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Journal of Ethology

, Volume 36, Issue 2, pp 169–180 | Cite as

Factors influencing the behaviour of Irrawaddy dolphins Orcaella brevirostris (Owen in Gray, 1866) in Brunei Bay, Malaysia

  • Anisul Islam Mahmud
  • Saifullah Arifin Jaaman
  • Azmi Marzuki Muda
  • Hairul Masrini Muhamad
  • Xuelei Zhang
  • Felicita Scapini
Article

Abstract

The population of Irrawaddy dolphins in Brunei Bay, Malaysia is little studied. This study aimed at contributing information on how abiotic and other factors influence different aspects of their behaviour displayed at the water surface. Several behaviours, i.e. foraging, travelling, foraging behind trawler, milling and socializing were observed during boat-based line transect surveys (2013–2016). The behaviours of individuals and groups were filmed or noted, and the abiotic factors of the habitat were registered at the same time. The number of “travelling” individuals was negatively correlated with surface water salinity (p value = 0.04) and positively correlated with turbidity (p value = 0.01). Fisher’s exact test also revealed that the behaviours of dolphin groups significantly differed with the ranges of several abiotic factors, i.e. foraging behind trawler with depth (p value = 0.001), travelling with surface water salinity (p value = 0.05), travelling and foraging behind trawler with turbidity (p value = 0.04, 0.01). The results for foraging behind trawler differed significantly between the groups with calves and those without calves (χ2 test, p value = 0.04), where groups with calves were less likely to forage behind trawlers. Significant differences were observed among group sizes for travelling, milling and socializing (χ2 test, p value < 0.05), with large groups (11–20 individuals) more frequently foraging, milling and socializing, compared to smaller ones. The current study is the first behavioural observation for Irrawaddy dolphins in Brunei Bay and these findings will help researchers, conservationists, local marine park managers and policy makers in developing effective conservation and management plans for the area.

Keywords

Irrawaddy dolphin Behaviour Abiotic factors Group size Brunei Bay 

Notes

Acknowledgements

The authors would like to give special thanks to the team of the Marine Endangered Species (MES) Program, INOS-UMT for the database. The corresponding author would also like to acknowledge the European Commission for providing a scholarship (2014–2016) under the Erasmus Mundus Masters Course in Tropical Biodiversity and Ecosystems (TROPIMUNDO). Thanks to Eléonore R. A. Viez (BEVT, ULB) for helping in data analysis, and Miro Kolenic for language revision. Also thanks to Mr. Ismail (boatman) and his family members for cooking for us during the survey periods. Authors give thanks to the Sarawak Forestry Department for giving permission to conduct research on biological resources in Sarawak waters [Permit No. NCCD.907.4.4(JLD.11)-35]. Thanks to three anonymous reviewers for their comments for improving the manuscript.

Funding

The study was funded by the Ministry of Education (MOE) Malaysia, Higher Institution Centre of Excellence (HICOE) Grant Scheme (2013–2015) of INOS-UMT; FIO-UMT surveys for marine mammals and sea turtles in the bay of Brunei, 2015–2018 project and the China-ASEAN maritime cooperation fund.

Compliance with ethical standards

Conflict of interest

The authors of different universities originally produced this research article, and there is no overlap with other articles published or in press in journals, books or conference proceedings, or in preparation, and all co-authors agreed to submit to this journal. Thanks to three anonymous reviewers for their valuable comments for improving the manuscript. The authors declare that they have no conflict of interest.

