Southeast Asian Region

Southeast Asia encompasses twelve countries and part of both the Indian and Pacific Oceans. The marine features include shallow water habitat, such as mangroves, reefs, and estuaries. The Bay of Bengal dictates much of the region’s climate, especially during monsoon seasons. The region has annual monsoons, the Southwest and Northeast Monsoons, which impact temperature, salinity, and nutrient levels of the marine ecosystems. The monsoons also affect fishing effort in Southeast Asia, and severe inclement weather, such as the tsunami of 2004, can affect fisheries infrastructure by destroying boats, gear, and docks.

Fisheries in the region are diverse and vary by country. Artisanal and inshore fisheries are better documented than high seas fisheries, but generally information on the fisheries of individual countries is outdated or lacking. Gear types include gillnets, purse seines, trawls, driftnets, hook and line, and many others. Similar to many regions worldwide, gillnets, trawls, and purse seines are primarily responsible for bycatch of marine mammals and sea turtles in the Southeast Asia region. While some data are available on the number of vessels and gear types used, more information on their impact on bycatch rates is necessary to fully understand the bycatch problem in the region.

The region plays host to several species of seabirds (44), marine mammals (31), and sea turtles (6). Many of these are listed as endangered, critically endangered, or vulnerable on the IUCN Redlist. Notable marine mammals include those endemic to the region, such as the Indo-Pacific humpback dolphin; dwarf spinner dolphin; Irrawaddy dolphin; and a small form of Bryde’s whale, and those that are vulnerable or endangered like the dugong. Some seabird species in the region are vulnerable, though many are listed as “least concern” on the IUCN Redlist. All six species of sea turtle found in Southeast Asia are endangered or critically endangered.

Bycatch threatens many species in the region, particularly from gillnets, purse seines, and trawls. Bycatch is especially problematic for the dugong and the Irrawaddy dolphin, whose populations have severely declined and fragmented compared to populations 50 years ago. The dugong is locally extinct in many areas, and the Irrawaddy dolphin is believed to have as few as 60 individuals in some areas. Both animals are caught in gillnets in coastal waters. Sea turtles are commonly caught in gillnets, trawls, longlines, and driftnets. Green turtles, hawksbills, and olive ridley turtles are caught in several countries, namely Malaysia, Taiwan, and Vietnam. Seabird bycatch is less well-documented in Southeast Asia. In general, albatrosses and shearwaters are vulnerable to bycatch. However, not much is known about seabird bycatch. It is not currently perceived as a serious problem in the region.

Southeast Asia lacks fundamental bycatch mitigation efforts as a region; however, individual countries have taken initiative by passing legislation to promote sustainable fisheries and protect endangered species. Malaysia, India, and Bangladesh have enacted laws to protect turtles from direct take or egg collection. Additionally, many countries in the region have created fisheries management strategies, as well as protected areas. Despite their efforts, independent observer data and regional cooperation are necessary to move forward in reducing bycatch in the Southeast Asia region.