Abstract
This paper evaluates the performance of different observer coverage rates and 9 possible sampling designs to estimate via computer simulation the total catch of target and non-target species for Chinese tuna longline fisheries in the Pacific Ocean. The stratified random samplings include different stratification schemes (based on target species or fishing areas) with different strategies for allocating observers. The observer data from 103 vessels between 2010 and 2019 were assumed to be the “true” sampling population. We concluded that the accuracy of catch estimates had a significant positive relationship with species detectability and observer coverage rate. On average, the accuracy improved by 50% when the coverage rate increases from 5 to 20%. Current simple random sampling in Chinese tuna longline fisheries is less efficient for monitoring many species. Stratified sampling designs based on the target species tended to yield the most accurate estimates of the total catch. Allocating the observers based on the scale of the fleets in different stratum seemed to be less efficient. The proportion of observers between different fleets should be adjusted according to different monitoring objectives. In general, a large proportion of observers are recommended to be allocated onboard vessels targeting bigeye tuna (Thunnus obesus). This study has the potential to have a significant contribution to future designs of the observer monitoring programs in Chinese tuna longline fishery and many other fisheries.
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Data availability
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
References
Allen M, Kilpatrick D, Armstrong M, Briggs R, Course G, Pérez N (2002) Multistage cluster sampling design and optimal sample sizes for estimation of fish discards from commercial trawlers. Fish Res 55(1–3):11–24. https://doi.org/10.1016/S0165-7836(01)00308-3
Amande MJ, Ariz J, Chassot E, de Molina AD, Gaertner D, Murua H, Pianet R, Ruiz J, Chavance P (2010) Bycatch of the European purse seine tuna fishery in the Atlantic Ocean for the 2003–2007 period. Aquat Living Resour 23(4):353–362. https://doi.org/10.1051/alr/2011003
Amandè MJ, Lennert-Cody CE, Bez N, Hall MA, Chassot E (2010) How much sampling coverage affects bycatch estimates in purse seine fisheries. IOTC-2010-WPEB-20. https://www.iotc.org/documents/how-much-sampling-coverage-affects-bycatch-estimates-purse-seine-fisheries. Accessed 20 Oct 2020
Amande MJ, Chassot E, Chavance P, Murua H, de Molina AD, Bez N (2012) Precision in bycatch estimates: the case of tuna purse-seine fisheries in the Indian Ocean. ICES J Mar Sci 69(8):1501–1510. https://doi.org/10.1093/icesjms/fss106
Anderson ORJ, Small CJ (2013) Review of tuna regional fisheries management organisations longline scientific observer programmes. ICCAT Collective Volume of Science Papers 69(5):2220–2232
Anderson ORJ, Small CJ, Croxall JP, Dunn EK, Sullivan BJ, Yates O, Black A (2011) Global seabird bycatch in longline fisheries. Endanger Species Res 14(2):91–106. https://doi.org/10.3354/esr00347
Babcock EA, Pikitch EK (2003) How much observer coverage is enough to adequately estimate bycatch? Pew Institute for Ocean Science, Miami, FL, and Oceana, Washington, DC
Cao J, Chen Y, Chang J-H, Chen X (2014) An evaluation of an inshore bottom trawl survey design for American lobster (Homarus americanus) using computer simulations. J Northwest Atl Fish Sci 46:27–39. https://doi.org/10.2960/J.v46.m696
Chen Y (1996) A Monte Carlo study on impacts of the size of subsample catch on estimation of fish stock parameters. Fish Res 26(3–4):207–223
Clarke S, Sato M, Small C, Sullivan B, Inoue Y, Ochi D (2014) Bycatch in longline fisheries for tuna and tuna-like species: a global review of status and mitigation measures. FAO Fisheries and Aquaculture Technical Paper 588:1–199
