Philippa Kaur

1.
Irigoien, X. et al. Large mesopelagic fishes biomass and trophic efficiency in the open ocean. Nat. Commun. 5, 3271 (2014).
ADS  PubMed  PubMed Central  Article  CAS  Google Scholar 
2.
Gjøsaeter, J. & Kawaguchi, K. A review of the world resources of mesopelagic fish. FAO Fish. Tech. Pap. 193, 123–134 (1980).
Google Scholar 

3.
Sutton, T. T. et al. A global biogeographic classification of the mesopelagic zone. Deep. Res. Part I 126, 85–102 (2017).
Article  Google Scholar 

4.
Priede, I. G. Deep-sea fishes: Biology, diversity, ecology and fisheries. (Cambridge University Press, 2017). doi:https://doi.org/10.1017/9781316018330.

5.
Sutton, T. T. Vertical ecology of the pelagic ocean: classical patterns and new perspectives. J. Fish Biol. 83, 1508–1527 (2013).
CAS  PubMed  Article  Google Scholar 

6.
Boyd, P. W., Claustre, H., Levy, M., Siegel, D. A. & Weber, T. Multi-faceted particle pumps drive carbon sequestration in the ocean. Nature 568, 327–335 (2019).
ADS  CAS  PubMed  Article  Google Scholar 

7.
Cavan, E. L., Laurenceau-Cornec, E. C., Bressac, M. & Boyd, P. W. Exploring the ecology of the mesopelagic biological pump. Prog. Oceanogr. 176, 102–125 (2019).
Article  Google Scholar 

8.
Davison, P. C., Checkley, D. M., Koslow, J. A. & Barlow, J. Carbon export mediated by mesopelagic fishes in the northeast Pacific Ocean. Prog. Oceanogr. 116, 14–30 (2013).
ADS  Article  Google Scholar 

9.
Albuquerque, F. V., Navia, A. F., Vaske-Jr, T., Crespo, O. & Hazin, F. H. V. Trophic ecology of large pelagic fish in the Saint Peter and Saint Paul Archipelago Brazil. Mar. Freshw. Res. 70, 1402–1418 (2019).
Article  Google Scholar 

10.
Battaglia, P. et al. Feeding habits of the Atlantic bluefin tuna, Thunnus thynnus (L. 1758), in the central Mediterranean Sea (Strait of Messina). Helgol. Mar. Res. 67, 97–107 (2013).
ADS  Article  Google Scholar 

11.
Cherel, Y., Fontaine, C., Richard, P. & Labat, J. P. Isotopic niches and trophic levels of myctophid fishes and their predators in the Southern Ocean. Limnol. Oceanogr. 55, 324–332 (2010).
ADS  CAS  Article  Google Scholar 

12.
Drazen, J. C. & Sutton, T. T. Dining in the deep: the feeding ecology of deep-sea fishes. Ann. Rev. Mar. Sci. 9, 1–26 (2017).
Article  Google Scholar 

13.
John, M. A. S. et al. A dark hole in our understanding of marine ecosystems and their services: perspectives from the mesopelagic community. Front. Mar. Sci. 3, 1–6 (2016).
Google Scholar 

14.
Hidalgo, M. & Browman, H. I. Developing the knowledge base needed to sustainably manage mesopelagic resources. ICES J. Mar. Sci. 76, 609–615 (2019).
Article  Google Scholar 

15.
Martin, A. et al. The oceans’ twilight zone must be studied now, before it is too late. Nature 580, 26–28 (2020).
ADS  CAS  PubMed  Article  Google Scholar 

16.
Levin, L., Baker, M. & Thomson, A. Deep-ocean climate change impacts on habitat, fish and fisheries. (FAO, 2019).

17.
Brito-Morales, I. et al. Climate velocity reveals increasing exposure of deep-ocean biodiversity to future warming. Nat. Clim. Chang. 10, 576–581 (2020).
ADS  CAS  Article  Google Scholar 

18.
Davison, P. & Asch, R. G. Plastic ingestion by mesopelagic fishes in the North Pacific Subtropical Gyre. Mar. Ecol. Prog. Ser. 432, 173–180 (2011).
ADS  Article  Google Scholar 

19.
Drazen, J. C. et al. Midwater ecosystems must be considered when evaluating environmental risks of deep-sea mining. Proc. Natl. Acad. Sci. 117, 17455–17460 (2020).
PubMed  Article  Google Scholar 

