Management and reference points

Research Summary

Mark has done a variety of research on reference points. He developed the no-fishing plots that illustrated dynamic reference points and the relative impacts of fishing and the environment, which were used to provide management advice for the IATTC (Maunder and Watters, 2001). This led to his development of fishery impact plots to illustrate the impact on the population of the different fisheries (Wang et al. 2009), that are commonly used in several organizations. He developed the limit reference points current used at the IATTC, which are based on biomass and fishing levels that will reduce the recruitment to a given level (Maunder and Deriso, 2014). While still somewhat arbitrary, they are based on concepts used to define limit reference points and are less arbitrary than most limit reference points. These reference points, through based on theory, have astonished some people due to the low biomass levels they infer even when conservative values of the steepness of the stock-recruitment relationship are used. Recently, Mark and his colleagues developed a risk analysis method that uses model averaging to evaluate the probability of exceeding reference points (Maunder et al., 2020). Mark also did some early work on the influence of effort allocation among fishing gears and its influence on reference points and yield (Maunder, 2002) and economics (Sun et al. 2019).

Mark has conducted extensive research on management options and reference points for tropical tunas in the eastern Pacific Ocean. Much of this work is published as IATTC reports and not available in the peer reviewed literature. Much of this work is summarized in Maunder et al. (2021) and the reports listed in table 1 therein. This research includes Individual Vessel Limits (e.g. IATTC, 2013a), reference points (e.g. Maunder, 2013; Maunder and Deriso, 2014), area closures (e.g. Lennert-Cody et al., 2016), limits on Fish Aggregating Devices (FADs) (e.g. Lennert-Cody et al. 2017; Xu, H. et al., 2021), fishing vessel capacity limits (e.g. Maunder and Deriso, 2014), seasonal closures (e.g. ), catch limits (e.g. IATTC 2011; IATTC, 2013b),  individual vessel catch limits (e.g. Maunder and Suter, 2005; Maunder, 2006; IATTC, 2013a , size limits (e.g. Maunder and Tomlinson, 2006), Kobe plot (e.g. Maunder et al., 2012; Maunder and Aires-da-Silva, 2012), decision tables (e.g. Maunder and Aires-da-Silva, 2012; Minte-Vera et al., 2014), dynamic ocean management (e.g. Lopez et al., 2019a) ....

Marks other collaborative research on reference points includes looking at the influence of measures of spawning output (Minte-Vera et al., 2018), the influence of the stock-recruitment relationship on reference points (Maunder, 2012), the influence of growth, natural mortality, and the stock-recruitment relationship on reference points and how it relates to the shape of the production function used in surplus production models (Maunder and Starr, 1995; Maunder, 2003), evaluating the robustness of harvest rate reference points (Hilborn et al. 2002). Mark also wrote the entry on maximum sustainable yield for the Encyclopedia of Ecology (Maunder, 2008).       

Mark is a proponent of effort based management in short lived highly variable stocks like tuna (Squires et al. 2016).

Mark and Kevin Piner (2024) argue that evaluation of current status with respect to Biomass Reference Points, which is dependent on stock assessment estimates of biomass and depletion, is problematic for many stock that rely on indices of abundance and composition data to inform biomass information.

Relevant Papers

Maunder, M.N., Piner, K.R. 2024. Depletion Estimation, Stock–Recruitment Relationships, and Interpretation of Biomass Reference Points. Fishes 9, 447 https://www.mdpi.com/2410-3888/9/11/447

Maunder, M.N., Xu, H., Lennert-Cody, C.E., Valero, J.L., Aires-da-Silva, A., Minte-Vera, C. 2020. Implementing reference point-based fishery harvest control rules within a probabilistic framework that considers multiple hypotheses. IATTC Document SAC-11 INF-F REV. https://www.iattc.org/GetAttachment/46edbd8e-22f9-4bb3-8d26-d4cfd24a472c/SAC-11-INF-F_Implementing-risk-analysis.pdf

Sun CH, Maunder MN, Pan M, Silva AA, Bayliff WH, Compeán GA. 2019 Increasing the economic value of the eastern Pacific Ocean tropical tuna fishery: Tradeoffs between longline and purse-seine fishing. Deep-Sea Research Part II. 169-170, 104621. https://www.sciencedirect.com/science/article/pii/S0967064518303072

