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Natural mortality (M) is a powerful parameter in fisheries stock assessment and management; however, its precise estimation is extremely difficult. There is still a lack of estimates for several stocks. That is the case of demersal/deep-water species from the Azores archipelago, where demersal species are the second most important fishery based on landings and the most important in value. Species with higher commercial value and lacking M data were selected: Pagellus bogaraveo, Phycis phycis, Beryx splendens, Pontinus kuhlii, Helicolenus dactylopterus, Pagellus acarne, Beryx decadactylus and Pagrus pagrus. Life history parameters were gathered from literature. A literature review was performed to summarize all published indirect methods that are commonly used, as a simple and low-cost way to estimate M. This study aims to demonstrate the variability of natural mortality estimates based on the input parameters. It also constitutes the first attempt of M estimation for the most commercially important Azorean species. Twenty-six indirect methods were applied and about 70 % of the selected species had an average mortality estimate between 0.22 and 0.34 per year. The most well-studied species (Pagellus bogaraveo and Helicolenus dactylopterus) provided more accurate mean estimations (M = 0.30 and M = 0.27, respectively). Independent methods based on Tmax alone, or combined with L¥ or W¥, lowered the values. Methods based on reproduction parameters alone, or combined with growth, inflated the estimations. From the selection of life history parameters to the final estimation of M, the results of this study can fill the existing gap and represent a starting point for further studies.
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2. Abecassis, D., A.R. Costa, J.G. Pereira and M.R Pinho. 2006. Age and growth of bluemouth, Helicolenus dactylopterus (Delaroche, 1809) from the Azores. Fisheries Research 79: 148–154.
3. Afonso, P., F. Tempera and G. Menezes. 2008. Population structure and habitat preferences of red porgy (Pagrus pagrus) in the Azores, central north Atlantic. Fisheries Research 93: 338−345.
4. Alagaraja, K. 1984. Simple methods for estimation of parameters for assessing exploited fish stocks. Indian Journal of Fisheries 31: 177–208.
5. Alverson, D.L. and M.J. Carney. 1975. A graphic review of the growth and decay of population cohorts. ICES Journal of Marine Science 36: 133–143.
6. Andrews, K.I. and M. Mangel. 2012. Asymptotic size and natural mortality of long-lived fish for data poor stock assessments. Fisheries Research 127–128: 45–48.
7. Bayliff, W. 1967. Growth, mortality, and exploitation of the Engraulidae, with special reference to the anchoveta, Cetengraulis mysticetus, and the Colorado, Anchoa naso, in the eastern Pacific Ocean. Bulletin of the Inter-American Tropical Tuna Commission 12: 367– 408.
8. Begg, G.A., J.A. Hare and D.D. Sheehan. 1999. The role of life history parameters as indicators of stock structure. Fisheries Research 43: 141–163.
9. Beverton, R.J.H. and S.J. Holt. 1959. A review of the lifespans and mortality rates of fish in nature and their relation to growth and the other physiological characteristics. In: CIBA Foundation Colloquium on Aging. Vol. 5. The Lifespan of Animals (eds. G.E.W. Wolstenholme and M. O’Connor), pp. 142–180. J&A Churchill Ltd., London, UK.
10. Brodziak, J., J. Ianelli, K. Lorenzen and R.D. Methot. 2011. Estimating Natural Mortality in Stock Assessment Applications. NOAA Technical Memorandum NMFS-F/SPO-119. Alaska Fisheries Science Center, Seattle, Washington. 38 pp.
11. Cadima, E.L. 2003. Fish Stock Assessment Manual. FAO Fisheries Technical Paper. No. 393. Food and Agriculture Organization of the United Nations, Rome, Italy. 161 pp.
12. Charnov, E.L. and D. Berrigan. 1990. Dimensionless numbers and life history evolution: age of maturity versus the adult lifespan. Evolutionary Ecology 4: 273–275.
13. Chen, S. and S. Watanabe. 1989. Age dependence of natural mortality coefficient in fish population dynamics. Nippon Suisan Gakkaishi 55: 205–208.
14. Cubillos, L.A. 2003. An approach to estimate the natural mortality rate in fish stocks. Worldfish Center Quarterly 26(1): 17–19.
