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My Geography 899 Mekong (Irrawaddy) Dolphins Annotated Bibliography Andersen, M., Knize, C. C. 1999. Annotated checklist and identification key to the whales, dolphins, and porpoises (order cetacean) of Thailand and adjacent waters. Natural History Bulletin of the Siam Society 47: 27-62 Aragones, L. V., Jefferson, T. A., Marsh, H. 1997. Marine mammal survey techniques applicable in developing countries. Asian Marine Biology 14: 15-39 Interview survey, land-based survey, ship/boat survey, aircraft survey, and carcass analysis techniques are explained in the article. Interview survey would be the most appropriate technique to use in the Laos and Cambodia. The authors clearly explain each technique such as method, requirement, and survey output with examples of data sheets and figures. Baird, I. G., Mounsouphom, B. 1997. Distribution, mortality, diet and conservation of Irrawaddy dolphins (Orcaella brevirostris) in Lao PDR. Asian Marine Biology 14: 41-48. The article seems to be the latest update research on the dolphins in the Mekong. It tells a lot of information especially on distribution and threats to the population of the dolphins in the Mekong River. The discussion on conservation strategies brought me many research questions. Many information based on the survey in 1991. Distribution: In Laos, dolphins live in two main areas, below Khone Falls and Sekong River, a tributary of the Mekong River. Waterfalls in the mainstream and the tributaries are the natural barriers for upstream movement of the dolphins. Traditional perception: Dolphins have long been respected by the local. They believe that dolphin are reincarnated people. (p. 45) Mortality: According to the research the main cause of the mortality is fishing activities. Behavior: Movement and the decline of the dolphin might be related to its food supply. Conservation strategies: There are many threats to the dolphin, decrease in food supply, proposed dams, explosives, and gillnets. The authors also give a good comment on strategies to conserve the dolphin, "Dolphin conservation strategies should involve local people in all parts of the planning and implementation process and should consider the entire river ecosystem rather than taking a single species.(p. 41)" "The days of single-species conservation strategies are coming to an end as a result of the realisation that ecosystem conservation and management models are more likely to provide a broader perspective and more answer to the problems faced. What is required are partnerships with which bring researchers and local people together. (p.47) Baird, I. G. 1991. Preliminary surveys of Irrawaddy dolphins (Orcaella brevirostris) in Lao PDR. Earth Island Institute and the Whale and Dolphin Conservation Society. It might be the first survey on the Mekong dolphin. Ian took one week on his survey from December 7 to 15, 1991. The survey attempted to gather as much information as possible about the dolphin. Three main studied aspects are the range, attitude towards dolphin, and threats of the dolphin. Good information on its behavior that will be important for my field work. The research did not give much direct information in northeastern Cambodia but the information could be applied, because the two areas are very close. Range of the dolphin in Laos: After sighting and receiving oral reports, they believe that the two major habitats are below Leepee waterfall and Sekong river(p.1). A significant population of the dolphin is located in a "deep water pool" or "wang" (Lao language) (p. 2) They can be seen easiest in the early morning and late afternoon (p.3). "It seem likely that the dolphins rely on these migrating schools of fish as a food supply. However, much more knowledge about these cycles is needed.(p.7)" According to the sentence, food supply are one of the most important factor for the dolphins. Fisheries management and studies on this topic is needed. To save the dolphins we need to save the whole system. Attitude towards dolphin: Lao people also widely believe that dolphins are "the friends of people" (p.3). According to Lao fairy-tale the dolphin (Pa Ka) were a wife of a river tern.(p.4) The local perspective and attitude toward the dolphin in southern Lao might be very close to northern Cambodia. Studies on this topic is needed more for the dolphin conservation strategies. Without participation from locals we can not save the dolphin. Threats: Shooting, hand gernades, and dynamite use are direct threats to the dolphin, even though those methods are banned in Lao. "But bomb is still widely practiced in Kumpuchea(p.8)" "A story in a Vientiane newspaper printed in November, 1991 stated that two people were sent to jail for shooting a dolphin earlier in the year.(p.7)" The most serious threat is mono-filament nylon gillnets, which were brought to Lao 20 years ago. "Ultimately, the most insidious threat to the long-term survival of the dolphin in Lao PDR is the continued deterioration of the river ecosystem, including fish stocks.