Minte-Vera, C.V., Maunder, M.N., Schaefer, K.M., Aires-da-Silva, A.M. 2018. The influence of metrics for spawning output on stock assessment results and evaluation of reference points: An illustration with yellowfin tuna in the eastern Pacific Ocean. Fisheries Research. 217: 35-45. https://www.sciencedirect.com/science/article/abs/pii/S0165783618302637

Squires, D., Maunder, M., Allen, R., …. 2016. Fish. Fish. 12185 https://onlinelibrary.wiley.com/doi/full/10.1111/faf.12185

Maunder, M.N. and Deriso, R.B. 2014. Proposal for biomass and fishing mortality limit reference points based on reduction in recruitment. IATTC Stock Assessment Report 15, 193–206. https://www.iattc.org/GetAttachment/57dae01b-461b-4278-b129-1161e9f650a5/Status%20of%20the%20tuna%20and%20billfish%20stocks%20in%202013

Maunder M.N. 2012. Evaluating the stock-recruitment relationship and management reference points: Application to summer flounder (Paralichthys dentatus) in the U.S. mid-Atlantic. Fisheries Research, 125–126: 20–26. https://www.sciencedirect.com/science/article/abs/pii/S0165783612000811

Wang, S-.P., Maunder, M.N., Aires-da-Silva, A. And Bayliff, W.H. 2009. Evaluating fishery impacts: application to bigeye tuna (Thunnus obesus) in the eastern Pacific Ocean. Fisheries Research 99: 106-111. https://www.sciencedirect.com/science/article/abs/pii/S0165783609001155

Maunder, M.N. 2008. Maximum Sustainable Yield. In Sven Erik Jørgensen and Brian D. Fath (Editor-in-Chief), General Ecology. Vol. 3 of Encyclopedia of Ecology, 5 vols. pp. 2292-2296 Oxford: Elsevier.

Maunder, M.N. 2003. Is it time to discard the Schaefer model from the stock assessment scientist’s toolbox? Fisheries Research, 61: 145-149. https://www.sciencedirect.com/science/article/abs/pii/S0165783602002734

Hilborn, R.H., Parma, A., and Maunder, M.N. 2002. Exploitation rate reference points for west coast rockfish: are they robust and are there better alternatives? North American Journal of Fisheries Management, 22: 365-375. https://www.tandfonline.com/doi/abs/10.1577/1548-8675(2002)022%3C0365%3AERRPFW%3E2.0.CO%3B2

Maunder, M.N. 2002. The relationship between fishing methods, fisheries management and the estimation of MSY. Fish and Fisheries, 3: 251-260. https://onlinelibrary.wiley.com/doi/epdf/10.1046/j.1467-2979.2002.00089.x

Maunder, M.N., Watters, G.M., 2001. Status of yellowfin tuna in the eastern Pacific Ocean. Inter-American Tropical Tuna Commission (IATTC), Stock Assessment Report 1, pp. 5–86. https://www.iattc.org/GetAttachment/c497aebf-1c78-4ca5-ad77-80fac55d95a1/Status%20of%20the%20tuna%20and%20billfish%20stocks%20in%201999

Maunder, M. N. and Starr, P. J. 1995. Sensitivity of management reference points to the ratio of Bmsy/B0 determined by the Pella Tomlinson shape parameter fitted to New Zealand rock lobster data. New Zealand Fisheries Assessment Research Document 95/10 p22. http://docs.niwa.co.nz/library/public/95_10_FARD.pdf

Workshop reports

Maunder, M.N. (compiled by) (2007). Report from the workshop on management strategies, IATTC, La Jolla, California (USA), 17-20 October 2006. 

Maunder, M.N. (compiled by) (2003). Workshop on reference points for tunas and billfishes.