20.
Eduardo, L. N. et al. Hatchetfishes (Stomiiformes: Sternoptychidae) biodiversity, trophic ecology, vertical niche partitioning and functional roles in the western Tropical Atlantic. Prog. Oceanogr. 186, 102389 (2020).
Article  Google Scholar 

21.
Olivar, M. P. et al. Mesopelagic fishes across the tropical and equatorial Atlantic: biogeographical and vertical patterns. Prog. Oceanogr. 151, 116–137 (2017).
ADS  Article  Google Scholar 

22.
Cherel, Y., Romanov, E. V., Annasawmy, P., Thibault, D. & Ménard, F. Micronektonic fish species over three seamounts in the southwestern Indian Ocean. Deep. Res. Part II, 176 (2020).

23.
Sutton, T. T. & Hopkins, T. L. Trophic ecology of the stomiid (Pisces: Stomiidae) fish assemblage of the eastern Gulf of Mexico: strategies, selectivity and impact of a top mesopelagic predator group. Mar. Biol. 127, 179–192 (1996).
Article  Google Scholar 

24.
Carmo, V., Sutton, T., Menezes, G., Falkenhaug, T. & Bergstad, O. A. Feeding ecology of the Stomiiformes (Pisces) of the northern Mid-Atlantic Ridge. 1. The Sternoptychidae and Phosichthyidae. Prog. Oceanogr. 130, 172–187 (2015).

25.
Richards, T. M. et al. Trophic ecology of meso- and bathypelagic predatory fishes in the Gulf of Mexico. ICES J. Mar. Sci. 76, 662–672 (2018).
Article  Google Scholar 

26.
Sutton, T. T. & Hopkins, T. L. Species composition, abundance, and vertical distribution of the stomiid (Pisces: Stomiiformes) fish assemblage of the Gulf of Mexico. Bull. Mar. Sci. 59, 530–542 (1996).
Google Scholar 

27.
Butler, M., Bollens, S. M., Burkhalter, B., Madin, L. P. & Horgan, E. Mesopelagic fishes of the Arabian Sea: Distribution, abundance and diet of Chauliodus pammelas, Chauliodus sloani, Stomias affinis, and Sòtomias nebulosus. Deep. Res. Part II 48, 1369–1383 (2001).
Article  Google Scholar 

28.
Battaglia, P., Ammendolia, G., Esposito, V., Romeo, T. & Andaloro, F. Few but relatively large prey: trophic ecology of Chauliodus sloani (Pisces: Stomiidae) in deep waters of the Central Mediterranean Sea. J. Ichthyol. 58, 8–16 (2018).
Article  Google Scholar 

29.
Gibbs, R. H. Chauliodontidae. in Fishes of the north-eastern Atlantic and the Mediterranean (eds. Whitehead, P. J. ., Bauchot, M. L., Hureau, J. C., Nielsen, J. & Tortonese, E.) 336–337 (Unesco, 1989).

30.
Harrison, I. J. The living marine resources of the Western Central Atlantic. Volume 2: Bony fishes part 1 (Acipenseridae to Grammatidae). FAO Species Identif. Guid. Fish. Purp. Am. Soc. Ichthyol. Herpetol. Spec. Publ. No. 5 601–1374 (2003).

31.
Eduardo, L. N. et al. Length-weight relationship of twelve mesopelagic fishes from the western Tropical Atlantic. J. Appl. Ichthyol. (2020) https://doi.org/10.1111/jai.14084.

32.
Figueiredo, G. A., Schwamborn, R., Bertrand, A., Munaron, J.-M. & Le Loc’h, F. Body size and stable isotope composition of zooplankton in the western Tropical Atlantic. J. Mar. Syst. 211, 103449 (2020).