( p.10)" Suggestion: The researcher suggested many future research questions, which some of them might be already studied later after this research; What species of fish do they prefer?, How many are there?, Do they migrate?, Are they genetically different from the Irrawaddy dolphins in the Gulf of Thailand and the South China Sea?, What are their mating patterns in the wild?, other suggestions are: - Local communities should not be ignored. - Sustainable fishery management must be practiced - The relationship between the dolphin and other species of wildlife should be investigated. - The relationship between the dolphin and human should be investigated in more detail. - Any move to develop Hangkorn area, where the dolphin can be seen easily, must be taken with great care. - Information exchange between locals and outsiders should be considered. Baird, I. G., Mounsouphom, B. 1993. Lao community fisheries and dolphin project progress report #1. The report tells very clear information and situation. The explosive fishing in Cambodia was discussed a lot. The project try to solve this problem by both local and international levels but it could not work well. Workshops were held many times in the areas. The locals in the area seemed to cooperated very well. Opinions of the villagers is the key of the project. There seem to be conflict between locals Laos and Cambodian explosive fisher. " They feel powerless to stop the explosive fishing from happening close to their homes and are fearful of getting shot y Cambodians ...(5.)" Soldiers in the areas are also the cause of using explosives. "... partly because Hun Sen soldiers in the area had not received their salaries for a long time,... (p.6)" "Many villagers asked the project staff and government to negotiate with the Cambodians to stop explosive fishing near the border (p.4)" The fishing community network in Cambodia side and between the two countries is needed to be set up. Baird. I. G. 1994. Conservation and the community: joining forces to save the Irrawaddy dolphin. Sonar. 11: 24-25 Good summary of the project in Laos. " ... when water levels are low. This stretch of the Mekong River also act as the border between Laos and Cambodia." Baird, I. G., Mounsouphom, B. 1994. Irrawaddy dolphins (Orcaella brevirostris) in southern Lao PDR and northeastern Cambodia. Natural History Bulletin of the Siam Society 42: 159-75 Information about the dolphin in Cambodia, feeding and seasonal migratory behavior was studied more in detail from the preliminary surveys in 1991. This research is based on survey and work during 1991 to 1993, the survey in Cambodia was done in 1993. The main techniques are animal sighting and locals interviewing. Genetic studies was conducted in this research by collecting samples from dead animals. Distribution: In Lao, villagers reported that found a group of dolphins upstream of the Khone fall during high-water season. In Cambodia, the most concentrate area found the dolphins are in Kratie and Strung Treng provinces. It is sometimes seen in Ton Le Sap. Information about the distribution in Cambodia is based only on oral report not from sighting. "Villagers identified five deep water pool areas in an approximately 200-km section of the Mekong River between Kratie and Strung Treng/ Lao border where dolphins are said to live in considerable numbers on a regular basis. (p. 162)" Local perception: Local people in Cambodia have the same attitude as Lao people do as it was reported in the 1991 research. Legal status: In Laos, the dolphins are fully protected by law, it's illegal to hunt, capture, and trade, but not in Cambodia. Behavior: "It is appears that the dolphins tend to move around the deep pool area within an area less than 1 km long and 0.5 km or less wide ...(p. 164)" Pool are approximately 10-30 meters deep. Feeding: The dolphins feed on scaled and non-scaled fish, from small to large species, which some of them are over a meter long. They like to eat only lower part of large species, because of hard head, dorsal, and pectoral spines. Those leftovers which usually found in the deep pool area were sometimes eaten by villagers if they are still fresh. Feeding and praying behavior should be studied more in detail, especially in local knowledge. Births: Villagers report that dolphins are born in dry season, April or May. Threats: Arial bombing by American and shooting by soldiers in the Indochina War are the worst threats in the pass, that cause a lot of decline in the population. The serious threats today are explosive and gillnets. Bomb fishing were heavily used in the pass and it is still practiced in some areas. It not only kill dolphins but also the fish in the Mekong River, which the dolphins depend upon. Even though villagers don't want them to die, in some cases they have to let them die because they are so poor that can not afford the damage of the net. Food supply is one of the most serious threats, according to villagers fish catch has declined 20-25 % per year. Sustainable fishery management with locals participation will be the good strategies to save the dolphins and the system. Loa Community Fisheries and Dolphin Protection Project should be studied about the advantages and disadvantages, it might be applied in northeastern Cambodia. Planed dams on the Mekong mainstream and Sekong River will cause serious impacts to the dolphins and fish