The Department of Agriculture-National Fisheries Research and Development Institute (DA-NFRDI), through its Philippine Aquatic Red List Committee (PARLC) Project, conducted a five-day boat-based survey to document the occurrence, population, and habitat use of the critically endangered Irrawaddy dolphin (Orcaella brevirostris) on September 14-18, 2026 in Malampaya Sound, Taytay, Northern Palawan.

The survey was conducted under the NFRDI project “Assessment of Entanglement and Bycatch Risk of Marine Mammals in Blue Swimming Crab Fishing Gears,” in collaboration with Marine Wildlife Watch of the Philippines (MWWP), World Wide Fund for Nature Philippines (WWF-Philippines), and the Protected Area Management Office of the Malampaya Sound Protected Landscape and Seascape (PAMO-MSPLS).

The activity aimed to generate updated information on the occurrence, population size, distribution, and habitat use of Irrawaddy dolphins in the Inner Malampaya Sound. The survey covered waters off Pancol, Old Guinlo, New Guinlo, Alacalian, and Banbanan, with researchers conducting up to 12 hours of onboard observations each day.

The team used line-transect observations, photo-identification, GPS recording, and environmental measurements to document dolphin encounters, identify individual dolphins, map their distribution, and assess habitat conditions.

Six dolphin sightings were recorded during the survey. These included 12-15 Indo-Pacific bottlenose dolphins (Tursiops aduncus), including a calf, observed near the boundary of the Inner and Outer Malampaya Sound. The remaining sightings involved Irrawaddy dolphins, recorded in groups of one to five individuals.

Among the Irrawaddy dolphin sightings, two individuals were re-sighted from previous surveys, while two new individuals were documented. These preliminary findings are subject to further analysis and comparison with the existing Malampaya Sound photo-identification catalogue.

The team also recorded GPS coordinates and measured dissolved oxygen, total dissolved solids, pH, salinity, and water temperature at designated stations. These data will help assess habitat conditions and examine the spatial distribution of Irrawaddy dolphins within the Inner Sound.

Fishing activities were also documented within known Irrawaddy dolphin habitat. Crab nets were observed in shallow waters, while one net became entangled in the survey boat’s propeller. The observations provide additional information on the spatial overlap between fishing activities and dolphin habitat and underscore the need to further assess potential interactions between fishing gears and marine mammals.

The information generated from the survey will contribute to science-based conservation strategies and fisheries management measures aimed at reducing risks to marine mammals while supporting sustainable fisheries. The initiative also strengthens collaborative monitoring among government agencies, conservation organizations, researchers, and local stakeholders toward improved protection of marine biodiversity in Malampaya Sound. ### (Koreen Bayani and Luz Romena)