15. Cubillos, L.A., R. Alarcon and A. Brante. 1999. Empirical estimates of natural mortality for the Chilean hake (Merluccius gayi): evaluation of precision. Fisheries Research 42: 147–153.
16. Da Silva, H.M. and M.R. Pinho. 2008. Small-scale fishing on Seamounts. In: Seamounts: ecology, fisheries and conservation (eds. T.J. Pitcher, T. Morato, P.J.B. Hart, M.R. Clark, N. Haggan and R.S. Santos), pp. 335–360. Fisheries and Aquatic Resource Series, Blackwell Scientific, Oxford, UK.
17. Djabali, F., A. Mehailia, M. Koudil and B. Brahmi. 1993. Empirical equations for the estimation of natural mortality in Mediterranean teleosts. Naga, the ICLARM Quarterly 16: 35–37.
18. Estácio, S., A. Mendonça, H. Krug, G.M. Menezes, J. Branco and M.R. Pinho. 2001. Aspects of the reproduction of six demersal fishes captured in the Azores Archipelago. Arquipelago Life and Marine Sciences Supplement 2B: 83–94.
19. Frisk, M.G., T.J. Miller and M.J. Fogarty. 2001. Estimation and analysis of biological parameters in elasmobranch fishes: A comparative life history study. Canadian Journal of Fisheries and Aquatic Sciences 58: 969–981.
20. Gislason, H., N. Daan, J.C. Rice and J.G. Pope. 2010. Size, growth, temperature and the natural mortality of marine fish. Fish and Fisheries 11: 149–158.
21. Griffiths, D. and C. Harrod. 2007. Natural mortality, growth parameters and environmental temperature in fishes revisited. Canadian Journal of Fisheries and Aquatic Sciences 64: 249–255.
22. Groeneveld, J.C. 2000. Stock assessment, ecology and economics as criteria for choosing between trap and trawl fisheries for spiny lobster Palinurus delagoae. Fisheries Research 48: 141–155.
23. Gunderson, D.R. 1980. Using r-K selection theory to predict natural mortality. Canadian Journal of Fisheries and Aquatic Sciences 37: 2266–2271.
24. Gunderson, D.R. 1997. Trade-off between reproductive effort and adult survival in oviparous and viviparous fishes. Canadian Journal of Fisheries and Aquatic Sciences 54: 990–998.
25. Gunderson, D.R. and P.H. Dygert. 1988. Reproductive effort as a predictor of natural mortality rate. ICES Journal of Marine Science 44: 200–209.
26. Hamel, O.S. 2015. A method for calculating a meta-analytical prior for the natural mortality rate using multiple life history correlates. ICES Journal of Marine Science 72(1): 62–69.
27. Hewitt, D.A. and J.M. Hoenig. 2005. Comparison of two approaches for estimating natural mortality based on longevity. Fishery Bulletin 103: 433–437.
28. Hewitt, D.A., D.M. Lambert, J.M. Hoenig, R.N. Lipcius, D.B. Bunnell and T.J. Miller. 2007. Direct and indirect estimates of natural mortality for Chesapeake Bay blue crab. Transactions of the American Fisheries Society 136(4): 1030–1040.
29. Hoenig, J.M. 1983. Empirical use of longevity data to estimate total mortality rates. Fishery Bulletin 82: 898–903.
30. Hoenig, J.M., A.Y.H. Then, E.A. Babcock, N.G. Hall, D.A. Hewitt and S.A. Hesp. 2016. The logic of comparative life history studies for estimating key parameters, with a focus on natural mortality rate. ICES Journal of Marine Science 73(10): 2453–2467.
31. International Council for the Exploration of the Sea (ICES). 2012. Report of the Working Group on the Biology and Assessment of Deep-sea Fisheries Resources (WGDEEP), 28 March-5 April, Copenhagen, Denmark. ICES CM 2012/ACOM:17. 9. International Council for the Exploration of the Sea, Copenhagen, Denmark. 29 pp.
32. International Council for the Exploration of the Sea (ICES). 2019. Working Group on the Biology and Assessment of Deep-sea Fisheries Resources (WGDEEP). ICES Scientific Reports. 1: 21. International Council for the Exploration of the Sea, Copenhagen, Denmark. 988 pp.