Cochran WG (1977) Sampling techniques, 3rd edn. Wiley, New York
Conquest L, Burr R, Donnelly R, Chavarria J, Gallucci V (1996) Sampling methods for stock assessment for small-scale fisheries in developing countries. Stock assessment quantitative methods and applications for small-scale fisheries. Lewis Publ., Florida, pp 179–225
Cotter AJR, Course G, Buckland ST, Garrod C (2002) A PPS sample survey of English fishing vessels to estimate discarding and retention of North Sea cod, haddock, and whiting. Fish Res 55(1–3):25–35
Dai X, Wu F, Wang X (2019) Annual report to the commission part 1: information on fisheries, research and statistics. SC15-AR/CCM–03. Fifteenth Regular Session of the WCPFC Scientific Committee, Pohnpei, Federated States of Micronesia, 12-20 August. https://www.wcpfc.int/node/42713. Accessed 20 Oct 2020
Davies SL (2003) Guidelines for developing an at-sea fishery observer programme. FAO Fisheries Technical Paper. FAO, Rome
Debski I, Pierre J, Knowles K (2016) Observer coverage to monitor seabird captures in pelagic longline fisheries. WCPFC-SC12-2016/EB-IP-07. Twelfth regular session of the Western and CentralPacific Fisheries Commission Scientific Committee. Bali, Indonesia, 3-11 August. https://www.wcpfc.int/node/27463. Accessed 20 Oct 2020
Faunce CH (2015) An initial analysis of alternative sample designs for the deployment of observers in Alaska. US Dep Commer, NOAA Tech Memo 1–33. https://doi.org/10.7289/V5/TM-AFSC-307
Gilman EL, Zimring M (2018) Meeting the objectives of fisheries observer programs through electronic monitoring. https://doi.org/10.13140/RG.2.2.28000.99846
Gilman E, Suuronen P, Chaloupka M (2017) Discards in global tuna fisheries. Mar Ecol Prog Ser 582:231–252
Gilman E, Weijerman M, Suuronen P (2017b) Ecological data from observer programmes underpin ecosystem-based fisheries management. ICES J Mar Sci 74(6):1481–1495. https://doi.org/10.1093/icesjms/fsx032
Hall M, Alverson D, Metuzals K (2000) By-catch : problems and solutions. Mar Pollut Bull 41:204–219
Huang HW (2011) Bycatch of high sea longline fisheries and measures taken by Taiwan: actions and challenges. Mar Policy 35(5):712–720. https://doi.org/10.1016/j.marpol.2011.02.012
Huang HW, Liu K-M (2010) Bycatch and discards by Taiwanese large-scale tuna longline fleets in the Indian Ocean. Fish Res 106(3):261–270. https://doi.org/10.1016/j.fishres.2010.08.005
Lawson T (2003) Observer coverage rates and the accuracy and reliability of estimates of CPUE for offshore longline fleets targeting South Pacific albacore. 16th Meeting of the Standing Committee on Tuna and and Billifsh, 9–16 July, Mooloolaba, Queensland, Australia. Oceanic Fisheries Programme, Secretariat of the Pacific Community, Noumea, New Caledonia. https://pacific-data.sprep.org/system/files/SWG_4_4.pdf. Accessed 20 Oct 2020
Lawson T (2004) Observer coverage rates and reliability of Cpue estimates for offshore longliners in tropical waters OF the Western And Central Pacific Ocean. 17th Meeting of the Standing Committee on Tuna and Billfish, Majuiro, Marshall Islands, 9-18 August, Oceanic Fisheries Programme, Secretariat of the Pacific Community, Noumea, New. https://pacific-data.sprep.org/system/files/SWG_4_1.pdf. Accessed 20 Oct 2020
Lohr SL (2009) Sampling: design and analysis. 2nd edn. Brooks/Cole, California
Lutchman I (2014) A review of best practice mitigation measures to address the problem of bycatch in commercial fisheries. Marine Stewardship Council Science Series 2:1–17
Miller TJ, Skalski JR, Ianelli JN (2007) Optimizing a stratified sampling design when faced with multiple objectives. ICES J Mar Sci 64(1):97–109. https://doi.org/10.1093/icesjms/fsl013
Nolan CP (1999) The International Conference on Integrated Fisheries Monitoring, Sydney, Australia, 1–5 February. Annals of the New York Academy of ences 58(2):96–108
