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catch in fisheries should be addressed urgently,through research, monitoring, and management.2.2.2 Steno bredanensisDistributionNo new information.Population/stock structureNo new information.sampling should be attempted in areas where thisspecies is seen on a regular basis, such as <strong>the</strong>Babuyan Islands. There is a need for assessment<strong>of</strong> <strong>the</strong> effects <strong>of</strong> by-catch in longline fisheries,especially for waters between <strong>the</strong> Philippinesand Taiwan. In light <strong>of</strong> <strong>the</strong> paucity <strong>of</strong> specimenmaterial for <strong>the</strong> region, samples (skulls and genetictissues) should be collected whenever possible.2.2.3 Sousa chinensisPopulation statusNo new information.Habitat statusNo new information.Directed catchesSpecimens thought to have been harpooned havebeen found in Taiwan fishing ports (Doc. 6). Thespecimen from <strong>the</strong> Philippines mentioned in <strong>the</strong>1995 workshop report may have been taken in apurse seine. Stocks in SE Asia may be affected by<strong>the</strong> infrequent drive-fishery catches in Japanesewaters.By-catchesBy-catch occurs on longlines and in drift gillnetsin Taiwanese waters (Doc. 6). This specieshas a tendency to be associated with logs ando<strong>the</strong>r floating objects, and it may <strong>the</strong>refore bepredisposed to capture in longline and purse seinefisheries. In <strong>the</strong> Babuyan Islands, Philippines,some by-catch may occur on longlines. Twostranded specimens from Vietnam had evidence<strong>of</strong> gillnet markings, and were probably by-caught(Doc. 4).Needs for additional researchNo directed research on this species has beenconducted anywhere in SE Asia. Such studieswould be beneficial, especially in areas <strong>of</strong> highfishing effort in deep water. Opportunistic biopsyDistributionThe distribution <strong>of</strong> <strong>the</strong> Indo-Pacific humpbackdolphin is fragmented in many areas. Wang andHung reported that <strong>the</strong> distribution in Chinesewaters has recently been shown to extend to <strong>the</strong>west coast <strong>of</strong> <strong>the</strong> main island <strong>of</strong> Taiwan. Verifiablerecords from <strong>the</strong> coast <strong>of</strong> China suggest that eightor nine populations <strong>of</strong> humpback dolphins mayexist from <strong>the</strong> Vietnam border to <strong>the</strong> mouth <strong>of</strong> <strong>the</strong>Yangzi River, mostly centered around <strong>the</strong> mouths<strong>of</strong> large rivers (Jefferson 2000b). Humpbackdolphins appear to be common in <strong>the</strong> HonTre River area (Doc. 3). Dolar reported anunconfirmed stranding in <strong>the</strong> Turtle Islands area<strong>of</strong> <strong>the</strong> Philippines. [Editors’ note: <strong>the</strong> specimenhas now been confirmed to be an Indo-Pacifichumpback dolphin]. The species has now beenconfirmed from Cambodian waters (Doc. 34).Population/stock structureThe taxonomy <strong>of</strong> <strong>the</strong> genus Sousa remainsconfused in spite <strong>of</strong> considerable recent research(IWC in press). Although West African humpbackdolphins (Sousa teuszii) clearly constitute aseparate species, <strong>the</strong> taxonomy <strong>of</strong> animals in <strong>the</strong>Indo-Pacific must await <strong>the</strong> completion <strong>of</strong> ongoingstudies using molecular genetic and morphometrictechniques. Some preliminary evidence suggeststhat eastern (chinensis-type) and western IndianOcean (plumbea-type) forms may be distinct(Jefferson 2000c). At this point, though, it isprudent to provisionally recognize only one<strong>Second</strong> <strong>Workshop</strong> on <strong>the</strong> Biology and Conservation <strong>of</strong> Small Cetaceans and Dugongs <strong>of</strong> SE Asia 69
species in <strong>the</strong> Indo-Pacific (S. chinensis). A newspecies, Sousa huangi, described from China (P.-L.Wang 1999) is thought to be based on a juvenilespecimen <strong>of</strong> S. chinensis.Population statusThe statement in <strong>the</strong> 1995 workshop reportthat <strong>the</strong> Hong Kong population <strong>of</strong> humpbackdolphins numbered only about 84 individualswas inaccurate. Jefferson reported that extensivevessel-based survey work has shown that <strong>the</strong> HongKong and Pearl River Estuary population is muchlarger than previously believed, numbering atleast 1,383 animals. Despite <strong>the</strong> many threats stillfacing this population, Jefferson (2000b) believes itto still be viable. About 60-80 animals occur in <strong>the</strong>Xiamen area (Doc. 9).Habitat statusHabitat degradation