Zanzibar’s corals: How Mnemba islanders are restoring their reefs – BBC News

Looking out over the Indian Ocean from Mnemba Island, it is hard to believe that just three years ago the amazing coral reefs surrounding this part of the Zanzibar archipelago in Tanzania were dying.

Under the threat of climate change, overfishing and other human activities, the islanders faced the loss of their lives and the prospect of permanent displacement.

Desperate to save the colorful, oval-shaped rocks that are right next to the shore and about 7 kilometers (4.3 miles) long, communities on the small island have embraced a conservation project that has managed to restore some of what was lost.

The plan also aims to protect the reef, which is known around the world for its beauty, in other ways.

The water is so clear that the rocks, which are 10m (32ft) below the surface, are visible within touching distance.

But a few years ago locals began to notice how corals were being stressed – part of this was due to climate change, which has warmed the sea.

Coral may look like a plant, but it’s actually a type of animal – actually lots of tiny creatures called polyps. They grow very slowly and form a hard outer shell by extracting salt from the sea water, then they join together to form what are called colonies.

Reefs are sometimes referred to as “marine rainforests” because they form ecosystems that support a wide variety of marine life.

But when the water heats up a few degrees more than normal, it causes the corals to expel the brightly colored algae that live inside and provide nutrients. When the algae leave, the coral fades, bleaches and eventually dies.

Gunpowder used by fishermen has also been killing corals, along with the abundance of uncontrolled tourist boats and divers causing damage to the reefs.

A fish trader from Mnemba Island, Juma Mshindan says that it was found that there is something wrong: “There is a big difference in the availability of fish in the past compared to now. In the past, there were many fish.”

Sustainable tourism group &Beyond and non-profit organization Africa Foundation began working with islanders in September 2021 to help address some of these issues.

Underwater nurseries were created using metal mesh tables, where pieces of coral are planted to be replanted on coral reefs.

They are cared for and raised by local divers who are trained as conservation guards.

It takes about two or three months for a coral colony to form and then the keepers take them to the reef.

The results so far are encouraging, with 80% of the cover restored to the so-called “house reefs” that surround the island.

“It’s like they’ve grown on their own,” says curator Hajja Uledi.

“We’ve put the rock back, and you can’t tell the difference. Now they have fish around. The work is good, and many species can be seen.”

Conservationists also created artificial reefs – steel and stone structures that were placed about 3 km from the island and where conservationists also plant newly grown corals from nurseries.

These are intended to help replenish marine life – which benefits fishermen and has also become an attraction for divers and divers.

Dr Camilla Floros, senior scientist at the Africa Foundation’s Oceans Without Borders programme, says the ongoing restoration program is careful to work with the right materials – learning from past mistakes around the world.

“When artificial reefs were in their infancy, people used the wrong materials like tires to try to create them, which is not the right way,” he says.

The success of the regeneration work in Mnemba Island is due to the support of the local community, Dr. Floros admits.

“Whenever we have a new plan, we discuss it with them, and we get their space,” he says.

Atuwa Omar is one resident of the area who has been involved in the restoration. Before taking up a position as a park ranger, the 24-year-old was at home taking care of her young son.

“Being a ranger in this Mnemba Island project not only enables me to feed my family but also helps my son’s education,” he says.

Although Ms Omar admits it was not easy for her, as she is the only woman working in the project.

She has faced conservative views from some who don’t want women involved – but she says such challenges have been worth it.

Conservation groups have been working side by side with local governments and the sea surrounding Mnemba was designated as a protected area by the government of Zanzibar, part of independent Tanzania, in 2022.

This means that action can now be taken to reduce the damage caused by tourists and fishermen.

Coordinator of Africa Foundation Zanzibar, Bakari Jaha showing the number of tourists who were visiting the house rocks.

“In the past, the area faced a lot of pressure from tourism, with 200 boats carrying at least 400 guests entering an area of ​​only 200 square meters,” he says.

“To preserve the area, the government, along with &Beyond and the African Foundation, decided to limit the number of visitors to 80.”

Previously, visitors were charged $3 (£2.40) – this cost has now been increased to $25.

“This approach has not only enhanced environmental conservation but also increased income,” says Mr Jaha.

Fishing has also been suspended around the house reef as it is being restored.

“We have seen positive changes. Illegal activities such as the use of gunpowder have decreased and fishermen have had enough understanding about sustainable fishing methods,” says Mshenga Ally, a fisherman.

The government of Zanzibar says it is very encouraged by the success of the Mnemba restoration project, it is looking to expand it to other threatened areas.

“The government has identified 14 areas with intact reefs and others with damaged corals and we plan to preserve them,” says Dr. Makame Omar Makame, Director of the Zanzibar Marine Department.

“We have placed buoys so that people will be careful, understanding that fishing activities are not allowed in that place.”

The pressures on Zanzibar’s reefs mirror the threats facing coral reefs around the world. Those involved with the Mnemba project say, while they cannot stop the currents of warm ocean water, they hope their efforts will be able to help other areas that face the threat.

“The relationship between the ocean and the coral is important for the health of the ocean. We have witnessed corals being regenerated, even in the deep,” says Mr Jaha.

“We’re allowing ocean conditions to restore the reef to its natural state.”