# Horseshoe Crab Population Discovered in Tawi-Tawi Province Researchers confirm new habitat for endangered horseshoe crabs through local community interviews. - **Source:** [Mongabay](https://news.mongabay.com) - **Published:** 2026-11-06 - **Topic:** [science](https://brifing.si/c/science) - **Original article:** - **On Brifing:** https://brifing.si/s/c38b36ce-f147-4757-90da-096e3943b9c3 ## New Habitat Discovery Researchers have officially confirmed the presence of horseshoe crabs in the southern Philippine province of Tawi-Tawi. This discovery marks a significant expansion from their previously known range, which was limited to Palawan province. The findings were established through extensive interviews with local fishers and coastal residents conducted by marine science experts. ## Species Identification Local residents identified two distinct species that resemble the tri-spine horseshoe crab and the mangrove horseshoe crab. The tri-spine variety is currently classified as endangered on the IUCN Red List, while the mangrove species remains listed as data deficient. These classifications highlight the urgent need for accurate population monitoring in the region. ## Research Origins The investigation began in December 2023 when associate professor Ivane Pedrosa-Gerasmio visited a market in Bongao, the capital of Tawi-Tawi. After hearing local accounts of the arthropods, she collaborated with student Quesie Tolero Omnos to verify the reports. They aimed to establish baseline information to support future science-based conservation initiatives for these species. ## Community Engagement Strategy The research team prioritized local knowledge by surveying 142 residents across four different municipalities in Tawi-Tawi. These participants provided critical data regarding the frequency of sightings, perceived population changes, and local consumption habits. Relying on coastal residents allowed the scientists to gather insights that would have been difficult to obtain through traditional surveys. ## Conservation Challenges The mangrove horseshoe crab's status as data deficient presents a major hurdle for environmental protection efforts. Because little is known about its population trends or ecological requirements, the Tawi-Tawi findings provide a vital starting point. Researchers hope this data will eventually lead to more robust regional policies aimed at protecting these vulnerable marine arthropods. ## Ecological Significance Horseshoe crabs are ancient marine arthropods that play a unique role in coastal ecosystems. Their presence in Tawi-Tawi suggests that the province may serve as a critical refuge for these creatures. Understanding their distribution is essential for maintaining biodiversity and ensuring that human activities do not further threaten their survival in the Philippines. ## Future Research Directions The team from Mindanao State University – Iligan Institute of Technology intends to use this initial study as a foundation for broader conservation projects. Future efforts will likely focus on quantifying population numbers and assessing the impact of local harvesting practices. This systematic approach is necessary to develop effective, long-term management strategies for habitats. ## Broader Environmental Impact This study underscores the importance of integrating traditional ecological knowledge into modern scientific research. By documenting the presence of endangered species in new areas, scientists can better advocate for protected status and habitat preservation. The Tawi-Tawi discovery serves as a reminder that many coastal regions remain under-studied, hiding critical information about global biodiversity. ## Sources covering this story - https://news.mongabay.com/short-article/2026/11/scientists-confirm-horseshoe-crabs-in-a-second-philippine-province-urge-conservation/ — --- _Summary written by Brifing from the original reporting. Copyright in the original article belongs to its publisher; read the full piece at the link above._