33. Isidro, E.J. 1987. Age and Growth of the Bluemouth, Helicolenus dactylopterus (De la Roche, 1809) Off the Azores. International Council for the Exploration of the Sea CM 19871G: 63. International Council for the Exploration of the Sea, Copenhagen, Denmark. 6 pp.
34. Isidro, E.J. 1996. Biology and population dynamics of selected demersal fish species of the Azores Archipelago. Ph.D. Thesis, University of Liverpool, Isle of Man, UK. 249 pp.
35. Jensen, A.L. 1996. Beverton and Holt life history invariants result from optimal tradeoff of reproduction and survival. Canadian Journal of Fisheries and Aquatic Sciences 53: 820–822.
36. Johnson, K.F., C.C. Monnahan, C.R. McGilliard, K.A. Vert-pre, S.C. Anderson, C.J. Cunningham and C.S. Szuwalski. 2014. Time-varying natural mortality in fisheries stock assessment models: identifying a default approach. ICES Journal of Marine Science 72(1): 137–150.
37. Kenchington, T.J. 2014. Natural mortality estimators for information-limited fisheries. Fish and Fisheries 15: 533–562.
38. Krug, H. 1989. The Azorean blackspot seabream, Pagellus bogaraveo (Briinnich, 1768) (Teleostei, Sparidae): Age and growth. Cybium 13(4): 347–355.
39. Krug, H. 1994. Biologia e avaliação do stock açoreano de goraz, Pagellus bogaraveo. Ph.D. Thesis, University of the Azores, Horta, Portugal. 193 pp.
40. Krug, H., D. Carvalho and J.A. González. 2011. Age and growth of the alfonsino Beryx decadactylus (Cuvier, 1829) from the Azores, Madeira and Canary Islands, based on historical data. Arquipelago: Life and Marine Sciences 28: 25–31.
41. Krug, H., D. Rosa, G. Menezes and M.R. Pinho. 1998. Age and Growth of Some Demersal Species of the Azores. International Council for the Exploration of the Sea, Copenhagen, Denmark. 11 pp.
42. Krug, H., D. Rosa, H.M. Silva and G. Menezes. 1997. Age and Growth of Demersal Species from Azores. Semana das pescas dos Açores, Horta.
43. Lorenzen, K. 1996. The relationship between body weight and natural mortality in juvenile and adult fish: A comparison of natural ecosystems and aquaculture. Journal of Fish Biology 49: 627–647.
44. Maunder, M.N. and R.A. Wong. 2011. Approaches for estimating natural mortality: Application to summer flounder (Paralichthys dentatus) in the U.S. mid-Atlantic. Fisheries Research 111: 92–99.
45. McCoy, M.W. and J.F. Gillooly. 2008. Predicting natural mortality rates of plants and animals. Ecology Letters 11: 710–716.
46. McGurk, M.D. 1986. Natural mortality of marine pelagic fish eggs and larvae: role of spatial patchiness. Marine Ecology Progress Series 34: 227–242.
47. Menezes, G., J. Delgado, H. Krug, M.R. Pinho, H. Silva and D. Carvalho. 1998. Design Optimization and Implementation of Demersal Survey Cruises in the Macaronesian Archipelagos. Internal Report Series No. 3/98. University of Azores, Horta, Portugal. 162 pp.
48. Menezes, G., M.F. Sigler, H.M. Silva and M.R. Pinho. 2006. Structure and zonation of demersal fish assemblages off the Azores Archipelago (mid-Atlantic). Marine Ecology Progress Series 324: 241–260.
49. Monteiro, S.V. 2014. Ecology and fisheries of the forkbeard Physis physis (L., 1776) in the Azores Region ICES(Xa2). Master Thesis, University of the Azores, Horta, Portugal. 96 pp.
50. Morato T., W.W.L. Cheung and T.J. Pitcher. 2004. Additions to Froese and Sampang’s checklist of seamount fishes. In: Seamounts: Biodiversity and Fisheries. Fisheries Centre Research Reports, 12(5), Appendix 1 (eds. T. Morato and D. Pauly), pp. 1-6. Fisheries Centre, University of British Columbia, Vancouver, Canada.
51. Morato, T. 2012. Description of Environmental Issues, Fish Stocks and Fisheries in the EEZs around the Azores and Madeira. Report for the European Commission, Directorate-General Maritime Affairs and Fisheries, Brussels, Belgium. 63 pp.