References

  1. Ahmad-Kamil EI, Ramli R, Jaaman SA, Bali J, Al-Obaidi JR (2013) The effects of water parameters on monthly seagrass percentage cover in Lawas, East Malaysia. Sci World J 2013:1–8CrossRefGoogle Scholar
  2. Allen SJ, Pollock KH, Bouchet PJ, Kobryn HT, McElligott DB, Nicholson KE, Smith JN, Loneragan NR (2017) Preliminary estimates of the abundance and fidelity of dolphins associating with a demersal trawl fishery. Sci Rep 7:4995CrossRefPubMedPubMedCentralGoogle Scholar
  3. Annandale N (1915) Fauna of the Chilka Lake: mammals, reptiles and batrachians. Mem Indian Mus 5:165–174Google Scholar
  4. Baird IG, Mounsouphom B (1994) Irrawaddy dolphins in Southern Lao PDR and Northeastern Cambodia. Nat Hist Bull Siam Soc 42:159–175Google Scholar
  5. Baird IG, Mounsouphom B (1997) Distribution, mortality, diet and conservation of Irrawaddy dolphins (Orcaella brevirostris Gray) in Lao PDR. In: Morton B, Perrin WF (eds) Asian marine biology. Hong Kong University Press, Hong Kong, pp 41–48Google Scholar
  6. Bali J, Jaaman SA, Tisen OB, Landong WS, Zaini MK, Yee CW, Bakir K, Saimin S (2008) Aerial sighting rate of marine life in Sarawak waters. In: 7th International Scientific Symposium of the Intergovernmental Oceanographic Commission -Western Pacific (IOC/WESPACT), Kota Kinabalu, Sabah, pp 1–13Google Scholar
  7. Baumgartner MF, Mate BR (2005) Summer and fall habitat of North Atlantic right whales (Eubalaena glacialis) inferred from satellite telemetry. Can J Fish Aquat Sci 62:527–543CrossRefGoogle Scholar
  8. Beasley I, Pollock K, Jefferson TA, Arnold P, Morse L, Yim S, Lor Lim S, Marsh H (2013) Likely future extirpation of another Asian river dolphin: the critically endangered population of the Irrawaddy dolphin in the Mekong River is small and declining. Mar Mamm Sci 29:226–252CrossRefGoogle Scholar
  9. Broadhurst MK (1998) Bottlenose dolphins, Tursiops truncatus, removing bycatch from prawn trawl codends during fishing in New South Wales, Australia. Mar Fish Rev 60:9–14Google Scholar
  10. Bujang JS, Zakaria MH, Arshad A (2006) Distribution and significance of seagrass ecosystems in Malaysia. Aquat Ecosyst Health Manag 9:203–214CrossRefGoogle Scholar
  11. Corkeron PJ, Bryden MM, Hedstrom KE (1990) Feeding by bottlenose dolphins in association with trawling operations in Moreton Bay, Australia. In: Leatherwood S, Reeves RR (eds) The bottlenose dolphin. Academic Press, San Diego, pp 329–336CrossRefGoogle Scholar
  12. Daisy Kaplan J, Connor RC (2007) A preliminary examination of sex differences in tactile interactions among juvenile Atlantic spotted dolphins (Stenella frontalis). Mar Mamm Sci 23:943–953CrossRefGoogle Scholar
  13. Daura-Jorge FG, Wedekin LL, Piacentini VDQ, Simões-Lopes PC (2005) Seasonal and daily patterns of group size, cohesion and activity of the estuarine dolphin, Sotalia guianensis (PJ van Bénéden)(Cetacea, Delphinidae), in Southern Brazil. Revista Brasileira de Zoologia 22:1014–1021CrossRefGoogle Scholar
  14. Department of Fisheries Sabah (2010) Summary of annual fisheries statistics Sabah 2008. Kota Kinabalu, Malaysia. http://www.fishdept.sabah.gov.my/?q=en/download/466 Accessed 4 Apr 2016
  15. Dolar MLL, Perrin WF, Yaptinchay AASP, Jaaman SA, Santos MD, Suliansa MAM (1997) Preliminary investigation of marine mammal distribution, abundance, and interactions with humans in the Southern Sulu Sea. In: Morton B, Perrin WF (eds) Asian marine biology. Hong Kong University Press, Hong Kong, pp 61–81Google Scholar
  16. Dolar MLL, Perrin WF, Gaudiano JO, Yaptinchay AASP, Tan JML (2002) Preliminary report on a small estuarine population of Irrawaddy dolphins Orcaella brevirostris in the Philippines. Raffles Bull Zool Suppl 50(Supplement):155–160Google Scholar
