing supply, local demand for stingray in Singapore has also increased.
He pointed to the rise in popularity of the sambal stingray as a contributing factor, saying this dish appeared in local markets about 30 years ago.
Dr Mark Erdmann, vice-president of Asia-Pacific marine programmes at Conservation International, a global environmental non-profit organisation, said that the data from Singapore's fishery ports highlights the urgency for stingrays to be better protected.
Dr Erdmann said: 'It is well-known that the demand for shark fin has decreased dramatically over the past decade – in part due to increased awareness of the negative impacts of shark fin consumption, but also due to strengthened international trade controls.
'But a large number of ray species are now considered to be threatened with extinction, due to the increasing numbers being landed in Singapore and South-east Asia.'
He said: 'Simply put, they cannot be harvested at a commercial level in a way that could ever be defined as sustainable, and should hence not be consumed – it's the marine equivalent of putting sun bears or sugar gliders on the menu.'
Unlike bony fishes, which can lay millions of eggs at a time, stingrays and sharks give birth to only a few live young each year.
The two whipray species commonly found here reach maturity between four and nine years old, and give birth to only one to five offspring each time, according to a paper published in March 2025, which the two researchers co-authored alongside a team of scientists.
Dr Anna Wong, the senior director of wildlife trade at the National Parks Board, said consumers are advised to adopt more sustainable alternatives, or opt for other dishes altogether. 'If members of the public must consume sharks and rays, they should always check the source of origin and species being harvested to ensure that they are not a Cites-listed species before consumption.'
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