Irrawaddy Dolphin:
Threats and Legal Protection

October 27, 2021Lu Shegay


The Irrawaddy dolphin is a euryhaline species of oceanic dolphin found in discontinuous subpopulations near sea coasts and in estuaries and rivers in parts of the Bay of Bengal and Southeast Asia. This species closely resembles the Australian snubfin dolphin and was not presented as a separate species until 2005. Although found in much of the riverine and marine zones of South and Southeast Asia, the only concentrated lagoon populations are found in Chilika Lake in Odisha, India, and Songkhla Lake in southern Thailand.

"Irrawaddy Dolphin (Orcaella brevirostris) surfacing near boat" by berniedup is licensed under CC BY-SA 2.0


Many species of aquatic animals are threatened by a number of factors, which are mainly caused by anthropogenic activities. These include, first of all, fishing activities, due to which not only targeted animals die but also those who are caught accidentally because of nets wandering in the oceans. Other threats include plastic pollution, ship strikes, oil spills, wildlife trafficking, etc.

As for the Irrawaddy dolphin, they are most susceptible to human conflict compared to other dolphins that live farther and deeper in the ocean. Drowning in gillnets is a major threat to them throughout their range. During 1995-2001, it was reported that 38 dolphins died and 74% died as a result of entanglement in gillnets with large mesh sizes. The majority of those individuals died because of bycatch, accidental capture, drowned in gillnets and dragnets, and in bottom-set crab nets in the Philippines. In Myanmar, another range country, these animals are threatened by electrofishing, gold mining, and dam building - these threats remain continuous at present times as well.

Areas, where fishing activities are common, are subject to a lot of alterations of significant relevance to the functioning of the entire marine ecosystem. Targeted fisheries reduce the abundance of species, affect the overall population of aquatic animals modifying age and size structure, sex ratio, genetics, and species composition of the targeted species, as well as of their associated and dependent species. Fishing also affects ecological processes at a very large and significant scale.

“The alteration of the habitat by various human activities may be physical (e.g. by adding artificial structures like artificial reefs, oil rigs, aquaculture installations), mechanical (e.g. through the "ploughing" effect of dredges and trawls), or chemical (e.g. through injection of nutrients, pesticides, heavy metals, drugs, hormones). Some aspects of fisheries can have significant and long-lasting effects, e.g. destructive fishing techniques using dynamite or cyanides or inadequate fishing practices (e.g. trawling in the wrong habitat); pollution from fish processing plants; use of ozone-depleting refrigerants; dumping at sea of plastic debris that can entangle marine animals or be swallowed by turtles; loss of fishing gear, possibly leading to ghost fishing; lack of selectivity, affecting associated and dependent species, resulting in wasteful discarding practices, juvenile mortality, added threat to endangered species, etc. Poorly-managed large-scale mariculture can damage coastal wetlands and nearshore ecosystems, often used as nurseries by key capture fishery resources, and contribute to ecosystem contamination with food residues, waste, antibiotics, hormones, diseases, and alien species.”

The presence of legal regulations, unfortunately, is not sufficient for protecting these animals. Catching these dolphins supply the local communities as the main means of survival. Moreover, in several Asian countries, Irrawaddy dolphins are captured and trained for performance in public aquariums and entertainment purposes. Their unique behavior, which includes spitting water, spy-hopping, and fluke-slapping makes them popular for dolphinarium shows. The primary reason for using this species in dolphinariums is because of their ability to live in freshwater tanks and the high cost of marine aquariums systems is avoided. Sadly, these dolphinariums have a high demand in the public. Furthermore, some other tourist activities are increasing in Asia, such as large numbers of boats circulating in the areas where these dolphins live, which puts a large strain on these dolphins.