population. The planed dam on the mainstream at Strung Treng and Sambor, Cambodia, would be the most serious one. None of study have been done.!!!! Interesting !!! Baird, I. G. 1992. New campaign to save dolphins in Laos. Earth Island Journal. p.7 Carwardine, M. 2000. Dorling Kindersley Handbook of Whales dolphins and porpoises. Dorling. London. Freeland, W. J., Bayliss, P. 1989. The Irrawaddy river dolphin (Orcaella brevirostris) in coastal waters of the northern territory, Australia: distribution, abundance and seasonal changes. Mammalia. pp. 49-57 Hill, M. T. 1995. Fisheries ecology of the lower Mekong River: Myanmar to Tonle Sap river. Natural History Bulletin of the Siam Society 43: 263-288 Leatherwood, S., Reeves, R.R. 1994. River dolphins: a review of activities and plans of the Cetacean Specialist group. Aquatic Mammals. 20.3: 137-154 Osborne, M. 2001. Mekong. Allen &Unwin. Australia. Perrin, W.F., Dolar, M.L.L. Alava, M.N.R. 1996. Report of the Workshop on the Biology and Conservation of Small Cetaceans and Dugongs of Southeast Asia. UNEP(W)/EASWG. 1/2. 101pp. Roberts, T. R., Baird, I. G. 1995. Traditional fisheries and fish ecology on the Mekong river at Khone waterfalls in southern Laos. Natural History Bulletin of the Siam Society 43: 219-262 Roberts, T. R. 1995. Mekong mainstream hydropower dams: run-of-the-river or ruin-of-the-river?. Natural History Bulletin of the Siam Society 43: 9-19 Smith, B. D., et. al. eds. 2002. Handbook for an intensive training course on marine mammal research techniques for scientists in South and Southeast Asia. Wildlife Conservation Society. Stacey, P. J., Leatherwood, S. 1997. The Irrawaddy dolphin, Orcaella brevirostris: a summary of current knowledge and recommendations for conservation action. Asian Marine Biology 14: 195-214 Great information about Irrawaddy dolphin in all aspects. The map, Fig. 1, shows latest distribution information of the dolphins. Almost all of new information regarding to the Mekong dolphin is based on Stacey's thesis in 1996, some is from Perrin 1996. Distribution: There isn't new information about distribution in Loa and Cambodia, almost all information is based all Baird research in between 1991 to 1994. "Their status in coastal wasters (in Cambodia) is unknown.(p. 198)" "All location of Irrawaddy dolphin records are connected by a continuous band of water less than 200 m deep ...(p. 200)" Habitat: The Irrawaddy dolphins are frequency seen in shallow water. In Lao, the depth of a deep pool where they are often seen was measured. Stock identification: No information has confirmed that there is a species distinct. Behavior: Many information on behavior was referred from Stacey's research in 1996. Interesting information about behavior such as group size, interactive with people, feeding, and some other behavior. Group size: small group size, about 1.63 to 3.4, according to the available reports. (p. 202) Overall people hold the Irrawaddy dolphins in high regard. Feeding: in Myanmar, fishermen report that catfish were the primary food for the dolphins. Threats: New fact about threat to the Irrawaddy dolphins is that live-capture for display. "Eight Irrawaddy dolphins caught during net fishery operations in late 1994 were removed from coastal waters of Cambodia and transported to Safari World in Thailand (Leatherwood unpubl. data) (p. 205)" Other interesting information is that " There are no documented cases in which Irrawaddy dolphins have been affected by dams or barrages, but plans to construct hydro-electric dams in Laos and Cambodia could fragment populations and affect their habitats and food supplies. (p. 205)" Protection measures: Cultural, protected areas, legal status, captive breeding, education, and tourism measures were discussed in this article. The most interesting measure is education and community involvement. "Education and community involvement could be the most important routes to succeeding with Irrawaddy dolphins conservation.(p. 207)" The author mentioned about The Community Fisheries and Dolphin Protection Project in Laos as a good example for this. Mekong River system is one of seven main areas of Irrawaddy dolphin concentration suggested by the author. Recommendation: Some of interesting recommendations build on outlined in the IUCN/SSC Action Plans are: 1. Monitor the abundance of Irrawaddy dolphins in the seven identified areas of concentration. 2. Efforts should be made to obtain further information about Irrawaddy dolphins. 3. Given the pressure on, and resulting status of, river dolphins world-wide, Irrawaddy dolphins living in riverine and estuarine habitats should be given special consideration. Pollution, dams, vessel traffic and fishing nets could quickly spell disaster for dolphins in these very susceptible environments. 4. Protected areas should be established with as much involvement by local people as possible and designed with features to maximize their social and economic benefits. 5. It remains important to gather further information on Irrawaddy dolphin biology and ecology, and to monitor the animals' response to local human activities and developments. 6. Research should investigate the possible existence of genetically distinct stocks, especially between marine and freshwater populations. 