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Mangrove deforestation in Madagascar: What are the options?

The last time you heard from us at Blue Ventures, my colleague Garth Cripps was talking about shark fishing on Madagascar’s west coast.  Here Dr. Trevor Jones, our Blue Carbon Science guru, talks about his favorite coastal ecosystem, mangrove forests, and some of the ways we’re looking to partner with communities for their conservation. Take...

The last time you heard from us at Blue Ventures, my colleague Garth Cripps was talking about shark fishing on Madagascar’s west coast.  Here Dr. Trevor Jones, our Blue Carbon Science guru, talks about his favorite coastal ecosystem, mangrove forests, and some of the ways we’re looking to partner with communities for their conservation. Take it away Trevor!

The island nation of Madagascar has long captured the world’s curiosity and is renowned for its unparalleled biodiversity, magnificent landscapes and unique culture. In the northwestern coastal Ambaro-Ambanja bays region, you will encounter mountains transitioning into lowlands littered with lush agro-forest mosaics producing vanilla, cacao, coffee and a cornucopia of fruits – output that would be impossible on the arid lands found further south.  These lush landscapes reach right to the coast where they meet postcard perfect white sand beaches and turquoise waters, but also vast, dense mangrove swamps. 

It was during my first trip here in February 2012 that I initially experienced the diversity of these vast and fascinating coastal ecosystems, but also their rapid decline.  Clambering down a steep bank, transitioning from agro-forest to mangrove, I recall taking my first steps into what remained of a mangrove forest that had been clear-cut; sinking deeply into the muddy soil as I was confronted by a sweeping panorama of stumps.

Photo: mangroves in Mahajamba Bay, Madagascar
A healthy mangrove forest in Mahajamba Bay, northwest Madagascar (Photography by Garth Cripps)

Madagascar contains about 2% of the world’s mangroves, Africa’s fourth largest extent behind Nigeria, Guinea Bissau and Mozambique. These marine (or “blue”) forests are critical to the coastal communities who live in and around them, providing food, cooking fuel, and construction materials for boats and houses, as well as medicine.

What’s more, intact mangroves protect the land from storm damage and coastal erosion, filter the water and a growing number of  studies show they are amongst the most carbon-dense forests on the planet – meaning they are vital in mitigating the effects of climate change!

Coastal communities throughout Madagascar have depended on mangroves for thousands of years, however a rapidly growing population, poor governance and encroachment by urban areas have led to their destruction through over-harvesting for timber and charcoal and conversion to agriculture and aquaculture.

Analysis by Blue Ventures of maps produced by Chandra Giri and colleagues suggest that Madagascar lost a staggering 21% (57,000 hectares) of her mangroves between 1990 and 2010, meaning annual national losses of more than 1%. While natural processes, such as forest succession and cyclones, surely caused part of this loss, our time on the ground has confirmed that it was and is increasingly resulting from human activities driven by poverty and a lack of alternatives.

Photo: Degraded mangrove forest Madagascar
An area of degraded mangrove forest in Ambanja Bay, northwest Madagascar (Photography by Trevor Jones)

Our research in Ambanja and Ambaro bays, shows a loss of 1,800 hectares of mangrove forest, equivalent to 3,364 American football fields. This loss at the very least compromises many important ecosystem goods and services, and at worse sees them vanish completely.

Beyond the direct impact on local communities, there is potentially a far-reaching ripple effect which could impact the surrounding coastal ecosystems as well as releasing substantial greenhouse gases into the atmosphere.

While there are many potential strategies to prevent this continual deforestation, all have their own challenges and shortcomings and are yet to proven effective in the long-term. One route is to place a monetary value on mangrove ecosystem services, through market-based carbon finance mechanisms such as REDD+.

However, there are many sceptics of these carbon finance programs, and the critics are not without their reasons. Nor is the concept of “selling nature to save it” feasible without first addressing several key issues.  One must consider traditional user rights, what the equitable cost will be, as well as benefit sharing.

A project must also avoid what is known as “leakage”- protecting one area while simply shifting the deforestation somewhere else.

Further complicating matters for a blue carbon project is the fact that approved carbon accounting methodologies were originally designed for terrestrial forests, not mangroves. The exact nature of natural mangrove dynamics and carbon fluxes, as well as the impacts of climate change on these forests, remain areas of ongoing research.  While certainly warranting continued investigation, the viability, appropriateness and success of mangrove carbon projects have yet to be established.

Since mangrove ecosystems have such diverse ecological and cultural values, and carbon projects remain uncertain, carbon sequestration is but one of the many ecosystem services for which payments can be explored. However, as with carbon, monetizing any ecosystem service has to be a consensual, community-centered endeavour, and needs to acknowledge the holistic interconnectedness and value of that ecosystem and all of its services.

The challenges and costs of developing other, non-carbon payments for ecosystem services (PES) are no less diverse. The potential outcomes can also be negative, and include perverse incentives and preference towards certain services over others and an erosion of existing conservation traditions.

Photo: community-based monitoring
A Blue Ventures technician teaches community-based monitors how to use a GPS device (Photography by Garth Cripps)

Since 2008, we’ve been working with coastal communities, NGO partners including WWF and HONKO, and researchers from the University of Antananarivo’s Water and Forestry Department and the University of Toliara’s Marine Science Institute, to evaluate and work towards establishing community-based mangrove REDD+ and other PES projects. Including Ambaro and Ambanja bays, these efforts are ongoing in four coastal locations and are helping increase the awareness of the immense and diverse value of blue forests.

Beyond hard carbon science, central to our Blue Forests Project is also examining the socioeconomic importance of natural resource-use and the potential impacts on livelihoods and biodiversity of mangrove REDD+ activities.

Coastal communities in Madagascar and other impoverished tropical nations have and continue to come up with feasible, practicable conservation approaches. Even though the full benefits of services provided by healthy, intact mangrove ecosystems are not yet fully understood, recognizing their true economic value may be the only way to strengthen and further spread an existing appreciation for these ecosystems.

To this end, education and awareness strategies are also critical. Increasing stakeholder awareness about the intrinsic value of mangroves can go a long way in garnering support for long term community-based resource management.

Ultimately, whether it is short-term funding from non-carbon PES such as temporary mangrove closures, or long-term funding from carbon financing, our Blue Forests Project aims to help empower coastal communities through consensual, community-driven conservation.

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