JELLYFISH FISHERIES of the WORLD by Lucas Brotz B.Sc., The
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JELLYFISH FISHERIES OF THE WORLD by Lucas Brotz B.Sc., The University of British Columbia, 2000 M.Sc., The University of British Columbia, 2011 A DISSERTATION SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY in The Faculty of Graduate and Postdoctoral Studies (Zoology) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) December 2016 © Lucas Brotz, 2016 Abstract Fisheries for jellyfish (primarily scyphomedusae) have a long history in Asia, where people have been catching and processing jellyfish as food for centuries. More recently, jellyfish fisheries have expanded to the Western Hemisphere, often driven by demand from buyers in Asia as well as collapses of more traditional local finfish and shellfish stocks. Despite this history and continued expansion, jellyfish fisheries are understudied, and relevant information is sparse and disaggregated. Catches of jellyfish are often not reported explicitly, with countries including them in fisheries statistics as “miscellaneous invertebrates” or not at all. Research and management of jellyfish fisheries is scant to nonexistent. Processing technologies for edible jellyfish have not advanced, and present major concerns for environmental and human health. Presented here is the first global assessment of jellyfish fisheries, including identification of countries that catch jellyfish, as well as which species are targeted. A global catch reconstruction is performed for jellyfish landings from 1950 to 2013, as well as an estimate of mean contemporary catches. Results reveal that all investigated aspects of jellyfish fisheries have been underestimated, including the number of fishing countries, the number of targeted species, and the magnitudes of catches. Contemporary global landings of jellyfish are at least 750,000 tonnes annually, more than double previous estimates. Jellyfish have historically been understudied, resulting in the current dearth of knowledge on population dynamics and jellyfish fishery management. However, many of the tools used in traditional fisheries science, such as length-frequency analysis, can be applied to jellyfish, as demonstrated herein. Research priorities are identified, along with a prospective outlook on the future of jellyfish fisheries. ii Preface This dissertation represents a synthesis of existing information and original work that was led by the author, and includes information contributed from numerous collaborators. The work is presented here in its entirety in order to provide the entire global overview. However, selected material has been extracted as contributions to 6 publications, including 2 peer-reviewed journal articles, 2 book chapters, and 2 report sections. Specifically, selected information formed the basis of a peer-reviewed journal article [Brotz, L., A. Schiariti, J. López-Martínez, J. Álvarez-Tello, Y.-H.P. Hsieh, R.P. Jones, J. Quiñones, Z. Dong, A.C. Morandini, M. Preciado, E. Laaz, & H. Mianzan in press. Jellyfish fisheries in the Americas: origin, state of the art, and perspectives on new fishing grounds. Reviews in Fish Biology and Fisheries doi:10.1007/s11160-016-9445-y]. Information from Chapters 1-3 was used as the basis for a book chapter [Brotz, L. 2016. Jellyfish fisheries – a global assessment, pp. 110-124 in D. Pauly & D. Zeller (eds.) Global Atlas of Marine Fisheries: A Critical Appraisal of Catches and Ecosystem Impacts. Island Press, Washington, D.C., U.S.A.]; which also had an abbreviated version that was published in a report [Brotz, L. 2014. Jellyfish fisheries – a global assessment, pp. 77-81 in D. Pauly & D. Zeller (eds.) So long, and thanks for all the fish: The Sea Around Us, 1999-2014 – A Fifteen-Year Retrospective, a report to the Pew Charitable Trusts, University of British Columbia]. Material gleaned from this dissertation was also combined with additional contributions and was published as a peer-reviewed book chapter [Brotz, L. & D. Pauly in press. Studying jellyfish fisheries: toward accurate national catch reports and appropriate methods for stock assessments in G.L. Mariottini (ed.) Jellyfish: Ecology, Distribution Patterns and Human Interactions. Nova Publishers, Hauppauge, New York, U.S.A.]. A summary of relevant information, especially using selections from Chapter 3, will also be published as a report section [Brotz, L. in press. Jellyfish Fisheries in R. Brodeur & S. Uye (eds.) Jellyfish blooms around the North Pacific Rim: Causes and consequences, PICES Scientific Report No. 51]. iii Finally, some conclusions and opinions related to this dissertation, especially from Chapters 2 and 5, were also expressed in another peer-reviewed journal article [Gibbons, M.J., F. Boero, & L. Brotz 2016. We should not assume that fishing jellyfish will solve our jellyfish problem. ICES Journal of Marine Science 73(4): 1012-1018]. iv Table of contents Abstract ................................................................................................................................... ii Preface ..................................................................................................................................... iii Table of contents .................................................................................................................... v List of tables .......................................................................................................................... vii List of figures ....................................................................................................................... viii Acknowledgements .............................................................................................................. ix 1. Introduction .................................................................................................................... 1 2. From ocean to plate – aspects of jellyfish fisheries ................................................... 5 2.1. Ecology .................................................................................................................... 5 2.1.1. Target species ................................................................................................. 5 2.1.2. Life cycle ........................................................................................................ 10 2.2. Fisheries ................................................................................................................. 14 2.2.1. Fishing for jellyfish ...................................................................................... 14 2.2.2. Ecological implications................................................................................ 15 2.3. Use .......................................................................................................................... 21 2.3.1. Processing of edible jellyfish ...................................................................... 23 2.3.2. The edible product ....................................................................................... 28 2.3.3. Health effects of jellyfish consumption .................................................... 32 2.4. Management ......................................................................................................... 35 3. Reconstructing the global catch ................................................................................. 40 3.1. Methods ................................................................................................................. 42 3.1.1. Catch reconstruction .................................................................................... 42 3.1.2. Scaling factor ................................................................................................. 43 3.2. Results .................................................................................................................... 45 3.2.1. Estimating the contemporary global catch ............................................... 47 3.3. Countries fishing jellyfish ................................................................................... 53 3.3.1. Australia ........................................................................................................ 53 3.3.2. Bahrain ........................................................................................................... 57 3.3.3. Canada ........................................................................................................... 60 3.3.4. China .............................................................................................................. 62 3.3.5. Ecuador .......................................................................................................... 67 3.3.6. Honduras....................................................................................................... 68 3.3.7. India ............................................................................................................... 68 3.3.8. Indonesia ....................................................................................................... 73 3.3.9. Iran ................................................................................................................. 76 v 3.3.10. Japan .............................................................................................................. 76 3.3.11. Korea (Republic of) ...................................................................................... 78 3.3.12. Malaysia .......................................................................................................