The sawfish, recognizable by its distinctive saw-shaped snout or rostrum, is now thought to be “functionally extinct” in Sri Lankan waters. This, researchers say, means that while a few individuals may still exist, their numbers are likely too low to maintain a viable breeding population, reports contributor Malaka Rodrigo for Mongabay.
In a 2021 study, researchers from the Colombo-based nonprofit Blue Resources Trust (BRT), interviewed 300 fishers across 21 harbors to assess the status of the species. The results showed a stark generational gap.
While fishers over the age of 50 remembered sawfish as once abundant, none of the fishers under the age of 30 could even identify the animal from photographs, Akshay Tanna with the BRT told Mongabay. He added that roughly half of the older fishers who had seen one had not encountered a sawfish since 1992.
The last confirmed record of a sawfish in Sri Lanka, the researchers found, was a chance encounter in 2017 off the eastern coast, when a fisher had photographed the animal and framed its picture.
Marine biologist and study co-author Sahan Thilakaratna said three of five species of sawfish have historically been recorded in Sri Lankan waters: the narrow sawfish (Anoxypristis cuspidata), the largetooth sawfish (Pristis pristis) and the green sawfish (P. zijsron). All are currently listed as critically endangered on the IUCN Red List. Globally, their decline is driven by overfishing, habitat loss and bycatch. The sawfish’s rostrum, which it uses as a sensory organ and weapon to hunt, easily becomes entangled in fishing nets, making them highly vulnerable to accidental capture.
Recovery for these rays is particularly challenging due to their biology: they grow slowly, mature late, and produce few offspring, said Rima Jabado, chair of the Shark Specialist Group at the IUCN, the global wildlife conservation authority. However, researchers say there’s a ray of hope.
Thilakaratna recorded a fisher who had caught a juvenile sawfish in brackish waters in Balapitiya in southern Sri Lanka nearly a decade ago, suggesting that refuges for the species might still exist. “Sawfish do use brackish habitats as breeding and nursery grounds, and these environments are critical for their survival,” he said.
Thilakaratna also found cultural records that suggest there’s potential for community-based conservation actions for the sawfish. He visited churches in coastal fishing communities where he saw preserved sawfish rostra presented as offerings. “Fishers offer the sawfish rostra to churches as acts of gratitude or for protection at sea,” he said.
To prevent the sawfish’s local extinction, Jabado called for coordinated conservation efforts, including protecting key estuarine habitats, incentivizing fishers to release bycatch, and strengthening science-based policies. She added these measures could also support the recovery of sawfishes and other threatened rays such as guitarfishes and wedgefishes.
Read the full story by Malaka Rodrigo here.
Banner image of a largetooth sawfish at the Georgia Aquarium. Image by David Iliff via Wikimedia Commons (CC BY-SA 3.0).
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