33.
Willis, A. J., Sokal, R. R. & Rohlf, F. J. Introduction to Biostatistics. vol. 72 (Dover Publications, 1988).

34.
Marks, A. D., Kerstetter, D. W., Wyanski, D. M. & Sutton, T. T. Reproductive ecology of dragonfishes (Stomiiformes: Stomiidae) in the Gulf of Mexico. Front. Mar. Sci. 7, 101–105 (2020).
Article  Google Scholar 

35.
Sorell, J. M. et al. Diet and consumption rate of Atlantic bluefin tuna (Thunnus thynnus) in the Strait of Gibraltar. Fish. Res. 188, 112–120 (2017).
Article  Google Scholar 

36.
Varghese, S. P. & Somvanshi, V. S. Feeding ecology and consumption rates of yellowfin tuna Thunnus albacares (Bonnaterre, 1788) in the eastern Arabian Sea. Indian J. Fish. 63, 16–26 (2016).
Article  Google Scholar 

37.
Levins, R. Evolution in changing environments: Some theoretical explorations. (Princeton University Press, Princeton, 1969).

38.
Cresson, P., Ruitton, S., Fontaine, M. F. & Harmelin-Vivien, M. Spatio-temporal variation of suspended and sedimentary organic matter quality in the Bay of Marseilles (NW Mediterranean) assessed by biochemical and isotopic analyses. Mar. Pollut. Bull. 64, 1112–1121 (2012).
CAS  PubMed  Article  PubMed Central  Google Scholar 

39.
Post, D. M. Using Stable Isotopes to estimate trophic postition: Models, methods and assumptions. Ecology 83, 703–718 (2002).
Article  Google Scholar 

40.
Montoya, J. P., Carpenter, E. J. & Capone, D. G. Nitrogen fixation and nitrogen isotope abundances in zooplankton of the oligotrophic North Atlantic. Limnol. Oceanogr. 47, 1617–1628 (2002).
ADS  CAS  Article  Google Scholar 

41.
McCutchan, J. H., Lewis, W. M., Kendall, C. & McGrath, C. C. Variation in trophic shift for stable isotope ratios of carbon, nitrogen, and sulfur. Oikos 102, 378–390 (2003).
CAS  Article  Google Scholar 

42.
Quezada-Romegialli, C., Jackson, A. L. & Harrod, C. Package ‘tRophicPosition’. https://github.com/clquezada/tRophicPosition (2017).

43.
Stock, B. C. & Semmens, B. X. MixSIAR GUI User Manual. Version 3.1. https://github.com/brianstock/MixSIAR (2013) https://doi.org/10.5281/zenodo.56159.

44.
Caut, S., Angulo, E. & Courchamp, F. Caution on isotopic model use for analyses of consumer diet. Can. J. Zool. 86, 438–445 (2008).
CAS  Article  Google Scholar 

45.
Jackson, A. & Parnell, A. Stable Isotope Bayesian Ellipses in R. R package version 2.1.4. 31 https://doi.org/https://doi.org/10.1111/j.1365-2656.2011.01806.x (2019).

46.
Valls, M. et al. Trophic structure of mesopelagic fishes in the western Mediterranean based on stable isotopes of carbon and nitrogen. J. Mar. Syst. 138, 160–170 (2014).
Article  Google Scholar 

47.
Fry, B. Stable Isotope Ecology. (Springer, 2006). doi:https://doi.org/10.1007/0-387-33745-8.

48.
Olivar, M. P., Bode, A., López-Pérez, C., Hulley, P. A. & Hernández-León, S. Trophic position of lanternfishes (Pisces: Myctophidae) of the tropical and equatorial Atlantic estimated using stable isotopes. ICES J. Mar. Sci. 76, 649–661 (2018).
Article  Google Scholar 

49.
Netburn, A. N. & Anthony, K. Dissolved oxygen as a constraint on daytime deep scattering layer depth in the southern California current ecosystem. Deep. Res. Part I 104, 149–158 (2015).
Article  CAS  Google Scholar 

50.
Boswell, K. M. et al. Oceanographic structure and light levels drive patterns of sound scattering layers in a low-latitude oceanic system. Front. Mar. Sci. 7, (2020).

