Fishers in Tawi-Tawi described horseshoe crabs scientists had not mapped there

Mongabay reported on November 6, 2026, that researchers have recorded horseshoe crabs in Tawi-Tawi, a southern Philippine province where the animals had not been on the scientific map. Until now, the country's records were from Palawan. The evidence is interviews, not a net full of specimens. Ivane Pedrosa-Gerasmio, of Mindanao State University–Iligan Institute of Technology, said people at a market in Bongao, the provincial capital, told her about the crabs when she visited in December 2023. She and student Quesie Tolero Omnos then asked 142 residents in Bongao, Simunul, Sitangkai, and Panglima Sugala where they see the animals, how often, and whether the numbers seem to be changing.

People described two forms, one resembling the endangered tri-spine horseshoe crab and one resembling the mangrove horseshoe crab, which is listed as data deficient. Locals call them bangkas, for a boat-like shape. Sightings were on sandy beaches, in mangroves, among rocky coral and seagrass, and in water 10 to 15 meters deep. Residents said the crabs are taken for medicine, including for asthma, and for rituals. More than half of those interviewed thought the animals were declining, and they mentioned collection, climate, and industrial pollution as possible reasons. Omnos told Mongabay that a management plan needs this kind of baseline first. The news is a first provincial record built from local knowledge. It is not a population census, and it does not show that the crabs are safe.