  17. Dudzinski KM (1998) Contact behavior and signal exchange in Atlantic spotted dolphins (Stenella frontalis). Aquat Mamm 24:129–142Google Scholar
  18. Eng LP (1992) Water quality in the coastal areas of Brunei Darussalam: status, management issues and recommendations. In: Silvestre G, Matdanan HJH, Sharifuddin PHY, De Silva MWRN, Chua TE (eds) The coastal resources of Brunei Darussalam: status, utilization, and management. WorldFish, Malaysia, pp 91–108Google Scholar
  19. ESRI (1996) ArcView spatial analyst: advanced spatial analysis using raster and vector data. California: Environmental Systems Research Institute. http://library.duke.edu/data/collections/gis/esri/esri_1996. Accessed 6 Apr 2016
  20. Fertl D, Leatherwood S (1997) Cetacean interactions with trawls: a preliminary review. J Northwest Atl Fish Sci 22:219–248CrossRefGoogle Scholar
  21. Foster EA, Franks DW, Morrell LJ, Balcomb KC, Parsons KM, Van Ginneken A, Croft DP (2012) Social network correlates of food availability in an endangered population of killer whales, Orcinus orca. Anim Behav 83:731–736CrossRefGoogle Scholar
  22. Gazda S, Iyer S, Killingback T, Connor R, Brault S (2015) The importance of delineating networks by activity type in bottlenose dolphins (Tursiops truncatus) in Cedar Key Florida. R Soc Open Sci 2:40263CrossRefGoogle Scholar
  23. Gonzalvo J, Valls M, Cardona L, Aguilar A (2008) Factors determining the interaction between common bottlenose dolphins and bottom trawlers off the Balearic Archipelago (Western Mediterranean Sea). J Exp Mar Biol Ecol 367:47–52CrossRefGoogle Scholar
  24. Gregr EJ, Trites AW (2001) Predictions of critical habitat for five whale species in the waters of coastal British Columbia. Can J Fish Aquat Sci 58:1265–1285CrossRefGoogle Scholar
  25. Hee YY, Suratman S (2016) Physico-chemical parameters profile during dry and wet seasons in Southern South China Sea: Brunei Bay. Asian J Chem 28:2146–2152CrossRefGoogle Scholar
  26. Herman LM (1991) What the dolphin knows, or might know, in its natural world. In: Pryor K, Norris KS (eds) Dolphin societies: discoveries and puzzles. University of California Press, Los Angeles, pp 349–368Google Scholar
  27. Hill BJ, Wassenberg TJ (1990) Fate of discards from prawn trawlers in Torres Strait. Aust J Mar Freshw Res 41:53–64CrossRefGoogle Scholar
  28. Hines EM, Strindberg S, Junchumpoo C, Ponnampalam LS, Ilangakoon AD, Jackson Rickettes J, Monanunsap Ricketts J, Monanunsap S (2015) Line transect estimates of Irrawaddy dolphin abundance along the eastern gulf coast of Thailand. Front Mar Sci 2:1–10CrossRefGoogle Scholar
  29. Hof PR, Van Der Gucht E (2007) Structure of the cerebral cortex of the humpback whale, Megaptera novaeangliae (Cetacea, Mysticeti, Balaenopteridae). Anat Rec 290:1–31CrossRefGoogle Scholar
  30. Hoffman JM, Ponnampalam LS, Araújo-Wang C, Kuit SH, Hung SK, Wang JY (2016) Description of whistles of Irrawaddy dolphins (Orcaella brevirostris) from the waters of Matang, Peninsular Malaysia. Bioacoustics 25:1–10CrossRefGoogle Scholar
  31. Hogan MC (2011) The encyclopedia of earth. http://www.eoearth.org/view/article/156933/. Accessed 6 Apr 2016
  32. IUCN (2015) The IUCN Red List of Threatened Species. Version 2015-4. IUCN Species Survival Commission, GlandGoogle Scholar
  33. Jaaman SA (2010) Marine mammals in East Malaysia: distribution and interactions with fisheries. VDM Verlag Dr. Muller Aktiengesellschaft & Co. KG, SaarbruckenGoogle Scholar
  34. Jaaman SA, Lah-Anyi YU, Pierce GJ (2009) The magnitude and sustainability of marine mammal by-catch in fisheries in East Malaysia. J Mar Biol Assoc UK 89:907–920CrossRefGoogle Scholar
  35. Jaiteh VF, Allen SJ, Meeuwig JJ, Loneragan NR (2013) Subsurface behavior of bottlenose dolphins (Tursiops truncatus) interacting with fish trawl nets in northwestern Australia: implications for bycatch mitigation. Mar Mamm Sci 29:266–281CrossRefGoogle Scholar