Reports

Maunder, M.N., Lennert-Cody, C.E., Deriso, R.B., Aires-da-Silva, A.M., Lopez, J. 2021. Review of alternative conservation measures for the purse seine fishery for tropical tunas in the EPO. IATTC Document SAC-12 INF-B. https://www.iattc.org/GetAttachment/6a128dd6-061c-42a9-ab93-1cca5b8b48b3/SAC-12-INF-B_Review-of-conservation-alternatives.pdf

Maunder, M.N., Lopez, J., Lennert-Cody, C.E., Xu, H., Minte-Vera, C., Valero, J.L., Aires-da-Silva, A., Pulvenis, J-F. 2021. Managing the floating-object fishery for tropical tunas in the EPO: Additional precautionary measures recommended by the Staff. IATTC Document SAC-12-08. https://www.iattc.org/getattachment/8dc753a3-7b16-420f-a86b-0f0c98388dfe/SAC-12-08_Managing-the-floating-object-fishery.pdf

Xu, H., Lopez, J., Lennert-Cody, C.E., Maunder, M.N., Valero, J.L., Minte-Vera, C.V., Aires-da-Silva, A. 2021. The relationship between fishing mortality and the number of floating object sets for bigeye tuna in the eastern Pacific Ocean. IATTC Document FAD-05 INF-D. https://www.iattc.org/getattachment/85e4536f-9179-4a0e-b870-d670b00c43e9/FAD-05a-INF-D_Relationship-between-fishing-mortality-and-number-of-OBJ-sets-for-BET-in-the-EPO.pdf

Lopez, J., Lennert-Cody, C.E., Maunder, M.N., Aires-da-Silva, A., Xu, H., Minte-Vera, C., Valero, J,\.L., Pulvenis, J.F., Compeán, G. 2020. Managing the floating-object fishery for tropical tunas in the EPO: Supporting information for the pre cautionary additional measures recommended by the staff. IATTC Document SAC-11 INF-M. https://www.iattc.org/getattachment/0c722af2-037e-4ef2-94fe-be8ea91869ba/SAC-11-INF-M_FAD-management-measures.pdf

Lopez, J., Lennert-Cody, C.E., Maunder, M.N., Xu, H., Brodie, S., Jacox, M., Hartog, J. 2019a. Developing alternative conservation measures for bigeye tuna in the eastern Pacific Ocean: A dynamic ocean management approach. IATTC Document SAC-10 INF-D. https://www.iattc.org/getattachment/43e51264-3f0e-4fcb-90de-e1f5d448bcab/SAC-10-INF-D_Bigeye-tuna-Dynamic-Ocean-Management.pdf

Lopez, J., Lennert-Cody, C., Maunder, M., Altamirano, E. 2019b. Relationship between the characteristics of purse-seine vessels and fishing mortality (Project J.2.a): Progress report. IATTC Document SAC-10-10. https://www.iattc.org/getattachment/31f93d1c-df7e-4613-990c-d825986ded12/SAC-10-10_Relationship-between-purse-seine-vessel-characteristics-and-fishing-mortality.pdf

López, J., Lennert-Cody, C.E., Maunder, M.N., Vogel, N.W. Altamirano, E. 2019c. Causes of the increase in floating-object sets in the eastern Pacific Ocean in recent years: An analysis (Revised). IATTC Document SAC-10 INF-K. https://www.iattc.org/getattachment/81990ff9-af42-4e65-8d35-1e1a4792560a/SAC-10-INF-K-REV-09-May-19_Analysis-of-increase-in-floating-object-sets.pdf

IATTC. 2018. Responses to requests for data and analyses. IATTC Document IATTC-93 INF-A. https://www.iattc.org/getattachment/441ea1f4-f8b6-4e17-bf4f-4239e17d76ef/IATTC-93_INF-A-Responses-to-requests.pdf

Lennert-Cody, C.E., Moreno, G. Restrepo, V. Román, M.H., Maunder, M.N. 2017. A preliminary analysis of the relationship between the number of FAD deployments and the number of FAD sets for the EPO purse-seine fishery. IATTC document SAC-08-06d. https://www.iattc.org/getattachment/ea9ed8b2-ad9d-45e2-ad27-5ff3b8eb7adb/SAC-08-06d_Preliminary-study-of-FAD-deployments-versus-sets.pdf

IATTC. 2017a. Evaluation of tuna conservation proposals. IATTC Document IATTC-91-03a. https://www.iattc.org/getattachment/a9502851-06ce-442d-b742-50dcb3cc2f86/IATTC-91-03a_Evaluation-of-tuna-conservation-proposals.pdf

IATTC. 2017b. Evaluation of tuna conservation proposals. IATTC Document IATTC-91-03a Addendum 1. https://www.iattc.org/getattachment/aa8528a3-73ee-4c29-9ac7-1740c0586451/IATTC-91-03a-02_Addendum-1-Evaluation-of-tuna-conservation-proposals.pdf

