On the picturesque shores as you approach Pate from Lamu Island, you are met by a series of floating cages bobbing gently on the water's surface near a patch of mangrove forest.

Here, amid the rhythmic ebb and flow of the ocean, a group of youth tend the cages. These cages house large crabs at different stages of growth and the youth’s sole duty is to ensure that the crabs attain the market-ready weight, through a specialised feeding regimen designed to grow them in size and weight to meet some special market requirements.

These crustaceans are not merely held in captivity but nurtured and fattened with care, transforming them into a prized commodity sought after by discerning buyers for export.

Swaleh Abdalla, one of the people in charge of the crab-fattening project, says ultimately, their aim to establish ecotourism in the island.

“Our goal is to nurture the crabs for our own ecotourism venture, which we are in the process of developing,” says the 30-year-old.

Swaleh Abdallah of Prati attending to mud crabs, part of community livelihood. PHOTO | POOL

Read: Low tide for local fishermen as trawlers harvest in high seas

The venture, Pate Resources and Tourism Initiative (Prati), is in its infancy, having started only last September, and with a current capacity of 200 units to accommodate the crabs.

The crab project is funded by Wetlands International, a body involved in the conservation and restoration of wetlands.

The project is already playing a pivotal role in the intricate tapestry of coastal livelihoods. It serves not only as a vital consolidation centre and a fresh source of income for the local fisher folk — who sell their daily catch to the young men for feeding — but also as a critical resource in preserving the mangrove ecosystem.

Crabs and mangroves share a symbiotic relationship. The crab-fattening hub transcends mere economic transactions, embodying the resilience and resourcefulness of coastal ecosystems. It serves as a testament to the interconnectedness of habitats and species, showcasing the relationships within the natural environment.

Mangrove forests

“As long as our mangrove forests remain healthy and intact, our supply of crabs will continue to flourish. However, if we degrade our mangroves, we risk losing this vital resource that the crabs solely rely on for procreation and survival. Thus, the conservation of mangrove forests is paramount to ensuring the sustained abundance of crabs and other fish species in our coastal regions,” Mr Abdalla says.

Nestled on a rocky promontory, Pate, situated on Kenya's northern Indian Ocean coastline, is cradled by the evergreen mangrove forests of Lamu County.

The mangroves in Lamu form the cornerstone of sustenance for Pate and other islands, guaranteeing residents a reliable supply of food, and supporting livelihoods.

Beyond crabs, mangroves play a crucial role in supporting diverse fish populations. They serve as invaluable breeding grounds for fish and crabs, providing an optimal environment for the reproduction, early development and abundant food sources for fish and crabs alike.

This contributes to the productivity and resilience of these coastal ecosystems.

Read: Pollution choking aquatic life, pushing fishers out of business

“The intricate root systems of mangrove trees offer shelter and protection for fish eggs, shielding them from predators and strong currents,” says Shawlet Cherono, project officer at Wetlands International, Kenya.

“Additionally, the dense canopy of mangrove foliage helps to regulate water temperature and provide a steady supply of organic matter, creating ideal conditions for fish larvae to thrive. The degradation of mangroves has led to the reduction of fish in the ocean.”

She says that protecting and preserving mangrove habitats is essential for ensuring abundance of fish species and sustaining the livelihoods of coastal communities that depend on them.

In return, crabs play a vital role in the mangrove ecosystem by aiding in nutrient cycling, sediment stabilisation, and enhancing soil aeration through their burrowing activities.

This mutualistic relationship highlights the interconnectedness of marine life and underscores the importance of preserving both mangrove forests and crab populations for the overall health of coastal environments.

At the Prati crab-fattening hub, the process is meticulous. The youth carefully procure crabs from the fishermen to ensure a robust and healthy stock. These crabs are then housed in the cages, where they are provided with optimal conditions for growth and development, being fed a fishmeal daily.

Hajj Ramadhan of Prati attending to mud crabs, part of community livelihood. PHOTO | POOL

Adequate feeding

“We feed the crabs on small species of fish we get from the fishermen and have stockpiled in a freezer back on the island,” explains Mohamed Hassan, a crab feeder.

“We provide them with a daily ration of 10 grams to 15 grams of feed.”

With adequate feeding, a crab typically gains around 200 grams in a span of three weeks to a month. This knowledge was obtained during a training session attended by the youth on rearing wild crabs.

Read: ‘Incognito’ fishing vessels deny Africa $11bn in annual revenues

“Even with the training we have found that having prior understanding of crabs and how they thrive in their natural environment has helped us succeed in our endeavours,” Hassan adds.

They typically purchase crabs when they are midsized, usually 300-400 grams, at Ksh400 ($3), and then sell them at a weight ranging from 800 grams to a kilo, depending on market demand.

Opportune moment

With patience and expertise, the crab fattening boys await the opportune moment to present their prized catch to potential buyers. At present, one kilo of crab is priced at Ksh2,400 ($18.32).

Crabs shed their exoskeleton to accommodate their increasing size, a process called moulting, immediately after which they are left soft and vulnerable until their new exoskeleton hardens.

“During this period, we temporarily halt their feeding. We resume feeding after about five days, and they rapidly gain weight, as they grow until the next moulting cycle, with significant growth occurring after each successful moult,” Hassan explains.

“We must exercise extra caution during the moulting of the crabs, as they become fragile and vulnerable to injury, and even death. We have lost several crabs due to the unsuitability of the previous site, which was excessively muddy. Occasionally, they succumb to diseases, with the most common being infection by the white spot syndrome virus,” Mr Abdalla says.

Recognising their crucial role in the ecosystem, the youth involved in the crab project are not only focused on crab farming but also actively engaged in the conservation of mangroves.

They acknowledge that the health of mangrove forests is crucial for the prosperity of their crab farming initiative and the sustainability of coastal livelihoods.

Read: Africa losing $37m in low fish access fee

Ecosystem's health

To conserve mangroves, the youth participate in various activities, including mangrove monitoring and replanting, where they plant mangrove seedlings in areas that have been degraded or deforested. By doing so, they help restore and maintain the mangrove ecosystem's health and functionality.

Furthermore, they conduct educational programmes and awareness campaigns within their community to highlight the importance of mangrove conservation.

“We’re slowly instilling a sense of responsibility and stewardship among local residents towards mangrove protection,” says Hajji Ramadhan, a co-founder of the Prati group.

Among the five coastal counties in Kenya where mangroves are located, the Lamu Archipelago possesses the largest portion, covering 37,350 hectares out of the total 61,271, constituting 61 percent of Kenya’s mangrove forests.

Kilifi and Kwale counties follow, with 8,536 and 8,354 hectares respectively, each accounting for 14 percent. Conversely, Mombasa has 3,771 hectares and Tana River 3,260 hectares.