  36. James PSBR, Rajagopalan M, Dan SS, Fernando AB, Selvaraj V (1989) On the mortality and stranding of marine mammals and turtles at Gahirmatha, Orissa from 1983 to 1987. J Mar Biol Assoc India 31:28–35Google Scholar
  37. Jefferson TA, Leatherwood S, Webber MA (1993) Marine mammals of the world. FAO species identification guide. FAO, Rome, p 320Google Scholar
  38. Jefferson TA, Karczmarski L, Kreb D, Laidre K, O’Corry-Crowe G, Reeves R, Rojas-Bracho L, Secchi E, Slooten E, Smith BD, Wang JY, Zhou K (2008) Orcaella brevirostris (Mahakam River subpopulation). (errata version published in 2016) The IUCN Red List of Threatened Species 2008: e.T39428A98842174. http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T39428A10237530.en. Accessed 11 Nov 2017
  39. Johnson CM, Moewe K (1999) Pectoral fin preference during contact in Commerson’s dolphins (Cephalorynchus commersoni). Aquat Mamm 25:73–78Google Scholar
  40. Joseph J, Nishizawa H, Arshaad WM, Kadir SAS, Jaaman SA, Bali J, Jamaludin NA, Katoh M (2016) Genetic stock compositions and natal origin of green turtle (Chelonia mydas) foraging at Brunei Bay. Glob Ecol Conserv 6:16–24CrossRefGoogle Scholar
  41. Kamaruzzan AS, Jaaman SA, Saleh E (2011) Effect of water parameters on the behaviour of indo-pacific humpback and Irrawaddy dolphins in Cowie Bay, Sabah, Malaysia. Borneo Sci 28:1–7Google Scholar
  42. Khalifa MA, Kamal MM, Adiwilaga EM, Sunuddin A (2014) Preliminary study on the distribution of Irrawaddy dolphin, Orcaella brevirostris, in Banten Bay. Open J Mar Sci 4:338–343CrossRefGoogle Scholar
  43. Kovacs CJ, Perrtree RM, Cox TM (2017) Social differentiation in common bottlenose dolphins (Tursiops truncatus) that engage in human-related foraging behaviors. PLoS One 12:1–14Google Scholar
  44. Kreb D, Budiono (2005) Cetacean diversity and habitat preferences in tropical waters of East Kalimantan, Indonesia. Raffles Bull Zool 53:149–155Google Scholar
  45. Kreb D, Budiono, Syachraini (2007) Status and conservation of Irrawaddy dolphins Orcaella brevirostris in the Mahakam River of Indonesia. In: Smith BD, Shore RG, Lopez A (eds) Status and conservation of freshwater populations of Irrawaddy dolphins. Wildlife Conservation Society, New York, pp 53–64Google Scholar
  46. Kuczaj SA II, Yeater DB (2007) Observations of rough-toothed dolphins (Steno bredanensis) off the coast of Utila, Honduras. J Mar Biol Assoc UK 87:141–148CrossRefGoogle Scholar
  47. Kuit SH, Ponnampalam LS, Fairul Izmal JH, Chong VC (2014) Cetacean research and a precautionary approach in developing dolphin-watching tourism in the coastal waters of the Matang mangroves. In: Proceedings of the Matang Mangrove Forest Management Conference, Perak, Malaysia, pp 27–39Google Scholar
  48. Leatherwood S, Reeves RR (1994) River dolphins: a review of activities and plans of the cetacean specialist group. Aquat Mamm 20:137–154Google Scholar
  49. Lloze R (1973) Contribution a l’etude anatomique histologique et biologique de l’Orcaella brevirostris (Gray, 1866) (Cetacea, Delphinidae) du Mekong. Thesis PhD. en Sciences Naturelles, L’Universite Paul Sabatier de Toulouse III, FranceGoogle Scholar
  50. Long SM (2014) Sarawak coastal biodiversity: a current status. Kuroshio Sci 8:71–84Google Scholar
  51. MacLeod K, Fairbairns R, Gill A, Fairbairns B, Gordon J, Blair-Myers C, Parsons ECM (2004) Seasonal distribution of minke whales Balaenoptera acutorostrata in relation to physiography and prey off the Isle of Mull, Scotland. Mar Ecol Prog Ser 277:263–274CrossRefGoogle Scholar
  52. Macleod CD, Bannon SM, Pierce GJ, Schweder C, Learmouth JA, Herman JS, Reid RJ (2005) Climate change and the cetacean community of north-west Scotland. Biol Cons 124:477–483CrossRefGoogle Scholar
