EN FR

New paper by researchers in Module G published in Nature Communications

Unless global greenhouse gas emissions are reduced, loss of marine life will pose new challenges for fisheries and sustainable development, especially in some of the world’s least developed countries.
 
An article published in the international journal Nature Communications on May 6 reveals that, if left unchecked, climate change will cause widespread reductions in marine animal abundance throughout the world over the next 80 years, with disproportionate effects on coastal developing nations.
 
"While developing countries have contributed the least to climate change, they are projected to suffer the most from climate-driven impacts on their marine ecosystems,” says lead author Daniel Boyce, a marine ecologist and research fellow at the Ocean Frontier Institute at Dalhousie University.  “At the same time, they stand to benefit the most from reduced emissions."
 
The team of scientists from the Ocean Frontier Institute (OFI) and the Université du Québec à Montreal reached the conclusion using a combination of state-of-the-art global models. The study evaluated changes to the year 2100 under two contrasting warming scenarios – one that tracks our current trajectory with emissions continually increasing, and the other with strong reductions as per the Paris Agreement. The authors report that under the continuing emissions scenario, significant changes in animal biomass would occur across 57% of the global ocean, 84% of which would experience a decline.
 
"Widespread declines in marine life will undoubtedly have widespread consequences for the welfare of all other species, including us," says Dr. Boyce.
 
The authors found a striking pattern: future biomass changes were significantly associated with the current global geographic patterns of socio-economic status, fisheries production and human stressors.
 
“We found that animal declines were typically more severe within the marine waters of developing nations – parts of the world that often face many additional challenges, such as malnutrition, poverty, low adaptive capacities, and high reliance on fisheries. Yet these developing nations have also contributed the least to historic CO2 emissions,” says co-author Derek Tittensor, Jarislowsky Chair in Marine Ecosystem Forecasting at Dalhousie University.
 
The largest biomass losses were also projected in locations that presently support the highest fishery catches, a sign that widespread disruptions of the fishing sectors are likely. Concerningly, the authors also reported that the largest declines would occur where additional stressors, such as pollution, are highest. Since these stressors are not included in the models, the authors believe that their projected declines actually underestimate the full extent of future change.
 
Overall, the study warns of the potentially severe consequences of continued greenhouse gas emissions, while stressing the near-universal benefits of mitigation.
 
"Our study paints two very contrasting pictures of how a future ocean might look, and it's up to us to decide which future we want. Reducing emissions offers the most straightforward means to avoid the widespread losses of animal life, and associated socio-economic consequences, that may unfold if greenhouse gas emissions continue at pace,” says Dr. Boyce.
 
This paper is among the first results to come from 23 large research projects funded by the Canadian First Research Excellence Fund via the OFI -- a collaborative hub for ocean research created in 2016 to bring together the brightest scientific minds to tackle the most pressing issues facing the ocean. The co-authors of this paper have been working together under one large research project called Future Proofing Marine Protected Area Networks. More significant papers are expected as the research continues.
 
“This is exactly the kind of impactful work that the OFI was created for,” says Dr. Anya Waite, OFI’s Scientific Director. “This is scientific proof that if we act globally now, we can change the future of some of the world’s most vulnerable areas.”
 
The study was the result of a multi-year effort made possible through global collaboration of climate and ecosystem modellers as part of the Fisheries and Marine Ecosystem Model Intercomparison Project (FishMIP; www.fishmip.org/).