51.
Schott, F. Monsoon response of the Somali Current and associated upwelling. Prog. Oceanogr. 12, 357–381 (1983).
ADS  Article  Google Scholar 

52.
Rosas-Luis, R., Villanueva, R. & Sánchez, P. Trophic habits of the ommastrephid squid Illex coindetii and Todarodes sagittatus in the northwestern Mediterranean Sea. Fish. Res. 152, 21–28 (2014).
Article  Google Scholar 

53.
Silva, G. B., Hazin, H. G., Hazin, F. H. V. & Vaske-Jr, T. Diet composition of bigeye tuna (Thunnus obesus) and yellowfin tuna (Thunnus albacares) caught on aggregated schools in the western equatorial Atlantic Ocean. J. Appl. Ichthyol. 2, 1111–1118 (2019).
Article  Google Scholar 

54.
Gaskett, A. C., Bulman, C., He, X. & Goldsworthy, S. D. Diet composition and guild structure of mesopelagic and bathypelagic fishes near Macquarie Island, Australia New Zeal. J. Mar. Freshw. Res. 35, 469–476 (2001).
Article  Google Scholar 

55.
Laptikhovsky, V. V. A trophic ecology of two grenadier species (Macrouridae, Pisces) in deep waters of the Southwest Atlantic. Deep. Res. Part I 52, 1502–1514 (2005).
ADS  Article  Google Scholar 

56.
González, C., Bruno, I. & Paz, X. Food and feeding of deep-sea redfish (Sebastes mentella Travin) in the North Atlantic. NAFO Sci. Counc. Stud. 10, 89–101 (2000).
Google Scholar 

57.
Clarke, T. A. Feeding habits of stomiatoid fishes from Hawaiian waters. Fish. Bull. 80, 287–304 (1982).
Google Scholar 

58.
Roe, H. S. J. The diel migrations and distributions within a mesopelagic community in the North East Atlantic. 2. Vertical migrations and feeding of mysids and decapod crustacea. Prog. Oceanogr. 13, 269–318 (1984).

59.
Legand, M. & Rivaton, J. Cycles biologiques des poissons mésopélagiques dans l’est de l’océan Indien. Cah. O.R.S.T.O.M., Sér. Océanogr 5, 47–71 (1967).

60.
Suntsov, A. V. & Brodeur, R. D. Trophic ecology of three dominant myctophid species in the northern California Current region. Mar. Ecol. Prog. Ser. 373, 81–96 (2008).
ADS  Article  Google Scholar 

61.
Sutton, T. T., Lancraft, T. M. & Hopkins, T. L. The trophic structure and predation impact of a low latitude midwater fish assemblage. Prog. Oceanogr. 38, 205–239 (1997).
Google Scholar 

62.
Hudson, J. M., Steinberg, D. K., Sutton, T. T., Graves, J. E. & Latour, R. J. Myctophid feeding ecology and carbon transport along the northern Mid-Atlantic Ridge. Deep. Res. Part I 93, 104–116 (2014).
Article  Google Scholar 

63.
Hu, V. J. H. Relationships between vertical migration and diet in four species of euphausiids. Limnol. Oceanogr. 23, 296–306 (1978).
ADS  Article  Google Scholar 

64.
Stefanoudis, P. V. et al. Changes in zooplankton communities from epipelagic to lower mesopelagic waters. Mar. Environ. Res. 146, 1–11 (2019).
CAS  PubMed  Article  Google Scholar 

65.
Aumont, O., Maury, O., Lefort, S. & Bopp, L. Evaluating the potential impacts of the diurnal vertical migration by marine organisms on marine biogeochemistry. Global Biogeochem. Cycles 32, 1622–1643 (2018).
ADS  CAS  Article  Google Scholar 

66.
Kwong, L. & Pakhomov, E. Assessment of active vertical carbon transport: New methodology. Uchenye Zap. Kazan. Univ. Seriya Estestv. Nauk. 159, 492–509 (2017).

67.
Ariza, A., Garijo, J. C., Landeira, J. M., Bordes, F. & Hernández-León, S. Migrant biomass and respiratory carbon flux by zooplankton and micronekton in the subtropical northeast Atlantic Ocean (Canary Islands). Prog. Oceanogr. 134, 330–342 (2015).
ADS  Article  Google Scholar 

68.
Choy, C. A., Portner, E., Iwane, M. & Drazen, J. C. Diets of five important predatory mesopelagic fishes of the central North Pacific. Mar. Ecol. Prog. Ser. 492, 169–184 (2013).
ADS  Article  Google Scholar 

69.
Burd, A. B. et al. Assessing the apparent imbalance between geochemical and biochemical indicators of meso- and bathypelagic biological activity: What the @$#! is wrong with present calculations of carbon budgets?. Deep. Res. Part II 57, 1557–1571 (2010).
Article  CAS  Google Scholar 