  53. Mahmud AI, Jaaman SA, Muda AM, Muhamad HM, Zhang X, Scapini F (under preparation) Population estimation and occurrences of Irrawaddy dolphins Orcaella brevirostris (Owen in Gray, 1866) in the Brunei Bay, Malaysian watersGoogle Scholar
  54. Malaysian Meteorological Department (2008) General climate of Malaysia. http://www.met.gov.my/web/metmalaysia/services. Accessed 12 Apr 2016
  55. Mann J (1999) Behavioral sampling methods for cetaceans: a review and critique. Mar mamm Sci 15:102–122CrossRefGoogle Scholar
  56. Marino L, Connor RC, Fordyce RE, Herman LM, Hof PR, Lefebvre L, Lusseau D, McCowan B, Nimchinsky EA, Pack AA, Rendell L (2007) Cetaceans have complex brains for complex cognition. PLoS Biol 5:966–972CrossRefGoogle Scholar
  57. Marsh H, Lloze R, Heinsohand GE, Kasuya T (1989) Irrawaddy dolphin Orcaella brevirostris (Gray, 1866). In: Harrison RJ, Ridgway SH (eds) Handbook of marine mammals. Academic press, New York, pp 101–118Google Scholar
  58. Matsumoto BMM (2007) Fish and fisheries resources. In: Saleem M, Ejria S (eds) Coastal environmental profile of Brunei Bay, Sabah. Universiti Malaysia Sabah, Kota Kinabalu, pp 95–133Google Scholar
  59. McCluskey SM, Bejder L, Loneragan NR (2016) Dolphin prey availability and calorific value in an estuarine and coastal environment. Front Mar Sci 3:30CrossRefGoogle Scholar
  60. Michaud R (2005) Sociality and ecology of the odontocetes. In: Ruckstuhl KE, Neuhaus P (eds) Sexual segregation in vertebrates: ecology of the two sexes. Cambridge University Press, New York, pp 303–326Google Scholar
  61. Minton G, Peter C, Zulkifli Poh AN, Ngeian J, Braulik G, Hammond PS, Tuen AA (2013) Population estimates and distribution patterns of Irrawaddy dolphins (Orcaella brevirostris) and Indo-Pacific finless porpoises (Neophocaena phocaenoides) in the Kuching Bay, Sarawak. Raffles Bull Zool 61:877–888Google Scholar
  62. Mohamed M, Landner L (1993) Environmental impact assessment of a mixed tropical hardwood integrated pulp and paper mill—a case study. Environ Impact Assess Rev 13:353–374CrossRefGoogle Scholar
  63. Parra GJ (2005) Behavioural ecology of Irrawaddy dolphins, Orcaella brevirostris (Owen in Gray, 1866), and Indo-Pacific humpback dolphins, Sousa chinensis (Osbeck, 1765), in northeast Queensland, Australia: a comparative study. Ph.D. Thesis, James Cook University, AustraliaGoogle Scholar
  64. Perrin WF, Dolar MLL, Ortega E (1995) Osteological comparison of Bryde’s whales from the Philippines with specimens from other regions. Rep Int Whal Comm 46:409–413Google Scholar
  65. Peter C, Poh ANZ, Ngeian J, Tuen AA, Minton G (2016) Identifying habitat characteristics and critical areas for Irrawaddy dolphin, Orcaella brevirostris: implications for conservation. In: Das I, Tuen AA (eds) Naturalists, explorers and field scientists in South-East Asia and Australasia. Springer International Publishing, Switzerland, pp 225–238CrossRefGoogle Scholar
  66. Pilleri G, Gihr M (1974) Contribution to the knowledge of the cetaceans of southwest and monsoon Asia (Persian Gulf, Indus Delta, Malabar, Andaman Sea and Gulf of Siam). Investigations Cetacea 5:95–153Google Scholar
  67. Ponnampalam LS, Hines EM, Monanunsap S, Ilangakoon AD, Junchompoo C, Adulyanukosol K, Morse LJ (2013) Behavioral observations of coastal Irrawaddy dolphins (Orcaella brevirostris) in Trat province, eastern Gulf of Thailand. Aquat Mamm 39:401–408CrossRefGoogle Scholar
  68. Priyono A (1995) Habitat status and population of pesut (Orcaella brevirostris) in Indonesia. In: Workshop on the biology and conservation of small cetaceans and dugongs of Southeast Asia, Silliman University Marine Laboratory, Dumaguete, Philippines, pp 3Google Scholar
  69. Rajamani L, Marsh H (2010) Using parallel regional- and local-scale initiatives to inform conservation management of rare wildlife: a case study of the dugong Dugong dugon in Sabah, Malaysia. Endanger Species Res 13:17–23CrossRefGoogle Scholar
