Mitigating Overfishing in Southwest Madagascar Through Low-Cost Artificial Reefs

Project offers hope to fisherfolk dealing with declining yields while also serving as a viable conservation tool.

Madagascar’s vast 5,000 km coastline, 450 km barrier reef, and 250 islands provide an expanse of productive habitats for marine life. The Bay of Ranobe in southwest Madagascar is a shallow lagoon protected by a 32 km barrier reef that contains coral reefs, mangrove forest, and seagrass beds. These biodiverse and productive waters support more than 20,000 artisanal fishers who use these sheltered waters to fish. As a traditional fishing community, the Vezo (imperative of the verb “mive” in Malagasy which means “to row”) are culturally linked to the ocean. These coastal communities are specialist marine foragers and depend on the marine environment for survival.

photo of coral reefs
The productive waters of the Bay of Ranobe in Madagascar support some 20,000 small-scale fishers. Drought, growing local demand for fish, and use of destructive fishing practices are all compromising the health of the bay. Photo by Brandon Swan.

For decades, the Vezo thrived in their remote coastal habitat; fishing with wooden pirogues and using home-made fishing gears. Today, however, the growing demand for food security from an ever-expanding population is stripping these once productive waters and putting into jeopardy the future of these coastal communities. Consecutive years of severe drought have resulted in poor agricultural yields and a subsequent significant influx of people from inland communities to the bay looking for new means of livelihood. The majority of these new arrivals have little to no fishing knowledge and use destructive fishing practices such as mosquito nets and beach seines. Habitat degradation, declining fishery yields, and increased competition for marine resources is driving a pattern of over-exploitation and ecosystem collapse, compromising marine resource availability for Vezo fishermen. This has become a significant issue throughout the region, driving up poverty levels and famine.

Vezo communities are now looking for sustainable solutions to address this social and natural crisis. There is an urgent need to rethink how best to reconcile nature conservation with sustainable development, and enhance community resilience and adaptive capacity to climate change. Progressive management approaches need to be developed such as habitat-based enhancements, restoration of damaged habitat, complex habitat development through artificial reef structures to increase survival and primary productivity, and securing biodiversity to ensure natural systems have the productive capacity to satisfy the demands of rapidly expanding indigenous coastal communities.

International NGOs, along with local universities and community groups, are now working together to preserve coastal environments and marine resources in the region. In the fishing village of Ifaty, Bruno Keza Souvenir, the president of the local association of fishermen, FIkambanana MIaro sy HAnasoa ny RAnomasina (Association to Protect and Enhance the Marine Environment) or FIMIHARA, has been busy promoting a new type of fish refuge in the form of an artificial reef.

Like the majority of people in the Bay of Ranobe, over his lifetime Souvenir has witnessed first-hand the dramatic decline of marine resources and habitats, along with an increase in unsustainable and destructive fishing practices. According to Souvenir, about 30 years ago, there used to be an abundance of fish throughout the bay and catches among all villages were bountiful. But nowadays people struggle to feed their families because fish and invertebrates are decreasing not only in abundance, but also in size. Over the last few years, fishermen have been forced to venture further out to sea and use more destructive gear in order to catch enough fish for daily sustenance.

photo of artificial reef building project
Community members put together so-called octopus pots for an artificial reef. Photo by Margot Chapon.

Now, a new artificial reef project in the bay is offering hope to the fisherfolk while also serving as a viable conservation tool. Artificial reefs are man-made structures that are placed in the water in order to promote marine life or to control erosion. They were first designed by Japanese fishermen 200 years ago in order to increase fishing resources through the creation of alternative habitats. Artificial reefs can deliver significant ecological and economic benefits, and have the potential to address food insecurity and poverty in many coastal countries.

In 2016, Reef Doctor, a local conservation and social development NGO that has been working with local communities in the region for over 15 years, developed plans for an artificial reef in collaboration with FIMIHARA in the Bay of Ranobe. Using low cost materials, like limestone rock and cement cylinders, and methods that are easily replicable by local fishing communities, and with sheer determination, Reef Doctor and the local community have been able to successfully build a functioning fish refuge in the bay. By creating a complex structure, with cavities forming shelters and hard calcareous stones a biotic settlement substrate, this artificial reef forms an ideal refuge for fish and also encourages coral settlement.

Installation of the artificial reef required a team effort from Reef Doctor (international conservationists and volunteers), FIMIHARA, and local fishermen. Artificial reef materials were delivered to the site via pirogues and installed on the seabed by scuba divers and local freediving fishermen. With their fins removed and laden with extra weight, the divers could construct the new dome-shaped reefs out of limestone boulders in a manner similar to walking on the moon. Once the initial reef framework was established, cement cylinders and octopus pots were added to enhance the habitat complexity even further.

photo of artificial reef building project
Scubadivers construct the base for an artificial reef using limestone boulders. Photo by Sebastien Boudry.

After one year of construction, the artificial reef was opened as an alternative fishing area for several villages to access, representing several thousands of people. The site, called “Vato Mahavelo” by the Vezo fishers, meaning “the rocks that give life,” not only provides a new habitat to attract marine life, but also reduces the fishing pressure on surrounding overfished marine habitats.

Prior to this project, artificial reefs were completely unknown to the majority of local villagers. As such, one of the most challenging aspects was to ensure that the local people understood, accepted, and respected the use of artificial habitats. To address this, awareness-raising meetings were conducted in the community, and a traditional ceremony was held to appease the ancestors and commence the opening of the artificial reef building project.

FIMIHARA and Reef Doctor continuously monitor the artificial reef to observe the ecological effects and have already seen an increase in fish diversity and abundance, especially among juvenile reef fish and invertebrates. The hope is that this will translate into increased in fish yields, the ultimate goal of this project. Primary evidence suggests that the artificial reef is increasing local fish populations and should thereby reduce unsustainable fishing practices. For Souvenir, projects that support sustainable fisheries in the bay are essential in order for future generations to survive.

This community-based project offers a practical, reproducible, and culturally sensitive solution for simultaneously protecting marine resources and improving the wellbeing of coastal communities. Last year, Reef Doctor’s head science officer, Roberto Komeno, was awarded the prestigious 2018 CORAL Conservation Prize by the Coral Reef Alliance for his work on this project. A second artificial reef has now been implemented in the bay, funded by the Waitt Foundation Rapid Ocean Conservation Grants Program, and three reefs more have been established further south, near Anakao with the villages of Beheloke, Besambay, and Tariboly, in partnership with the World Wildlife Fund. The plan now is to expand the project further across the Bay of Ranobe. It is hoped that the creation of a network of productive alternative artificial fishing habitats will secure Vezo livelihoods whilst providing vital respite for overfished and heavily degraded natural reef habitats in the bay.

See a short film about the role low-cost artificial reefs can play in addressing over-fishing impacting traditional Vezo fishing communities in southwest Madagascar below:

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