Mangroves in Black River District

Overview

The Black River district, located on the leeward (west/southwest) coast of Mauritius, is characterized by relatively smaller, fragmented, and linear mangrove patches compared to the windward east coast. These forests are primarily estuarine, thriving where rivers descend from the Black River Gorges to the sea. The district is a center for restoration ecology, with significant reforestation at Le Morne and Case Noyale helping to reverse historical clearing for boat passages and coastal development.

Statistics - Black River

Maconde - ~26285 m²
Le Monde ~57291.3 m²
Case Noyale ~47860 m²
Petite Rivière Noire ~40368 m²
Les Salines - Ilot Fortier ~13321 m²
Grande Rivière Noire ~41477.3 m²
Tamarin ~45638.4 m²
Albion ~508.4 m²

District of Black River_Total ~272749.4 m² (or ~27.27 ha)

Dominance: Rhizophora mucronata

Black River District

District Area: 259 km²
Population ('000, 2021): ~85.2
Climate
Mangrove Area: ~27.27 ha
Map

Albion (BR-A)

Coverage: Small, isolated patches near the mouth of the Belle Eau river and around the rocky inlets.
Abundance: Low density; primarily pioneer Rhizophora mucronata.
Relevant Info: Being at the northern edge of the district, these mangroves face high pressure from urban runoff and recreational beach use. They serve as a critical localized "green lung" for the rocky Albion coastline.

Tamarin River Estuary (BR-T)

Coverage: Fringing strips along the brackish riverbanks and the inner bay.
Abundance: Moderate; characterized by dense root systems that provide high structural complexity.
Relevant Info: This is a vital nursery for the Mud Crab (Scylla serrata). It is a prime location for eco-kayaking, though it is highly sensitive to changes in freshwater inflow from the Tamarin River.

Les Salines-Ilot Fortier (BR-LS-IF)

Coverage: Fragmented patches surrounding the islet and the edges of the historic salt pans.
Abundance: Moderate; recovering patches integrated with marshy wetlands.
Relevant Info: This site is ecologically unique as it interacts with hypersaline environments. It is a critical habitat for migratory birds and is a key site for monitoring "coastal squeeze" due to adjacent luxury real estate developments.

Petite Rivière Noire (BR-PRN)

Coverage: Narrow, linear belts along the coastline and small tidal inlets.
Abundance: High density of Rhizophora mucronata seedlings in specific monitored plots.
Relevant Info: This area often shows high resilience to sea-level rise due to the gradual slope of the coastline, allowing for potential landward migration of the forest.

Grande Rivière Noire (Estuary Plots) (BR-GRN)

Coverage: Robust stands at the mouth of the island’s largest river system.
Abundance: High; adult trees show significant biomass and a canopy increase coefficient of approximately 1.82.
Relevant Info: These "Estuary Plots" (often labeled S1, S2, S3 in research) are primary sites for Blue Carbon studies. The deep silt deposits here store more carbon than the sandier sites in the north.

Case Noyale (BR-CN)

Coverage: A successfully restored corridor along the coastal road.
Abundance: Very High; over 10,000 seedlings have been propagated here.
Relevant Info: Once cleared for boat access, this site is now a prime example of community-led restoration. It acts as a bio-shield for the village against tidal surges.

Le Morne (BR-M)

Coverage: Extensive expansion; grew from 0.06 Ha to over 4.7 Ha in the last decade.
Abundance: Extremely High; over 50,000 seedlings planted in the ADD Mangrove Eco-Forest.
Relevant Info: Part of the UNESCO World Heritage buffer zone. It has the highest growth rate in the district and serves as the ultimate model for mangrove reforestation in the Republic of Mauritius.

Bel Ombre / St Martin (BR-BO-StM)

Coverage: Fringing forests that link the terrestrial biosphere to the lagoon.
Abundance: Moderate to High; stable mature stands.
Relevant Info: Located within the Black River Gorges – Bel Ombre Biosphere Reserve. These mangroves are critical for filtering agricultural runoff from the southern hills before it reaches the coral reefs.

Riviere du Cap Estuary (BR-RdC)

Coverage: Dense patches located at the sharp southern bend of the island near the Maconde viewpoint.
Abundance: High; characterized by tall, mature Rhizophora trees.
Relevant Info: This is one of the most photographed mangrove sites due to its proximity to the Maconde bridge. It provides essential shoreline stabilization for the coastal road.