70.
Wang, F. et al. Trophic interactions of mesopelagic fishes in the south China Sea illustrated by stable isotopes and fatty acids. Front. Mar. Sci. 5, 1–12 (2019).
ADS  Article  Google Scholar 

71.
Choy, C. A., Popp, B. N., Hannides, C. C. S. & Drazen, J. C. Trophic structure and food resources of epipelagic and mesopelagic fishes in the north Pacific Subtropical Gyre ecosystem inferred from nitrogen isotopic compositions. Limnol. Oceanogr. 60, 1156–1171 (2015).
ADS  Article  Google Scholar 

72.
Henson, S., Le Moigne, F. & Giering, S. Drivers of carbon export efficiency in the global ocean. Global Biogeochem. Cycles 33, 891–903 (2019).
ADS  CAS  PubMed  PubMed Central  Article  Google Scholar 

73.
Boyer, T. P. et al. World Ocean Atlas 2018. NOAA National Centers for Environmental Information. https://accession.nodc.noaa.gov/NCEI-WOA18 (2018).

74.
Williams, A., Koslow, J., Terauds, A. & Haskard, K. Feeding ecology of five fishes from the mid-slope micronekton community off southern Tasmania Australia. Mar. Biol. 139, 1177–1192 (2001).
Article  Google Scholar 

75.
Williams, A. & Koslow, J. A. Species composition, biomass and vertical distribution of micronekton over the mid-slope region off southern Tasmania Australia. Mar. Biol. 130, 259–276 (1997).
Article  Google Scholar 

76.
Sokolov, S. & Rintoul, S. Circulation and water masses of the southwest Pacific: WOCE section P11, Papua New Guinea to Tasmania. J. Mar. Res. 58, 223–268 (2000).
Article  Google Scholar 

77.
Bopp, L. et al. Multiple stressors of ocean ecosystems in the 21st century: Projections with CMIP5 models. Biogeosciences 10, 6225–6245 (2013).
ADS  Article  Google Scholar 

78.
Martínez-García, A. et al. Iron fertilization of the subantarctic ocean during the last ice age. Science 343, 1347–1350 (2014).
ADS  PubMed  Article  CAS  Google Scholar 

79.
Annasawmy, P. et al. Micronekton distributions and assemblages at two shallow seamounts of the south-western Indian Ocean: Insights from acoustics and mesopelagic trawl data. Prog. Oceanogr. 178, 102161 (2019).
Article  Google Scholar 

80.
Jena, B., Sahu, S., Avinash, K. & Swain, D. Observation of oligotrophic gyre variability in the south Indian Ocean: environmental forcing and biological response. Deep. Res. Part I 80, 1–10 (2013).
Google Scholar 

81.
Søiland, H., Budgell, W. P. & Knutsen, O. The physical oceanographic conditions along the Mid-Atlantic Ridge north of the Azores in June–July 2004. Deep. Res. Part II(55), 29–44 (2008).
Article  Google Scholar 

82.
Cook, A. B., Sutton, T. T., Galbraith, J. K. & Vecchione, M. Deep-pelagic (0–3000m) fish assemblage structure over the Mid-Atlantic Ridge in the area of the Charlie-Gibbs Fracture Zone. Deep. Res. Part II 98, 279–291 (2013).
Article  Google Scholar 

83.
Van Utrecht, W. L., Van Utrecht-Cock, C. N. & De Graaf, A. M. J. Growth and seasonal variations in distribution of Chauliodus sloani and C. danae (Pisces) from the mid North Atlantic. Bijdr. Dierkd. 57, 164–182 (1987). More

Record-breaking Turkish diver Şahika Ercümen draws attention to plastic pollution in the Bosporus.Credit: Sebnem Coskun/Anadolu Agency/Getty

Next year sees the start of 12 crucial months for the planet — or at least a proportion of it. Important talks on the future of food and agriculture, biodiversity and climate will all happen in 2021, a year later than planned. But there’s one meeting still missing from this list: the United Nations Ocean Conference, originally due to take place in Lisbon in 2020, has not yet been rescheduled for 2021.
For too long, the ocean and seas, 71% of Earth’s surface, have been under-represented at some of the world’s most influential global environmental-policy processes. That is now changing, helped by a powerful initiative led by 14 world leaders — which this week publishes important findings in Nature. These reports come as the UN, together with many others, is preparing to advocate stronger action. (Researchers, non-governmental organizations and the UN refer to ‘the ocean’ rather than ‘oceans’ to emphasize the connectedness of this global ecosystem.)
Part of the reason ocean policy is neglected is the lack of a high-level intergovernmental process through which binding decisions can be made. The marine environment is discussed when world leaders get together for meetings of the UN conventions on biodiversity and climate — but is rarely, if ever, a priority.

