Presidential Letter to members of the Government of the Philippines concerning the impacts of development on critically endangered Irrawaddy Dolphins

17 October 2020


Secretary of the Department of Public Works and Highways

Bonifacio Drive, Port Area

Metro Manila, Philippines


Dear Secretary Villar,

As President of the Society for Marine Mammalogy, I write to express concern about the potential for the proposed Panay-Guimaras-Negros (PGN) Bridges Project to threaten the survival of a Critically Endangered population of Irrawaddy dolphins (Orcaella brevirostris) that resides in this region.[1] The Society for Marine Mammalogy is the world’s largest professional group dedicated to the study of marine mammals, with a membership of approximately 2,000 scientists from more than 35 countries. Our goal is to facilitate the understanding and conservation of marine mammals and the ecosystems that support them.

The Irrawaddy dolphin population in the Iloilo-Guimaras Straits is extremely small, with roughly 10-30 remaining individuals. The population’s core habitat is limited to the Pulupandan-Bago estuary and coastal waters of Buenavista. These dolphins are integral to the lives of fishermen in Iloilo, Guimaras, and Negros, who use the dolphins’ occurrence to indicate the locations of concentrations of fish and shrimp. The Iloilo-Guimaras Straits Irrawaddy dolphin population is one of only three known Philippine populations of this globally Endangered species (red-listed by the IUCN), each of them isolated from the others. The other two Philippine populations are in Malampaya Sound, Palawan (also red-listed by IUCN as Critically Endangered) and in coastal waters of Quezon.

Studies led by Philippine scientists indicate that the Pulupandan-Bago (on Negros) and Buenavista (on Guimaras) areas support relatively high densities of dolphins; the animals use these areas for feeding, nursing their young, and resting. I am concerned that the proposed construction at the entrances and exits of these bridges will damage and degrade vital habitat of these critically endangered dolphins and therefore I encourage you to construct the bridge outside habitat critical to the dolphins.

Ensuring that Irrawaddy dolphins survive in the Iloilo-Guimaras Straits will not only contribute to the conservation of global biodiversity, but will also help to preserve the natural heritage of the Ilonggo people.

Thank you for your kind attention to this matter. We would be pleased to offer our Society’s mmbers’ expertise should you need advice on the dolphin’s biology that will aide in locating the bridge to preserve dolphin critical habitat.


Charles Littnan

President, The Society for Marine Mammalogy


Here is a link to the letter that was sent.

Here is a link to a similar letter submitted by the IUCN.

More information on the status of the Irrawaddy Dolphin can be found here.


Additional Information on the PNG Bridges Projects:

There are two bridges that have been approved to connect the Islands of Panay, Guimaras, and Negros.

Bridge 1 – connecting Panay Island and Guimaras.  One of this bridge’s entrance/exit will be in Buenavista (Guimaras) and within Irrawaddy dolphin habitat. Construction is scheduled to start in 2021.





Bridge 2 – connecting Guimaras Island and Negros Island.  This touches the Pulupandan area of Irrawaddy habitat. This project was also supposed to start in 2021 but is being postponed for now because of an ongoing feasibility study.



The feasibility study done by the Chinese Highway Consulting firm on the engineering side has been completed and accepted by the Philippine government . For Bridge 2, it recommends the Pulupandan site to be the best site (