52. Ohsumi, S. 1979. Interspecies relationships among some biological parameters in Cetaceans and estimation of the natural mortality coefficient of the Southern Hemisphere Minke Whale. In: Report of the International Whaling Commission (ed. E. Donovan), pp. 397–406. International Whaling Commission, Cambridge, UK.
53. Pauly, D. 1980. On the interrelationships between natural mortality, growth parameters, and mean environmental temperature in 175 fish stocks. ICES Journal of Marine Science 39: 175–192.
54. Pauly, D. and C. Binohlan. 1996. FishBase and AUXIM as tools for comparing the life history patterns, growth and natural mortality of fish: applications to snappers and groupers. Proceedings of International Center for Living Aquatic Resources Management 1996: 218–243.
55. Pascual, M.A. and O.O. Iribarne. 1993. How good are empirical predictions of natural mortality? Fisheries Research 16: 17–24.
56. Peterson, I. and J.S. Wroblewski. 1984. Mortality rate of fishes in the pelagic ecosystem. Canadian Journal of Fisheries and Aquatic Sciences 41: 1117–1120.
57. Pinho, M.R. and G. Menezes. 2006. Azorean deepwater fishery: Ecosystem, species, fisheries and management approach aspect. Proceedings of Conference on the Governance and Management of Deep-sea Fisheries 2006: 330–343.
58. Pinho, M.R. and G. Menezes. 2009. Azorean demersal fishery. Boletim do Núcleo Cultural da Horta 18: 85–102.
59. Punt, A.E., C. Castillo–Jordán, O.S. Hamel, J.M. Cope, M.N. Maunder and J.N. Ianelli. 2021. Consequences of error in natural mortality and its estimation in stock assessment models. Fisheries Research 233: 105759. DOI: 10.1016/j.fishres.2020.105759.
60. Ralston, S. 1987. Mortality rates of snappers and groupers. In: Tropical Snappers and Groupers: Biology and Fisheries Management (eds. J.J. Polovina and S. Ralston), pp. 375–404. Westview Press, Boulder, USA.
61. Rikhter, V.A. and V.N. Efanov. 1976. On One of the Approaches to Estimation of Natural Mortality of Fish Populations. International Commission for the Northwest Atlantic Fisheries, Kaliningrad, Russia (USSR). 12 pp.
62. Roff, D.A. 1984. The evolution of life history parameters in teleosts. Canadian Journal of Fisheries and Aquatic Sciences 41: 989–1000.
63. Rosa, A., G. Menezes, O. Melo and M.R. Pinho. 2006. Weight-length relationships of 33 demersal fish species from Azores. Archipelago Life and Marine Science 80: 329–332.
64. Sekharan, K.V. 1975. Estimates of the stocks of oil sardine and mackerel in the present fishing grounds off the West coast of India. Indian Journal of Fisheries 21: 177–182.
65. Serafim, M. and H. Krug. 1995. Age and growth of the red porgy, Pagrus pagrus (Linnaeus, 1758) (Pisces: Sparidae) in Azorean Waters. Arquipelago: Life and Marine Sciences 13: 11–20.
66. Silva, P., H. Krug and M.R. Pinho. 2015. Natural Mortality for the Red Seabream (Pagellus bogaraveo) Stock from the Azores (ICES Xa2). Working document WGDEEP 2015. International Council for the Exploration of the Sea, Copenhagen, Denmark. 25 pp.
67. Tanaka, S. 1960. Studies on the dynamics and the management of fish populations. Bulletin of Tokai Regional Fisheries Research Laboratory 28: 1–200.
68. Taylor, C.C. 1960. Temperature, growth and mortality the Pacific cockle. ICES Journal of Marine Science 26(1): 117–124.
69. Then, A.Y., J.M. Hoenig, N.G. Hall and D.A. Hewitt. 2015. Evaluating the predictive performance of empirical estimators of natural mortality rate using information on over 200 fish species. ICES Journal of Marine Science 72(1): 82–92.
70. Vetter, E.L. 1988. Estimation of natural mortality in fish stocks: a review. Fishery Bulletin 86: 25–43.
71. Zhang, C.I. and B.A. Megrey. 2006. A revised Alverson and Carney model for estimating the instantaneous rate of natural mortality. Transactions of the American Fisheries Society 135: 620–633.