This state of affairs prompted the prime ministers of Norway and Palau — both nations with economies dependent on a healthy ocean — to convene some of their peers, including the leaders of Canada, Indonesia and Kenya. Between them, they agreed to do more to protect and improve ocean health, and to safeguard the benefits that humans reap from the marine environment.
The High Level Panel for a Sustainable Ocean Economy was established in 2018, but its members needed scientific advice. They turned to researchers across ocean sciences and asked them to review the literature on the state of the seas and the benefits they provide, before deciding what further action to take.
This week sees a collection of the researchers’ outputs published in the Nature family of journals (see go.nature.com/3kyd0dx). The reports describe the parlous state of ocean health, but they also provide hope. If the ocean is managed more sustainably, species and ecosystems could revive, and could become better sources of sustainable food, energy, materials, livelihoods and, ultimately, planetary well-being.

As the panel’s research advisers write in a Comment article, climate change is warming and acidifying the ocean and depleting ocean oxygen. At the same time, overfishing is removing important species from the food chain, accelerating biodiversity loss. Unsustainable industrial development along coastlines — new and larger ports, hotels and housing developments — are also adding to ocean pollution. “All of these threats erode the capacity of the ocean to provide nutritious food, jobs, medicines and pharmaceuticals as well as regulate the climate. Women, poor people, Indigenous communities and young people are most affected,” the authors say.
Yet the ocean also has potential to help mitigate climate change. If managed more sustainably, the researchers forecast — in preliminary estimates — it could contribute between 6% and 21% of the emissions reductions needed by 2050 to achieve the goal of the 2015 Paris climate agreement, limiting global warming to 1.5 °C above pre-industrial levels.
The ocean also has the potential to contribute many times more renewable energy than it did in 2018, through increasing offshore wind and wave energy. And it could help to produce more food through cultivation of organisms that are not yet widely consumed, such as molluscs and seaweed.
The political leaders in the high-level panel have said that, by 2025, they will sustainably manage 100% of their ocean areas — not just their national waters, but their entire exclusive economic zones, stretching out 370 kilometres from their coasts. These commitments are commendably direct and rooted in science — and so should be welcomed. But they need to be accompanied by a process to ensure that they can be kept.
Held to account
Pledges made by heads of state are too rarely accompanied by monitoring or accountability mechanisms. Yet it is such things — enshrined in international conventions and law — that ensure world leaders are compelled to report periodically on their progress, or lack of it, in protecting biodiversity, the climate and other areas affected by environmental degradation.

Monitoring and accountability, in turn, need indicators of success or failure. Researchers and national statistics offices are in the process of updating the international standard System of Environmental-Economic Accounting — Experimental Ecosystem Accounting (SEEA EEA), which is due to be adopted by the UN Statistical Commission in March. One of the studies in the collection proposes a framework through which existing global ocean data can be used to measure the condition of ocean ecosystems (E. P. Fenichel et al. Nature Sustain. 3, 889–895; 2020). Indicators on which there is a degree of consensus include those for biodiversity, ecosystem fitness and the ability of the ocean to retain greenhouse gases.
Momentum is building for stronger action. The UN is preparing to publish its second World Ocean Assessment sometime in 2021. Next year will also be the start of the UN’s decade devoted to ocean science and sustainable development. And the UN Convention on Biological Diversity is preparing to update its targets to slow down biodiversity loss — including an updated goal for coastal and marine areas under protection.
It is rare for world leaders to take a lead as the high-level panel has done, and they must be commended for their pledge to manage the ocean sustainably. But governments change. The panel’s members know that, one day, they will need to pass on their responsibilities. In some cases, their successors will want to continue their policies, but in others, they won’t — as we know all too well.
That is why we need a mechanism to monitor pledges according to agreed data, tested by a consensus of the research community. Researchers stand ready to play their part. But to help ensure that these vital pledges are kept, sustainable management of the ocean needs a sustainable system of governance, too. More