IATTC. 2017c. Potential effects on tuna stocks of alternative management Schemes. IATTC Document IATTC-92 INF-C. https://www.iattc.org/getattachment/7496c4df-2e97-40c5-9fa5-447d89beb29b/IATTC-92-INF-C_Alternative-management-scenarios.pdf

IATTC. 2016a. Alternative management measures for tropical tunas in the EPO. IATTC Document IATTC-90 INF-B. https://www.iattc.org/getattachment/4575823a-76fe-4387-b18e-85eb2076bf87/IATTC-90-INF-B_Alternative-management-measures.pdf

IATTC. 2016b. Alternative management measures for tropical tunas in the EPO. IATTC Document IATTC-90 INF-B: Addendum 1. https://www.iattc.org/getattachment/49058707-9480-4ddf-9a1c-75d36a235dbb/IATTC-90-INF-B_Addendum-1-Alternative-management-measures.pdf

IATTC. 2016c. Options for measures for the conservation of tunas in the EPO, 2016. IATTC Document IATTC-90-04d(i). https://www.iattc.org/getattachment/ba65d144-caed-483d-b47a-8baa24ba031c/IATTC-90-04d(i)_Options-for-measures-for-the-conservation-of-tunas-in-the-eastern-Pacific-Ocean-2016.pdf

Lennert-Cody, C.E., Maunder, M.N., Aires-da-Silva, A., Román, M.H., Tsontos, M.V. 2016. Preliminary evaluation of several options for reducing bigeye tuna catch: spatial closures and gear restrictions. IATTC Document SAC-07-07e. https://www.iattc.org/getattachment/fa4a7951-4f0c-4f84-b33c-132fe41702c8/SAC-07-07e_Reducing-catches-of-bigeye-tuna.pdf

Maunder, M.N. and Aires-da-Silva, A. 2014. Developing conservation measures for bluefin tuna in the eastern and western regions of the Pacific Ocean: factors to consider and fishery impact analysis. IATTC Stock Assessment Report 15: 74-99. https://www.iattc.org/GetAttachment/57dae01b-461b-4278-b129-1161e9f650a5/No-15-2014_Status-of-the-tuna-and-billfish-stocks-in-2013.pdf

Maunder, M.N. Piner, K.R., and Aires-da-Silva, A. 2014. Stock status of Pacific bluefin tuna and the urgent need for management action. IATTC Stock Assessment Report 15: 47-73. https://www.iattc.org/GetAttachment/57dae01b-461b-4278-b129-1161e9f650a5/No-15-2014_Status-of-the-tuna-and-billfish-stocks-in-2013.pdf

Maunder, M.N. and Deriso, R.B. 2014. Evaluation of the relationship between active purse-seine fishing capacity and fishing mortality in eastern Pacific Ocean. IATTC Stock Assessment Report 15: 183-192. https://www.iattc.org/GetAttachment/57dae01b-461b-4278-b129-1161e9f650a5/No-15-2014_Status-of-the-tuna-and-billfish-stocks-in-2013.pdf

IATTC. 2013a. Individual-vessel limits for purse-seine vessels that fish on fish aggregating devices (FADs). IATTC Document SAC-04-11. https://www.iattc.org/getattachment/25a66680-aa1a-438f-b7df-13abd06a427a/SAC-04-11_Individual-Vessel-Quotas.pdf

IATTC. 2013b. Management options: total allowable catch (TAC) scheme. IATTC Document SAC-04 INF-D. https://www.iattc.org/getattachment/ec7b93c3-c48e-4b2c-87d5-7a7b5076e339/SAC-04-INF-D_Management-options-Total-Allowed-Catch-scheme.pdf

IATTC. 2011. Evaluation of total allowable catch system for the purse-seine and longline tuna fisheries in the eastern Pacific Ocean. IATTC Document IATTC-82-INF A. https://www.iattc.org/GetAttachment/8babf73b-26bd-4038-9003-b5b4f44eadd4/IATTC-82-INF-A_Evaluation-of-Total-Allowable-Catch-system-for-the-eastern-Pacific-Ocean.pdf

