Biodiversity conservation is one of the core goals of the Gulf of Mottama Project. In the Gulf of Mottama, the most famous species of conservation concern is the Critically Endangered Spoon-billed Sandpiper which migrates vast distances to overwinter on the rich mud flats here. It is an important symbol for the Gulf of Mottama and its mud flats.
Well, now we know that there are also exciting animals who can symbolize the importance of the gulf’s coastal waters! Since late 2018, researchers have confirmed the presence of three species of marine mammals in the Gulf of Mottama’s coastal waters: Indo-Pacific finless porpoise (Neophocaena phocaenoides), Irrawaddy dolphin (Orcaella brevirostris), and the Indo-Pacific humpback dolphin (Sousa chinensis). This research is ongoing, advised by me (thanks to my experience studying Irrawaddy dolphins in three other countries for my Ph.D.) as well as colleagues from different countries in Southeast Asia. The Myanmar Coastal Conservation Lab (MCCL), at Point B Design + Training at Mawlamyine University, is the main research team for the marine mammal research program, joined by students from Mawlamyine and Bago Universities.
Local fishers have known that dolphins and porpoises live in the Gulf, and the Department of Fisheries has responded to strandings of these animals. But, there had never been research surveys to scientifically document these animals in this area. In fact, it was the knowledge of local fishers that led to the beginning of this research program! While on a learning exchange trip in Chilika Lake, India, several Gulf of Mottama fishers and I were lucky enough to see the Irrawaddy dolphins that live there. These fishers were clearly accustomed to seeing animals like those dolphins – when asked, they confirmed: “Yes, we see these animals when we’re fishing in the Gulf of Mottama!”
This led to our research team interviewing people in coastal communities in Thaton, Paung, and Chaungzon, to learn from their “Local Ecological Knowledge” about the marine mammals that might be living in the Gulf of Mottama. From these people, we learned about the different types of marine mammals that they see. Several people told us that the number of these animals has decreased, and that they are sometimes accidentally caught in fishing gear.
This accidental capture is called “bycatch” and is a global threat to marine mammals. It is a very difficult problem to solve, because the fishers are usually not trying to catch the marine mammals – but they will need to change the way that they fish in order to avoid bycatch. Some communities consume the dead dolphins and porpoises, or use their oil because they believe it has medicinal properties. While it is possible that some people actively try to catch these animals, I believe that most of the capture is accidental – if fishers were trying to catch these animals, they would use different methods, and consumption of these animals would be much more common.
When dry season started in October 2018, we conducted our first boat-based surveys, working with a very skilled fisher and boatman from the village of Zee Gone, Chaungzon. In October, we had our first sightings of Indo-Pacific finless porpoises. In November, we had our first sightings of Irrawaddy dolphins. And, in February, our team was surprised to see Indo-Pacific humpback dolphins!
These three species can be found together in other parts of South and Southeast Asia. One of their preferred habitats is mixed fresh- and saltwater, so the Gulf of Mottama is a good habitat for them. Finless porpoises and Irrawaddy dolphins can live in freshwater or in the ocean.
Both the finless porpoise and Irrawaddy dolphin have flat faces, while the humpback dolphin has a long beak. In this region, humpback dolphins turn partially pink as they get older. The finless porpoise is the smallest and darkest of the three species; it also has no fin on its back, hence its name. It can be difficult to see in the water. we haven’t been able to get a photo of them yet! The Irrawaddy dolphin is Endangered on the IUCN Red List of Endangered Species, while the other two species are Vulnerable. For all three species, bycatch is a major threat.
To evaluate the status of these animals in the Gulf of Mottama, we will need to estimate how many individuals of each species live in this area. We also will need to estimate how many are killed by bycatch. This will allow us to assess whether bycatch is a serious threat to the Gulf of Mottama’s marine mammals. If it is, then work will need to be done with communities as well as the Department of Fisheries to develop ways to reduce this bycatch. Moving forward with conservation requires working closely with local communities to make sure that dolphin and porpoise conservation does not harm the livelihoods of local fishers. If the local communities are not included in this process, it is very unlikely that conservation efforts will succeed!
We will work to answer these and other research questions about these animals through 2019, and we hope into 2020 and beyond as well. We also know of a finless porpoise that was captured and released in a tributary of the Sittaung River about one year ago, so it is possible that there is at least one population of finless porpoises living in the Sittaung River. Dr. San Tha Tun, head of Marine Science at Mawlamyine University, and Dr. Tint Tun, one of Myanmar’s marine mammal experts with Marine Science Association of Myanmar, have told us about an accidentally captured finless porpoise on the edge of Mawlamyine, near the Attran River, several years ago. There is much more to explore and learn about marine mammals in the coastal and river waters of the Gulf of Mottama.
This is one of the few projects that have ever studied marine mammals on Myanmar’s coastline. It is likely that these animals are facing threats throughout the country’s waters, so our work on the Gulf of Mottama’s dolphins and porpoises is important not only for the Gulf of Mottama, but also for the national conservation. The most famous dolphins in Myanmar are of course the Irrawaddy dolphins in the Ayeyarwady River, but maybe our work can help make the Gulf of Mottama dolphins and porpoises famous, as well!