is rampant in many areas<strong>of</strong> <strong>the</strong> species’ range, including well-studiedregions such as Hong Kong and Xiamen, P.R.China. Plans to conserve <strong>the</strong> dolphin populationsare in place for both <strong>of</strong> <strong>the</strong>se areas. In HongKong, <strong>the</strong>se include long-term research andmonitoring <strong>of</strong> <strong>the</strong> population, <strong>the</strong> creation <strong>of</strong>marine reserves for protection <strong>of</strong> <strong>the</strong> species,development <strong>of</strong> a conservation plan, and <strong>the</strong>requirement <strong>of</strong> mitigation measures for marineconstruction and development activities (Doc.18,21). The flow <strong>of</strong> all major rivers <strong>of</strong> <strong>the</strong> westcoast <strong>of</strong> Taiwan have been greatly reduced by <strong>the</strong>construction <strong>of</strong> dams and reservoirs, <strong>the</strong> bankshave been altered by flood-control measures, an<strong>the</strong> estuaries are badly degraded. Estuaries along<strong>the</strong> west coast <strong>of</strong> Taiwan are badly degraded, asare several areas along <strong>the</strong> mainland Chinesecoast (Doc. 9). In addition, fishing activities are<strong>of</strong>ten more intense in <strong>the</strong> productive estuarineareas typically inhabited by humpback dolphinsthan elsewhere.Directed catchesNo directed fisheries for this species are known,apart from <strong>the</strong> fact that 12 humpback dolphinswere recently live-captured for display at a casinoin Cambodia (Doc. 34). Data on <strong>the</strong> number <strong>of</strong>animals live-captured in <strong>the</strong> Gulf <strong>of</strong> Thailandwere not available to this meeting. <strong>Workshop</strong>participants considered that although <strong>the</strong> numbertaken since <strong>the</strong> start <strong>of</strong> live-capture operations in<strong>the</strong> Gulf <strong>of</strong> Thailand is not known accurately, it mayhave been great enough to affect <strong>the</strong> wild sourcepopulation(s). In 1960-1962, 36 humpback dolphinswere deliberately killed by netting in Xiamen, P.R.China, in an attempt to reduce fishing interferenceand to test <strong>the</strong> feasibility <strong>of</strong> using <strong>the</strong>ir skin as asource <strong>of</strong> lea<strong>the</strong>r (Wang 1965).By-catchesBy-catches have been documented in almost everyarea where this species has been studied in <strong>the</strong>region. They most <strong>of</strong>ten involve set gillnet, driftnetand trawl fisheries. Wang reported that some liveanimals recently observed <strong>of</strong>f Taiwan had large scarson <strong>the</strong>ir caudal peduncles that were consistent withinjuries caused by net fisheries. Although <strong>the</strong>reare records <strong>of</strong> by-catch in mainland China, <strong>the</strong> lack<strong>of</strong> more extensive data on by-catch <strong>the</strong>re may bedue, at least in part, to <strong>the</strong> species’ protected status(Grade 1), which makes fishermen reluctant todisclose incidental catches (Doc. 9). One strandingon Taiwan’s Chinmen Island may have been <strong>the</strong>result <strong>of</strong> capture in a fish trap. Torey (Doc. 7)summarized six cases <strong>of</strong> certain or possible netentanglement in Hong Kong waters between 1975and 2000. She also reported that an on-boardfishery observer program was about to begin inHong Kong, and <strong>the</strong>refore better data may beavailable in <strong>the</strong> near future. Humpback dolphinsare taken in inshore gillnets along <strong>the</strong> nor<strong>the</strong>rncoast <strong>of</strong> Australia (Doc. 16).70 CMS Technical Series Publication Nº 9 - 2005
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CMS Technical Series Publication N
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Published by the U
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TABLE OF CONTENTSpage1. Preliminari
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AppendicesAppendix 1 - List <strong
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8 CMS Technical Series Publication
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10 CMS Technical Series Publication
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The cetacean species reviewed inclu
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Table 1. Major commercial Commonwea
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(2) State Legislation.In state wate
Page 19 and 20: (2) Identification of</stro
Page 21 and 22: Coastal speciesThe most frequently
Page 23 and 24: Coastal speciesThere are currently
Page 25 and 26: and Guangxi Provinces (Yang et al.