Maunder, M.N. and Deriso, R.B. 2014. Reference points and harvest rate control rules. IATTC Stock Assessment Report 14: 252-258.  https://www.iattc.org/GetAttachment/7463ef95-8e47-4ec0-ad48-5a168e5b8d31/No-14-2014_Status-of-the-tuna-and-billfish-stocks-in-2012.pdf

Minte-Vera, C.V., Maunder, M.N., and. Aires-da-Silva , A. 2014. Kobe II strategy matrix for the bigeye and yellowfin tuna stocks of the eastern Pacific Ocean in 2012. IATTC Stock Assessment Report 14: 259-268.  https://www.iattc.org/GetAttachment/7463ef95-8e47-4ec0-ad48-5a168e5b8d31/No-14-2014_Status-of-the-tuna-and-billfish-stocks-in-2012.pdf

Maunder, N.N. 2013. Reference points, decision rules, and management strategy evaluation for tunas and associated species in the eastern Pacific Ocean. IATTC Stock Assessment Report 13: 107:114.  https://www.iattc.org/GetAttachment/d336c4e2-b84b-4d3e-8153-9d245e8bcd4b/No-13-2012_Status-of-the-tuna-and-billfish-stocks-in-2011.pdf

Maunder, M.N. and Aires-da-Silva, A. 2012. Evaluation of the Kobe Plot and Strategy Matrix and their application to tuna in the EPO. IATTC Stock Assessment Report 12: 191:211. https://www.iattc.org/GetAttachment/59dd17fe-c85b-4c54-bc25-78c777be0af7/No-12-2012_Status-of-the-tuna-and-billfish-stocks-in-2010.pdf

Maunder, M.N., Aires-da-Silva, A., Deriso, R. 2012.A critical evaluation of the construction of the Kobe Strategy Matrix: lessons learned from bigeye tuna in the eastern Pacific Ocean. IATTC SAC-03-06C. https://iattc.org/GetAttachment/da33f7a4-ffdb-4c68-a25f-84f8e3e7fcc6/SAC-03-06c_Applicaton-of-Kobe-strategy-matrix-to-BET-DRAFT.pdf

Maunder, M.N., Aires-da-Silva, A., and Deriso, R.B. 2011. A fishery-impact-based management reference level for pacific Bluefin tuna in the eastern Pacific Ocean. IATTC Stock Assessment Report 11: 262-270.  https://www.iattc.org/GetAttachment/158a8a63-d94b-4bc5-a1ed-5ac43265f8e9/No-11-2011_Status-of-the-tuna-and-billfish-stocks-in-2009.pdf

Maunder, M.N. and Deriso, R.B. 2008. Using indicators of stock status when traditional reference points are not available: evaluation and application to skipjack tuna in the eastern Pacific Ocean. IATTC Stock Assessment Report 8: 229-248.  https://www.iattc.org/GetAttachment/b124e931-06ed-41e2-aec8-eff12e9d7a10/No-8-2007_Status-of-the-tuna-and-billfish-stocks-in-2006.pdf

Maunder, M.N. and Tomlinson, P. (2006) Evaluation of a management measure restricting catch below 60 cm. IATTC Working Group on Stock Assessments, 6th Meeting, SAR-7-12b.

Maunder, M.N. (2006) Catch limits for individual purse-seine vessels to reduce fishing mortality of bigeye tuna in the eastern Pacific Ocean. IATTC Working Group on Stock Assessments, 6th Meeting, SAR-7-12a.

Maunder, M.N. and Hoyle, S.D. (2006) Evaluation of the effect of resolution C-04-09. IATTC Working Group on Stock Assessments, 6th Meeting, SAR-7-12.

Maunder M.N. and Suter, J.M. (2005) Catch limits for individual purse-seine vessels to reduce fishing mortality on bigeye tuna in the eastern Pacific Ocean. IATTC Working Group on Stock Assessments, 6th Meeting, SAR-6-08b.

Maunder, M.N. and Hoyle, S.D. (2005) Evaluation of the effect of resolution C-04-09. IATTC Working Group on Stock Assessments, 6th Meeting, SAR-6-08a.

Breen, P., Kendrick, T., Starr, P.J. and Maunder, M.N. (1994) Results of the implementation of the rock lobster decision rule in 1994. New Zealand Fisheries Assessment Working Group Report 94/3.