Let more big fish sink: Fisheries prevent blue carbon sequestration—half in unprofitable areas
|Author(s)||Mariani Gaël1, Cheung William W. L.2, Lyet Arnaud3, Sala Enric4, Mayorga Juan4, 5, Velez Laure1, Gaines Steven D.6, Dejean Tony7, Troussellier Marc1, Mouillot David1, 8|
|Affiliation(s)||1 : MARBEC, Univ Montpellier, CNRS, IFREMER, IRD, Montpellier, France.
2 : Changing Ocean Research Unit, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, BC, Canada.
3 : World Wildlife Fund, Washington, DC 20037, USA.
4 : National Geographic Society, Washington, DC 20036, USA.
5 : University of California, Santa Barbara, Santa Barbara, CA 93106, USA.
6 : Bren School of Environmental Science and Management, University of California, Santa Barbara, CA 93106, USA.
7 : SPYGEN, 17 rue du Lac Saint-André, Savoie Technolac, Le Bourget du Lac, France.
8 : Institut Universitaire de France, Paris, France.
|Source||Science Advances (2375-2548) (American Association for the Advancement of Science (AAAS)), 2020-10 , Vol. 6 , N. 44 , P. eabb4848 (9p.)|
Contrary to most terrestrial organisms, which release their carbon into the atmosphere after death, carcasses of large marine fish sink and sequester carbon in the deep ocean. Yet, fisheries have extracted a massive amount of this “blue carbon,” contributing to additional atmospheric CO2 emissions. Here, we used historical catches and fuel consumption to show that ocean fisheries have released a minimum of 0.73 billion metric tons of CO2 (GtCO2) in the atmosphere since 1950. Globally, 43.5% of the blue carbon extracted by fisheries in the high seas comes from areas that would be economically unprofitable without subsidies. Limiting blue carbon extraction by fisheries, particularly on unprofitable areas, would reduce CO2 emissions by burning less fuel and reactivating a natural carbon pump through the rebuilding of fish stocks and the increase of carcasses deadfall.