Fish communities can contribute simultaneously to nature and human populations in tropical reefs

[Press release] - Published on October 18, 2024 in Press Corner, Science-Society

Por the first time, an international team led by researchers from the University of Montpellier, CNRS and FRB has estimated 29 contributions of reef fish communities to human needs and the proper functioning of tropical coastal ecosystems worldwide. Their work, published in the journal One Earth by a PhD student at the University, is part of the Nature Futures Framework which proposes imagining desirable futures where humans and nature can coexist sustainably. Within this framework, this work has estimated the potential contributions of nature to itself, called "Nature for Nature", as well as the contributions of nature to human beings called "Nature for People", which are not mutually exclusive.

A major undertaking

This work is the culmination of an international collaboration ( Biodiversa+ REEF-FUTURES project, where 1237 reefs are studied worldwide including over 1000 fish species) and by the wide range of contributions documented (29 contributions are estimated). These range from the concentration of fish micronutrients and their aesthetic appeal, to the diversity of ecological roles played by fish within reefs. Fish community contributions are calculated on the basis of the abundance of each species on the reefs, data collected during dives using the participatory science protocol Reef Life Survey participatory science protocol deployed worldwide for over 18 years. 

This work thus distinguishes four situations where each of the "Nature for Nature" and "Nature for People" dimensions can be strong or weak. For example, the reefs of the Galapagos Islands can mainly contribute to the proper functioning of reefs, thanks to their ecological originality and unique evolutionary history. Reef fish in French Polynesia, on the other hand, provide benefits to both reef ecosystems and humans, thanks to their high diversity, high biomass and aesthetic appeal, enabling both local fishing and tourist attraction. In contrast, fish communities in Tanzania are heavily exploited by humans, and no longer make a significant contribution to the proper functioning of coastal marine ecosystems. 

Some fish communities can therefore be ecologically healthy while also being able to provide significant benefits to human populations, challenging the conventional view that conservation strategies should privilege one over the other. These findings pave the way for interdisciplinary, participatory approaches involving ecologists, social scientists and policy-makers, to optimize the management of these vulnerable ecosystems to meet both human needs and conservation objectives. Only this strategy will enable us to build a more desirable future where nature and humans can coexist in a sustainable manner. This work also raises the challenges of restoring reefs that have been severely degraded and/or excessively impacted by human exploitation. 

As the French government intends to make 2025 the Year of the Ocean in France, culminating in the organization of the^3rd United Nations Ocean Conference in Nice, this article illustrates the scope of these challenges, the possible scenarios and the opportunities linked to coexistence between human populations and reef fish, which are emblematic and particularly affected by human activities. More generally, this work opens up original avenues and a methodology that can also be applied to terrestrial ecosystems, and is therefore of interest beyond that of coastal marine ecosystems.

Reef fish play a vital role in the food chain and contribute to the health of reefs by controlling algae populations and helping to circulate nutrients. They also contribute to human activities, stimulating the local economy through tourism and fishing. Photo: Ningaloo Reef is a coral reef off the west coast of Australia. Rick Stuart Smith

Joshua Cinner, Professor at the University of Sydney (Australia): "One of the most interesting aspects of this article is that it identifies real 'hot spots', where reefs offer benefits to both man and nature."

David Mouillot , Professor at the University of Montpellier (France): "As leader of the international REEF-FUTURES project (Biodiversa+), in which we have put a lot of effort into estimating these multiple contributions of reef fish, I see this synthesis as a culmination but also a hope to implement nature-based solutions, which draw inspiration from local examples, to pull certain tropical coastal socio-ecosystems out of their negative trajectories." 

Nicolas Mouquet, CNRS researcher and Scientific Director of the FRB's Centre de synthèse et d'analyse sur la biodiversité (Cesab) in Montpellier: "Our work paves the way for addressing the essential trade-offs between ecological integrity and human well-being. By moving beyond traditional models of economic growth and adopting a post-growth approach, I believe we can truly foster sustainable coexistence between biodiversity and humanity."

Rick Stuart Smith, Professor at the University of Tasmania (Australia): "Reef fish are extraordinarily important to the functioning of marine ecosystems and provide many benefits to human societies. I'm sure that the general public doesn't appreciate just how diverse these contributions are, and I even think that the scientific community underestimates them. For me, this study represents one of the most comprehensive accounts of the diversity of roles played by reef fish."

Key words : Ecology, Environment, Research, Science