"File:Irrawaddy dolphin-Orcaella brevirostris by 2eight.jpg" by Stefan Brending (2eight) is licensed under CC BY-SA 3.0

Legal Protection and Conservation Efforts

The Irrawaddy dolphin is classified as Endangered, and the IUCN Red List includes 5 subpopulations as endangered out of 7. Entanglement in fishnets and habitat degradation now remain the leading issues in the conservation of these animals. Some Irrawaddy dolphin populations are classified by the IUCN as Critically Endangered, in Laos, Cambodia, Vietnam (Mekong River sub-population), Indonesia (Mahakam River sub-population, Borneo), Myanmar (Ayeyarwady/Irrawaddy River sub-population), the Philippines (Malampaya Sound sub-population), and Thailand (Songkhla Lake sub-population).

At the international level, CITES, an international legal instrument aimed at the regulation of international trade, protects the species and includes them in Appendix I, supposedly the highest and strict protection for those animals listed there. Under Appendix I, the commercial trade of listed species is not prohibited and allowed only in exceptional circumstances and with a special permit. However, the enforcement depends on individual countries, i.e, range countries, and trade of this species, particularly, sale of these animals to dolphinariums is not the major issue presently. Initially, the Irrawaddy dolphin was listed in Appendix II but was moved to Appendix I in 2004.

​​The Convention on the Conservation of Migratory Species of Wild Animals or the Bonn Convention (CMS) is an international agreement that aims to conserve migratory species throughout their ranges. Under CMS, the Irrawaddy dolphin is listed under both Appendices I and II. The reason for being included in Appendix I is due to this species being categorized as species in danger of extinction throughout all or significant areas of their range countries. Listing under Appendix II gives this species the protection in a way that CMS Parties shall strive towards strictly protecting these animals, conserving or restoring the places where they live, mitigating obstacles to migration, and controlling other factors that might endanger them, as well as having an unfavorable conservation status. The Irrawaddy dolphin is also covered by the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region.

The CMS also has the Action Plan for the species, and the Irrawaddy dolphin is not an exception. Under the Action Plan for the Conservation of Freshwater Populations of Irrawaddy Dolphins provides some detailed information on strategies for mitigating bycatch:

At the national level, in some countries, a portion of Irrawaddy dolphins was placed in wildlife sanctuaries. In Cambodia, Fisheries Law protects these animals and lists them as endangered species. In 2005, WWF established the Cambodian Mekong Dolphin Conservation Project supported by the government and local communities, the aim of which was to support the survival of remaining populations of Irrawaddy dolphins through research and education. In 2012, the government of Cambodia announced a 180-km-long (110 mi) stretch of the Mekong River from eastern Kratie province to the border with Laos as a limit fishing zone, where floating houses, fishing cages, and gill nets are not allowed, except for simple fishing. This area is patrolled by a group of river guards, specifically to protect dolphins.

India protects the Irrawaddy dolphin in its Schedule I of the Wildlife Protect Act, which bans their killing, transportation, and sale of body parts.

A conservation program “Conservation Foundation for the Protection of Rare Aquatic Species of Indonesia” was launched, which was focused on the protection of the population of these animals and their habitat. This program does not only educate the public but also provides monitoring of the population of these dolphins and the status of their habitat.

In 2005, the Department of Fisheries in Myanmar established a protected region of 74 km (46 mi) for the Ayeyarwady River between Mingun and Kyaukmyaung and issued a number of provisions for the protection of this species. This includes “a mandatory release of entanglement dolphins, prohibition of the catching or killing of dolphins and trade in these animals or their body parts, and the prohibition of electrofishing and gillnets more than 91 m (300 ft) long, or spaced less than 180 m (600 ft) apart.”

Read more: Catch Composition and Conservation Management of a Human–Dolphin Cooperative Cast-Net Fishery in the Ayeyarwady River, Myanmar

In 2008, the Department of Forestry and Sarawak Forestry Cooperative in Sarawak, Malaysia, also established a protected area for the Irrawaddy dolphin, which included the prohibition of catching or killing of dolphins and trade in them and their body parts, as well as the prohibition of the use of gillnets.

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