Weathering Severe Losses

After waiting through a few weeks of exceptionally rough wave action, our team finally had a clear window to conduct a maintenance dive at the Swahili Nurseries and inspect our outplanted reef structures. However, as soon as our Divemaster Omar, and our project leader arrived on location, it was immediately clear that the ocean’s force had taken its toll. Four of our six surface marker buoys were missing, signaling that the turbulent swells at the very end of the low season had hit our restoration site far harder than anticipated.

We began our assessment at the coral nurseries. While the structures themselves proved resilient, the extreme conditions caused coral fragments were missing. We replaced four buoyancy floaters and fixed six others that were leaking or had damaged caps; these were removed and taken out for replacement on our next dive. The relentless surge had also shifted one of our depth gradients uncomfortably close to an adjacent nursery at the line. More damagingly, along the shallowest line, we found a shattered fish trap tightly entangled in the support ropes of a nursery. Although we managed to free the gear, the thrashing trap had stripped away a significant number of growing coral fragments.

The most heartbreaking discovery awaited us on the shallow end, where we went to assess our coated metal cage structures. Out of eleven cage groups, only three remained intact. The other eight groups (accounting for 56 individual cages) were completely destroyed. While our strong anchors remained fixed to the substrate, mangled metal fragments were scattered across the seafloor as if crushed by an explosion. A clear, dredged pathway scraped across the reef toward the shallows suggested that the structures broke loose under intense wave action and dragged along the seabed. Scattered across the bottom lay large Pocillopora and Acropora colonies with broken zip ties still attached. These are now our priority to reattach to the nurseries.

Walking back from the boat across the intertidal zone, we collected another dozen discarded batteries washed onto the reef flat, illustrating the ongoing burden of marine pollution from fishermen alongside seasonal ocean forces. While our coral nurseries generally held firm, losing the vast majority of our outplanted cages is a major setback for our project. Marine restoration in an open, dynamic environment inherently carries risk, and events like this offer stark lessons on structural strength and wave energy. As we clean up the debris, our team is already evaluating the damage and plotting a feasible way forward with our coral nurseries.