  70. Rayment W, Webster T (2009) Observations of Hector’s dolphins (Cephalorhynchus hectori) associating with inshore fishing trawlers at Banks Peninsula, New Zealand. NZ J Mar Freshw Res 43:911–916CrossRefGoogle Scholar
  71. Read AJ (2008) The looming crisis: interactions between marine mammals and fisheries. J Mamm 89:541–548CrossRefGoogle Scholar
  72. Reeves RR, Jefferson TA, Karczmarski L, Laidre K, O’Corry-Crowe G, Rojas-Bracho L, Secchi ER, Slooten E, Smith BD, Wang JY, Zhou K (2008) Orcaella brevirostris. The IUCN Red List of Threatened Species 2008: e.T15419A4579987Google Scholar
  73. Reilly SB (1990) Seasonal changes in distribution and habitat differences among dolphins in the eastern tropical Pacific. Mar Ecol Prog Ser 66:1–11CrossRefGoogle Scholar
  74. Selzer LA, Payne PM (1988) The distribution of white-sided (Lagenorhynchus acutus) and common dolphins (Delphinus delphis) vs. environmental features of the continental shelf of the northeastern United States. Mar Mamm Sci 4:141–153CrossRefGoogle Scholar
  75. Silvestre GT, Garces LR (2004) Population parameters and exploitation rate of demersal fishes in Brunei Darussalam (1989–1990). Fish Res 69:73–90CrossRefGoogle Scholar
  76. Simmonds MP, Isaac SJ (2007) The impacts of climate change on marine mammals: early signs of significant problems. Oryx 41:19–26CrossRefGoogle Scholar
  77. Sinha RK (2004) The Irrawaddy dolphins Orcaella brevirostris of Chilika Lagoon, India. J Bombay Nat Hist Soc 101:244–251Google Scholar
  78. Smith BD (2004) Orcaella brevirostris (Ayeyarwady River subpopulation). The IUCN Red List of Threatened Species 2004: e.T44556A10919593 http://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T44556A10919593.en. Accessed 11 Nov 2017
  79. Smith BD (2009) Irrawaddy dolphin (Orcaella brevirostris). In: Perrin WF, Würsig B, Thewissen JGM (eds) Encyclopedia of marine mammals. Academic Press, Burlington, pp 638–642CrossRefGoogle Scholar
  80. Smith BD, Beasley I (2004a) Orcaella brevirostris (Malampaya Sound subpopulation). The IUCN Red List of Threatened Species 2004: e.T44187A10858619. http://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T44187A10858619.en. Accessed 11 Nov 2017
  81. Smith BD, Beasley I (2004b) Orcaella brevirostris (Mekong River subpopulation). The IUCN Red List of Threatened Species 2004: e.T44555A10919444. http://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T44555A10919444.en. Accessed 11 Nov 2017
  82. Smith BD, Beasley I (2004c) Orcaella brevirostris (Songkhla Lake subpopulation). The IUCN Red List of Threatened Species 2004: e.T44557A10919695. http://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T44557A10919695.en. Accessed 11 Nov 2017
  83. Smith BD, Thant UH, Lwin JM, Shaw CD (1997) Investigation of cetaceans in the Ayeyarwady River and northern coastal waters of Myanmar. In: Morton B, Perrin WF (eds) Asian marine biology. Hong Kong University Press, Hong Kong, pp 173–194Google Scholar
  84. Smith BD, Beasley I, Buccat M, Calderon V, Evina R, Lemmuel De Valle J, Cadigal A, Tura E, Vistacion Z (2004) Status, ecology and conservation of Irrawaddy dolphins (Orcaella brevirostris) in Malampaya Sound, Palawan, Philippines. J Cetacean Res Manag 6:41–52Google Scholar
  85. Stacey PJ (1996) Natural history and conservation of Irrawaddy dolphins, Orcaella brevirostris, with special reference to the Mékong River. Lao PDR. M.Sc. Thesis, University of Victoria, CanadaGoogle Scholar
  86. Stacey PJ, Leatherwood S (1997) The Irrawaddy dolphin, Orcaella brevirostris: a summary of current knowledge and recommendations for conservation action. In: Morton B, Perrin WF (eds) Asian marine biology. Hong Kong University Press, Hong Kong, pp 195–214Google Scholar
