A sustainable marine economy may not be possible in Tanzania without cutting global CO2 emissions

Balancing economic growth alongside environmental protection is a key challenge for global ocean management. This is particularly true in Global South nations, such as Tanzania, where climate-driven ocean change requires robust and adaptive marine spatial planning (MSP) and a thorough understanding of the likely trade-offs, to ensure continued and effective conservation measures whilst still providing marine resources for the people that rely on them.

What is Marine Spatial Planning?

Marine Spatial Planning (MSP) is a public process of analysing and allocating the distribution of human activities over space and time in marine areas to achieve ecological, economic and social objectives that are usually specified through a political process.

Tanzania has a coastline that stretches over 800 miles along the western shore of the Indian Ocean, harbouring unique biodiversity and representing a life-sustaining resource, not only for coastal communities but also the wider population.

Fish from small-scale fisheries nourish nearly 35 million people in Tanzania (72% of the population) and play a critical role in Tanzania’s progress towards the Sustainable Development Goals (SDGs), to transform the food system and promote healthy diets alongside a sustainable environment. The country also relies on the marine environment for other livelihoods, such as eco-tourism and its commercial production of seaweeds for the global market; an activity that is predominantly undertaken by women and offers one of the few opportunities for economic independence for women.

Tanzania is in the process of developing marine spatial plans with various planning processes taking shape across the country, in partnership with the Indian Ocean Rim Association (IORA) and the Nairobi Convention. The multi-faceted challenge of addressing community, conservation and wider economic needs requires a comprehensive understanding of the environment, stakeholders and sectors involved, expert analysis and sensitive consideration, all under the umbrella of a changing climate.

Led by scientists from Plymouth Marine Laboratory and the Tanzanian research institutions of Tanzania Fisheries Research Institute (TAFIRI) and the University of Dar es Salaam, the study used state-of-the-art MSP meta-analysis of ocean climate modelling to estimate climate-driven changes in ecosystems that underpin conservation efforts, artisanal fishing and seaweed farming, for the entire Tanzanian marine ecosystem. The team also employed participatory mapping exercises to explore the perception of ongoing climate-driven changes in the study area.

As climate change unfolds in different ways in different areas, regional oceanographic processes can lead to medium-term trends in climate variables that allow for climate-resilient areas. In other areas, localised trends could occur that may not necessarily be consistent with the long-term climate change trends. These two types of areas, known as climate change refugia and bright spots, may be harnessed towards the delivery of sustainable ocean management, and capitalised upon within shorter time frames, as a time-buying strategy for people and ecosystems.

The team estimated environmental changes within the next 20 and 40 years, and long-term climate change trends combined with increasing extreme weather present important challenges to the activities of the study’s target sectors of conservation, artisanal fishing and seaweed farming, locally and regionally.

Only a few areas exhibited climate resilience and opportunities for sectoral expansion under increasing emissions, but these areas could be crucial for communities and livelihoods in Tanzania in the short term. Coastal areas north of Unguja/Zanzibar Island appear to be more resilient to climate change, and compensatory mechanisms across the foodweb may lead to an overall stability in the targeted fish community over time, especially offshore. However, the community structure may change as more climate-resilient species thrive and become dominant.

It is envisaged that this research will help inform spatial management strategies for these coastal and marine areas, that may lead to sustainable ‘blue’ economic, social and environmental growth, despite increasing climate-change pressures.

Including these climate change refugia and bright spots in effective ocean management strategies may serve as nature-based solutions in promoting adaptive capacity for some of Tanzania’s most vulnerable economic sectors; creating wage-gaining opportunities that promote gender parity, and delivering some economic benefits of a thriving ocean where possible.

Prof. Ana Queirós, Marine and Climate Change Ecologist at Plymouth Marine Laboratory (PML) and lead author on the study, said:

“Without curbs in global emissions, a bleak future may emerge for the globally valuable biodiversity hosted in Tanzania, and for its coastal communities, despite the expansion of protected areas or curbs in other pressures.”

“Growing a sustainable ocean economy in this part of the Global South remains a substantial challenge without global decarbonisation. Tanzania ranks 103rd with a mere 0.03 % of the total global emissions share. As this study shows, growing emissions (depicted by emissions trajectory RCP8.5) represent substantial challenges to the sustainability of Tanzania’s marine protected species and habitats, its artisanal pelagic fishing sector and its seaweed farming sector.

As such, growing global emissions threaten the growth of Tanzania’s blue economy, the delivery of 2050 Africa’s Maritime Strategy, as well as the country’s commitments to the United Nations 2030 Agenda for Sustainable Development. There is recognised inequality between high emissions producing countries and those that bear the brunt of the impacts of climate change, and our analysis supports that this is also the case for Tanzania”.

Dr Narriman Jiddawi, co-author on the paper from the University of Dar es Salaam (Tanzania) and member of the Women in Marine Sciences network (WIMS) of the Western Indian Ocean Marine Science Association (WIOMSA), commented:

“The blue economy is a new initiative in Tanzania.  However, sustainable development commitments and achievement of such efforts have been constrained by various factors such as inadequate environmental management awareness among key stakeholders, insufficient resources to adequately address blue economy and environmental issues as well as lack of efficient and effective alternative sources of energy to reduce dependency of forest resources as the main source of energy.. Awareness raising among the local communities regarding blue economy and environmental management is thus of crucial importance  to contribute in the achievements of this sector”.

Dr Modesta Medard, co-author on the paper and Coordinator for the Marine Programme at WWF Tanzania, added:

“The study is very relevant for us in answering various critical questions relating to the Blue Economy agenda and our coastal communities in Tanzania”.

This work was funded by the Global Challenges Research Fund through UK Research & Innovation SOLSTICE-WIO project, UK Natural Environment Research MSPACE project and the European Commission’s Horizon 2020 FutureMARES project. The study partners were Plymouth Marine Laboratory (UK), Zanzibar Seaweed Cluster Initiative (Tanzania), Tanzania Fisheries Research Institute (Tanzania), University of Dar es Salaam (Tanzania), Lake Vitoria Fisheries Organization (Tanzania), National Environment Management Council (Tanzania), National Oceanography Centre (UK), Finnish Environment Institute (Finland), Coastal Oceans Research and Development (Kenya), Rhodes University (South Africa) AZTI Marine Research (Spain), Mercator Océan International (France), WWF (Tanzania), University of Exeter (UK), University of Liverpool (UK).