For nearly 20 years, the blue-spotted bamboo shark, found only in Madagascar, went scientifically undetected and unrecorded. But researchers have now found four new records of the “lost” shark while surveying fishing villages and a Malagasy university’s fish collection. These recent records, and interviews with fishers, suggest the species may be more common than previously thought, according to a new study.
The blue-spotted bamboo shark (Chiloscyllium caeruleopunctatum), so named for the blue-white spots on its brown body, was first described based on a specimen caught off Madagascar in 1914. A second record of the species came 92 years later — a photograph of a shark caught in 2006.
Since then, the species largely went unconfirmed, until researchers began surveying fish markets and landing sites in Madagascar in September 2025.
Study lead author Tsarahasina Fanomenzana, a young Malagasy intern from the NGO Madagascar Whale Shark Project, was showing photos of sharks and rays he’d seen at a fishing village on the east coast to shark expert and study co-author David Ebert.
“One of the photos was of the blue-spotted bamboo shark,” Ebert told Mongabay by email. “He didn’t think too much of it as there were some other images of shark and ray species he thought were more interesting.”
However, Ebert said he was “more than excited,” because the pictures confirmed the blue-spotted shark was still around. He was in Madagascar for the Lost Sharks project, supported by the Save Our Seas Foundation, which aims to find and raise awareness about little-known shark and ray species that could be disappearing unnoticed.
Ebert and his colleagues eventually confirmed two more individuals of the shark from the fishing village, and a fourth specimen housed in the University of Tulear’s fish collection, on the west coast. “Since these new records were published I have had some more evidence in the forms of photos come out further confirming this species,” Ebert said.
The blue-spotted bamboo shark is currently listed as data deficient on the IUCN Red List, meaning not enough is known about the species to determine its conservation status.
The lack of information could partly be because the species is sometimes misidentified as the white-spotted bamboo shark (Chiloscyllium plagiosum), “so most Malagasy’s do not realize that it is endemic to Madagascar,” Ebert said.
He added that interviews with fishers revealed they also mistake it for young leopard sharks, also called zebra sharks (Stegostoma tigrinum).
“So, I believe now that [the blue-spotted bamboo shark] is more common than previously thought, but due to its being misidentified it has been underreported,” Ebert said. “Hopefully, now that people in Madagascar are more aware of it, they will start to note its occurrence going forward.”
Ebert added that whether these additional new records will prompt the IUCN, the global wildlife conservation authority, to revisit the shark’s conservation status is unclear, “but hopefully we can build more information for the future such that when the time does come to review it, we might be able to elevate the assessment.”
Banner image: A blue-spotted bamboo shark photographed in Madagascar in 2025. Image courtesy of Tsarahasina Fanomenzana.
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