Page 27 and 28: Table 3. Records of</strong
Page 29 and 30: can be viewed as the</stron
Page 31 and 32: Workshop participa
Page 33 and 34: ioaccumulation have not yet been ex
Page 35 and 36: of fishermen who h
Page 37 and 38: are supplied to scholars and organi
Page 39 and 40: threats. Many marine mammal populat
Page 42: waters or recognize important inter
Page 47 and 48: James Cook University (Queensland,
Page 49 and 50: the last ten years
Page 51 and 52: proactive in engaging more staff an
Page 53 and 54: of SE Asia. Two sp
Page 55 and 56: San Francisco (Negros Oriental); Li
Page 57 and 58: Legal status and present management
Page 59 and 60: within 15 kilometers from t
Page 61 and 62: US, has actively participated in ce
Page 63 and 64: the project was su
Page 65 and 66: Recently, the camp
Page 67 and 68: Mekong River downstream of<
Page 69: porpoises in tropical waters <stron
Page 73 and 74: Population/stock structureNo new in
Page 75 and 76: Needs for additional researchStock
Page 77 and 78: waters of SE Asia,
Page 79 and 80: caused mortality is certainly large
Page 81 and 82: Needs for additional researchProper
Page 83 and 84: from SE Asia, it is known to occur
Page 85 and 86: 3.1.7 AustraliaDugongs occur all al
Page 87 and 88: Table 8. Conservation objectives id
Page 89 and 90: 3) Monitoring and assessment <stron
Page 91 and 92: Table 10. Outline of</stron
Page 93 and 94: The group agreed that this set <str
Page 95 and 96: 6. SUMMARY AND CONCLUSIONSThe works
Page 97 and 98: 96 CMS Technical Series Publication
Page 99 and 100: Bank, E. 1931. A popular account <s
Page 101 and 102: Dalebout, M. L., J. G. Mead, C. Sco
Page 103 and 104: Jaaman, S. A., E. Tangon, I. Isnain
Page 105 and 106: Lin, Y.-J. 1997. Mitochondrial DNA
Page 107 and 108: Smith, B.D., T. A. Jefferson, D. Ho
Page 109 and 110: Yang, W.-C. 2000. Morbillivirus inf
Page 111 and 112: CHOU Lien-SiangDepartment o
Page 113 and 114: Brian D. SMITHWildlife Conservation
Page 115 and 116: APPENDIX 3Agenda1. Preliminaries2.
Page 117 and 118: Doc. 22 Dugong conservation activit
Page 119 and 120: AreaDatesSurveyTypeEffortSpeciesNo.
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AreaDatesSurveyTypeEffortSpeciesNo.
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AreaDatesSurveyTypeEffortSpeciesNo.
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Phase ofActionPlan
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[Small cetaceans are defined to inc
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f) recognizing that by-catch in fis
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130 CMS Technical Series Publicatio
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APPENDIX 9Abstracts of</str
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The (IUCN Critically Endangered) Du
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Status of
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Cetacean Habitats in the</s
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Conservation of <s
Page 143 and 144:
Summary of Current
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Indonesia’s Cetacean Migration Co
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Conservation Effort to Protect <str
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The Status of <str
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Can the Developing
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Status and Conservation of<
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Legal Hunting of C
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Indo-Pacific Bottlenose Dolphins (T
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Feasibility Study of</stron
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Songs of a Humpbac
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