Ancient Coastal Forests Submerged Off Mozambique Now Thrive as Rich Marine Biodiversity Sites

Researchers at the Bazaruto Center for Scientific Studies (BCSS) Ocean Observatory have verified that woodlands that once stretched along Mozambique’s shoreline roughly 5,000 years ago are presently thriving underwater, developing vast peat reefs that support a diverse marine community.

Utilizing underwater imaging and sediment cores around the Bazaruto Archipelago, the group charted the hidden forests. Their investigations uncovered thick strata of intact trunks and roots, now coated with marine life, showing that the former land‑based ecosystem has been converted into a vibrant subaqueous habitat.

The peat reefs arose after post‑glacial sea‑level rise flooded the coastal woodlands, trapping organic matter in oxygen‑free environments. Over thousands of years the submerged timber compacted into peat—a carbon‑dense layer that stays mostly preserved beneath the water. As peat sequesters carbon for extended spans, these reefs constitute a notable, yet frequently ignored, element of the coastal carbon balance.

From an ecological standpoint, the reefs provide three‑dimensional habitats that draw fish, crustaceans and numerous invertebrates, forming biodiversity hotspots akin to coral reefs in their ability to underpin intricate food webs. The mix of hard and soft surfaces, together with a continual leaching of organic nutrients from the peat, underpins a lively assemblage of organisms that depend on the reefs for refuge and nourishment.

This finding underscores the importance of acknowledging submerged ancient forests as significant marine ecosystems deserving protection. Scientists suggest that additional research could deepen insight into how these habitats aid carbon sequestration, boost fisheries yields, and bolster resilience to coastal erosion. Conservation officials are now evaluating ways to weave these concealed reefs into marine‑protected‑area frameworks, safeguarding their ecological roles for generations to come.