Palmer MC, Hersey P, Marotta H, Shield GR, Cierpich SB (2016) The design and performance of an automated observer deployment system for the Northeastern United States groundfish fishery. Fish Res 179:33–46
Paloheimo JE, Chen Y (1996) Estimating fish mortalities and cohort sizes. Can J Fish Aquat Sci 53(7):1572–1579
Peatman T, Bell T, Allain V, Caillot S, Park T, Williams P, Tuiloma I, Panizza A, Fukofuka S, Smith N (2018) Summary of longline fishery bycatch at a regional scale, 2003-2017. SC13-ST/WP–03. Thirteenth Regular Session of the WCPFC Scientific Committee, Busan, Republic of Korea, 8-16 Augusthttps://www.wcpfc.int/node/31016. Accessed 20 Oct 2020
Punt AE (1999) Evaluating the costs and benefits of alternative monitoring programmes for fisheries management. Proceedings of the International Conference on Integrated Fisheries Monitoring, 209–222. Sydney, Australia, 1–5 February 1999. FAO, Rome
Reddy KG, Khan MGM, Khan S (2018) Optimum strata boundaries and sample sizes in health surveys using auxiliary variables. PLoS One 13(4):e0194787
Silburn J, Johnson DD, Booth DJ, Taylor MD (2020) The effect of subsampling when monitoring bycatch in a penaeid trawl fishery. Fish Res 224:105459
Swain A (2016) A note on optimum allocation for multiobjective sample surveys using fuzzy programming. Journal of Survey Statistics and Methodology 4(2):171–187
Van Dyke JM, Broder SP, Lee S, Paik J-H (2013) Governing ocean resources: new challenges and emerging regimes: a tribute to Judge Choon-Ho Park. Martinus Nijhoff, Belgium, pp 395–406. https://doi.org/10.1163/9789004252486
Xu B, Zhang C, Xue Y, Ren Y, Chen Y (2015) Optimization of sampling effort for a fishery-independent survey with multiple goals. Environ Monit Assess 187(5):252. https://doi.org/10.1007/s10661-015-4483-9
Acknowledgments
The work was supported by National Key R&D Programs of China (2019YFD0901404) and the scientific observer program of the Distant-Water Fishery of the Ministry of Agriculture and Rural Affairs of the People’s Republic of China (08-25). We would like to thank the National Data Centre for Distant-Water Fisheries of China for providing the observer data (2010–2019). We would also like to thank the observers, the captains of Lianfeng Du and other vessels, and the crew who helped contribute to the collection of data. We are grateful for Shandong Lidao Oceanic Technology Company Limited et al. for their cooperation, and we would like to thank Bai Li and other colleagues in the International Learning Network supported by the Paradise Foundation, Shanghai Ocean University, and the University of Maine for the discussion and revision of this paper.
Funding
This work was funded by National Key R&D Programs of China (2019YFD0901404) and the scientific observer program of the Distant-Water Fishery of the Ministry of Agriculture and Rural Affairs of the People’s Republic of China (08-25).
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JW contributed to the conception of the study, performed the data analyses, and wrote the manuscript; XG contributed to the conception of the study and wrote the original draft; JC contributed significantly to analysis and manuscript preparation; XD helped perform the analysis with constructive discussions; ST helped perform the analysis with constructive discussions and financially supported this work; YC analyzed existing literatures and provided a lot of work for the revision of the paper; all authors read and approved the final manuscript.
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Wang, J., Gao, X., Chen, J. et al. An evaluation of observer monitoring program designs for Chinese tuna longline fisheries in the Pacific Ocean using computer simulations. Environ Sci Pollut Res 28, 12628–12639 (2021). https://doi.org/10.1007/s11356-020-11266-1
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DOI: https://doi.org/10.1007/s11356-020-11266-1