7. Conservation programmes should seek to provide financial, logistical and/or social support, as needed, to local people. Stacey, P.J.* and G.T. Hvenegaard. 2002. Habitat use and behaviour of Irrawaddy Dolphins (_Orcaella brevirostris_) in the Mekong River of Laos. Aquatic Mammals 28(1):1-13. Stacey, P. J. 1996. Natural history and conservation of Irrawaddy dolphins, Orcaella brevirostris, with special reference to the Mekong River, Lao PDR. x + 123 pp. M.Sc. thesis, University of Victoria, Canada. Thein, U. T. 1997. The Burmese freshwater dolphin. Mammalia. pp.233-234 Online ABC NEWS. 2001. Dolphins Dying in the Mekong. (On-line) http://abcnews.go.com/sections/science/DailyNews/dolphins990604.html (September 27, 2001). " 'You save the Mekong River dolphin and you save the Mekong as a whole' says Baird." The author said that no survey in Cambodia's river before Baird did in 1997. (Check) Check more detail on Phong Choeun as it was mentioned to be a Laos replicated project in Cambodia. Feature Magazine.2000. This 9 page article gives excellent and reliable information in all aspects about the Irrawaddy dolphins in the Mekong River and the project. The Laos Community Fisheries and Dolphin Project was set up in 1993 and closed in 1999 because of stop funding from EU. According to the article there were eighteen dolphins died during 1990 - 1995. (Check, another resource says during Dec 1990 to May 1993.) There are about 300 animals left in the world, and almost half of that is in the Mekong River. (Check) There were about 1,000 animals killed by soldiers during Cambodia civil war. Oneworld.net. 2001. Spirit trap: The Mekong. (On-line) http://www.oneworld.org/ni/issue273/delta.htm (October 3, 2001). The author, a Canadian who work with TERRA, is one of reliable sources. There are some part of the article that mentioned about the cause of decline of fish in the Mekong River and the threat to the dolphin. "... and a more rapid decline within the last four years. They believe it may have to do with the introduction of modern fishing gear and the growing market for wild Mekong fish" "In the past we never fished the deepwater pools because we were afraid to disturb the spirit." " 'How can they think of touching Hoo Sahong - it is one of two most important channels for fish moving upstream!' exclaimed one man, surrounded by children and fishing gear. 'if they harm hte fish, we will die' says one woman with a baby in her lap. 'Everyone here depends on fish.' A woman standing nearby adds: 'We have nothing but the river.' " University of Michigan. 1997. Irrawaddy Dolphin. (On-line) http://animaldiversity.ummz.umich.edu/accounts/orcaella/o._brevirostris.html (April 14, 2002) 1uptravel.com. Map of Indochina Ethnolinguistic Groups. (On-line) http://www.1uptravel.com/worldmaps/cambodia5.html (April 7, 2002) The Christian Science Monitor. Saving freshwater dolphins means saving their rivers.1999. (On-line) http://www.csmonitor.com/durable/1999/06/03/p8s2.htm (April 14, 2002) IUCN. 2001. Occasional Paper No. 23 Biology and Conservation of Asian River Cetaceans. (On-line) http://www.iucn.org/themes/ssc/pubs/rivercetacean.htm (October 3, 2001). Environmental Investigation Agency. 1998. A Review of the Impact of Anthropogenic Noise on Cetaceans. (On-line) http://www.eia-international.org/Campaigns/Cetaceans/Briefings/noise.html (April 14, 2002) Jim's Vietnam Vet Homepage. 2001. Map of South East Asia. (Online) http://www.nexus.net/~911gfx/sea-ao.html (April 5, 2002) Phnom Penh Daily. Experts say Mekong River Dolphin will extinct. (On-line) http://www.phnompenhdaily.com/01-04-99.htm (March 2, 2002) The author mentioned about two experts who went to study the dolphins from Australia and Japan, they might be a good source for information. The author also mentioned about Dr. Touch Seang Tana as a Cambodian specialist on dolphins, and other Cambodian officials. Tourism to see the dolphins is another main point. It might be an important aspect to be studied. "Cambodia's Ministry of Tourism, targeting to set up a new tourist destination besides the unique historical temple of Angkor Wat in Siem Reap province." "About 17 kilometers south of Kratie town, known as Prek Kampi village where about a half dozen dolphins spend afternoons hunting and playing about 10 meters offshore." " Local villagers are waiting to bring visitors by riverboats to see those dolphins with 10 meters distant from them. It costs about 10,000 riels ($2.63) for a few hours." Needed Borsani, J. F., et. al. 2001. The acoustic environment and behavior of some Irrawaddy dolphins, Orcaella brevirostris (Owen in Gray, 1866) of the lower Mekong river basin. 14th Biennial Conference on the Biology of Marine Mammals. p.30 The visual-acoustic survey estimated nine dolphins in a deep water pool South of Khone Falls. Conservation Planning Guide Book etc. Poulsen, A. F., Valbo-Jorgensen, J. 2001. Deep Pools in the Mekong River. Catch & Culture. Vol. 7, No.1. Baird, I.G., Mounsouphom, B. and Stacey, P.J. 1994. Preliminary surveys of Irrawaddy dolphins (Orcaella brevirostris) in Lao PDR and northeastern Cambodia. Reports of the International Whaling Commission 44: 367-69 |