  87. Stockin KA, Lusseau D, Binedell V, Wiseman N, Orams MB (2008) Tourism affects the behavioural budget of the common dolphin Delphinus sp. in the Hauraki Gulf, New Zealand. Mar Ecol Prog Ser 355:287–295CrossRefGoogle Scholar
  88. Straub KM, Mohrig D (2009) Constructional canyons built by sheet-like turbidity currents: observations from offshore Brunei Darussalam. J Sediment Res 79:24–39CrossRefGoogle Scholar
  89. Straub KM, Mohrig D, Pirmez C (2012) Architecture of an aggradational tributary submarine channel network on the continental slope offshore Brunei Darussalam. In: Prather BE, Deptuck ME, Mohrig B, Van Hoorn B, Wynn RB (eds) Application of the principles of seismic geomorphology to continental-slope and base-of-slope systems: case studies from seafloor and near-seafloor analogues. Society for Sedimentary Geology Special Publication 99, Oklahoma, USA, pp 13–30Google Scholar
  90. Sutaria D, Marsh H (2011) Abundance estimates of Irrawaddy dolphins in Chilika Lagoon, India, using photo identification based mark recapture methods. Mar Mamm Sci 27:338–348CrossRefGoogle Scholar
  91. Svane I (2005) Occurrence of dolphins and seabirds and their consumption of by-catch during prawn trawling in Spencer Gulf, South Australia. Fish Res 76:317–327CrossRefGoogle Scholar
  92. Tamaki N, Morisaka T, Taki M (2006) Does body contact contribute towards repairing relationships? The association between flipper-rubbing and aggressive behavior in captive bottlenose dolphins. Behav Proc 73:209–215CrossRefGoogle Scholar
  93. Waring GT, Gerrior P, Payne PM, Parry BL, Nicolas JR (1990) Incidental take of marine mammals in foreign fishery activities off the northeast United States, 1977–88. Fish Bull 88:347–360Google Scholar
  94. Weinrich MT, Belt CR, Morin D (2001) Behavior and ecology of the Atlantic white-sided dolphin (Lagenorhynchus acutus) in coastal New England waters. Mari Mamm Sci 17:231–248CrossRefGoogle Scholar
  95. Wilson B, Thompson PM, Hammond PS (1997) Habitat use by bottlenose dolphins: seasonal distribution and stratified movement patterns in the Moray Firth, Scotland. J Appl Ecol 34:1365–1374CrossRefGoogle Scholar
  96. Woan TS, Jaaman SA, Palaniappan PM (2013) A preliminary study of the population size of Irrawaddy dolphins (Orcaella brevirostris) in Cowie Bay, Sabah, Malaysia. J Trop Biol Conserv 10:23–26Google Scholar
  97. Yau KH (1988) Water quality of Brunei River and estuary. ASEAN/US Technical Workshop on Integrated Tropical Coastal Zone Management, SingaporeGoogle Scholar
  98. Yeater DB, Miller LE, Caffery KA, Kuczaj SA II (2013) Effects of an increase in group size on the social behavior of a group of rough-toothed dolphins (Steno bredanensis). Aquat Mamm 39:344–355CrossRefGoogle Scholar
  99. Zeeberg JJ, Corten A, De Graaf E (2006) Bycatch and release of pelagic megafauna in industrial trawler fisheries off Northwest Africa. Fish Res 78:186–195CrossRefGoogle Scholar

Copyright information

© Japan Ethological Society and Springer Japan KK, part of Springer Nature 2018

Authors and Affiliations

  • Anisul Islam Mahmud
    • 1
    • 2
  • Saifullah Arifin Jaaman
    • 2
  • Azmi Marzuki Muda
    • 2
  • Hairul Masrini Muhamad
    • 3
  • Xuelei Zhang
    • 4
  • Felicita Scapini
    • 1
  1. 1.Dipartimento di BiologiaUniversità degli Studi di Firenze (UNIFI)FlorenceItaly
  2. 2.Institute of Oceanography and Environment (INOS)Universiti Malaysia Terengganu (UMT)Kuala TerengganuMalaysia
  3. 3.Key Laboratory of Underwater Acoustics and Marine Information Technology, Department of Applied Marine Physics and Engineering, College of Ocean and EarthXiamen UniversityXiamenChina
  4. 4.First Institute of OceanographyState Oceanic AdministrationQingdaoChina

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