Full scientific report: Sierra Leone
Generated 13 November 2026, 02:10 from live Atlas data
Executive summary
Atlas holds 216,141 mapped features and 37,971 observations in 25 datasets. The mapped mangrove canopy covers 149,725 ha in 8,520 polygons across 1 formation classes; Mangrove dominates with 100.0% of the area. The median patch is only 0.177 ha, while patches of 10 ha or more hold 96.8% of the area. 0 ha (0.0%) lies within 10 km of the LAPSSET development footprint.
Single mapping epoch (2019). Areas are geodesic hectares recalculated from geometry.
Species & formations
| Formation | Polygons | Area (ha) | Share | Mean patch (ha) |
|---|---|---|---|---|
| Mangrove | 8,520 | 149,725.0 | 100.0% | 17.57 |
Fragmentation & landscape metrics
- Patches
- 8,520
- Mean / median / largest
- 17.57 / 0.177 / 8,906.3 ha
- Effective mesh size
- 2,890.8 ha
- Largest patch index
- 5.9%
- Power-law exponent α
- 1.50
Spatial clustering
Global Moran’s I = 0.245 (z = 7.4, p < 0.001). Hot-spot cells (Gi*, ≥95%): 41; cold-spot cells: 28.
| Top hot-spot cell | Polygons | Area (ha) | Gi* z |
|---|---|---|---|
| 7.55, -12.55 | 26 | 5 | 3.11 |
| 8.6, -13.1 | 44 | 1,136 | 3.07 |
| 7.55, -12.35 | 12 | 2,438 | 3.03 |
| 8.6, -13.15 | 34 | 1,524 | 3.00 |
| 8.55, -13.05 | 46 | 93 | 2.90 |
| 8.95, -13.25 | 255 | 1,435 | 2.83 |
Pressure: LAPSSET and villages
Mangrove ha by distance from LAPSSET
Mangrove ha by distance from villages
Data quality
| Dataset | Features | Repaired | Score |
|---|---|---|---|
| Global Mangrove Watch: mangrove extent 2020, Sierra Leone | 15,970 | 0 | 100 |
| Global Mangrove Watch: mangrove extent 1996, Sierra Leone | 12,221 | 0 | 100 |
| Global Mangrove Watch: mangrove extent 2007, Sierra Leone | 12,064 | 0 | 100 |
| Global Mangrove Watch: mangrove extent 2010, Sierra Leone | 11,686 | 0 | 100 |
| Global Mangrove Watch: mangrove extent 2015, Sierra Leone | 10,644 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 2025, Sierra Leone | 13,043 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 2020, Sierra Leone | 8,520 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 2015, Sierra Leone | 7,791 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 2010, Sierra Leone | 6,632 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 2005, Sierra Leone | 6,819 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 2000, Sierra Leone | 7,255 | 0 | 100 |
| Global Mangrove Watch v4.1: mangrove extent 1996, Sierra Leone | 8,092 | 0 | 100 |
| Fibre Cable Landing Stations | 126 | 0 | 95 |
| Rivers | 228 | 0 | 95 |
| Power Plants (Power output MW) | 642 | 0 | 95 |
| Small airport | 1,979 | 0 | 95 |
| Dams | 2,586 | 0 | 95 |
| Districts | 6,099 | 13 | 95 |
| World Database on Protected Areas | 7,438 | 1 | 95 |
| Electricity Transmission Network | 9,759 | 0 | 95 |
| Divisions | 17,649 | 9 | 95 |
| Irrigated Areas | 23,095 | 1 | 95 |
| Agro-Ecological Zones | 25,791 | 17 | 95 |
| Carbon projects: Sierra Leone | 2 | 0 | 90 |
| Community and nature projects (UNDP): Sierra Leone | 10 | 0 | 90 |
Recommendations
Datasets & sources
| Dataset | Publisher | Features |
|---|---|---|
| Global Mangrove Watch: mangrove extent 2020, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 15,970 |
| Global Mangrove Watch: mangrove extent 1996, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 12,221 |
| Global Mangrove Watch: mangrove extent 2007, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 12,064 |
| Global Mangrove Watch: mangrove extent 2010, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 11,686 |
| Global Mangrove Watch: mangrove extent 2015, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 10,644 |
| Global Mangrove Watch v4.1: mangrove extent 2025, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 13,043 |
| Global Mangrove Watch v4.1: mangrove extent 2020, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 8,520 |
| Global Mangrove Watch v4.1: mangrove extent 2015, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 7,791 |
| Global Mangrove Watch v4.1: mangrove extent 2010, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 6,632 |
| Global Mangrove Watch v4.1: mangrove extent 2005, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 6,819 |
| Global Mangrove Watch v4.1: mangrove extent 2000, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 7,255 |
| Global Mangrove Watch v4.1: mangrove extent 1996, Sierra Leone | Global Mangrove Watch (Aberystwyth University, soloEO, Wetlands International, UNEP-WCMC, JAXA) | 8,092 |
| Fibre Cable Landing Stations | WWF Kenya | 126 |
| Rivers | WWF Kenya | 228 |
| Power Plants (Power output MW) | WWF Kenya | 642 |
| Small airport | WWF Kenya | 1,979 |
| Dams | WWF Kenya | 2,586 |
| Districts | WWF Kenya | 6,099 |
| World Database on Protected Areas | WWF Kenya | 7,438 |
| Electricity Transmission Network | WWF Kenya | 9,759 |
| Divisions | WWF Kenya | 17,649 |
| Irrigated Areas | WWF Kenya | 23,095 |
| Agro-Ecological Zones | WWF Kenya | 25,791 |
| Carbon projects: Sierra Leone | Berkeley Carbon Trading Project, University of California, Berkeley | 2 |
| Community and nature projects (UNDP): Sierra Leone | United Nations Development Programme (UNDP) | 10 |