Learn the Protocol
A clear introduction to Grenada’s ecological mangrove restoration process
Grenada’s restoration approach is based on the Ecological Mangrove Restoration (EMR) method. EMR emphasizes understanding the site, diagnosing the causes of decline, correcting hydrology, and relying on natural regeneration wherever possible. Planting comes only after ecological conditions are restored.
This page provides a straightforward overview of the five steps. Each step links to a detailed page where the full method is explained, including how to carry out assessments, what to look for, and how to avoid common mistakes.
© Dario Sandrini
Step 1. Understand the Site
The first step is to develop a clear picture of what the site was historically and how it functions today. This includes:
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Past disturbances such as filling, excavation, blocked channels, storm effects, or changes in adjacent land use.
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Current vegetation patterns, including the presence or absence of mangrove species and the degree to which they reflect natural zonation.
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Substrate and elevation characteristics, including any signs of sulphidic soils, waterlogging, erosion, or hypersalinity.
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Ecological stress indicators that may point to hydrologic imbalance.
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Cultural and archaeological considerations, particularly in wetland areas where research (including Hanna & Giovas 2019) has shown strong associations between wetlands and pre-Columbian settlement patterns.
This step establishes the baseline. Without understanding the site’s history and present condition, restoration actions are likely to be misdirected.
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Detailed page: Step 1 – Ecological Site Evaluation
Step 2. Assess Hydrology
Hydrology is the foundation of mangrove health. In this step, the focus is on diagnosing how tidal water currently moves and whether it matches the site’s natural regime.
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Key aspects include:
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Tidal exchange and flow pathways.
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Salinity patterns and whether they reflect appropriate mixing of fresh and marine water.
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Locations of obstructions (berms, fill, storm debris, collapsed culverts).
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Water levels during different tidal stages and whether they support the intended species.
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Signs of restricted drainage, stagnant water, or unnatural ponding.
A precise hydrologic assessment ensures that the restoration actions selected in later steps address the root cause rather than the visible symptoms.
Detailed page: Step 2 – Hydrology Assessment
Step 3. Restore Ecological Conditions
Once hydrologic issues are identified, the next step is to correct them. The manual emphasizes restoring the ecological processes that allow mangroves to re-establish naturally.
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Actions may include:
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Re-opening or modifying tidal channels.
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Removing storm debris that blocks flow.
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Correcting culverts or other infrastructure affecting water movement.
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Lowering or removing artificial berms or fill that prevent tidal exchange.
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Clearing vegetation that has proliferated due to altered hydrology.
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Reconnecting isolated pools or stagnated areas.
These interventions re-establish the site’s natural water regime, which in turn resets salinity, oxygen levels, and sedimentation patterns—conditions required for mangrove recovery.
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Detailed page: Step 3 – Restoring Ecological Conditions
Step 4. Facilitate Natural Regeneration
After ecological conditions are restored, many sites regenerate without planting. Natural recruitment often brings the appropriate species into the appropriate zones.
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This step involves:
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Observing whether propagules are arriving through normal tidal flows.
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Identifying early seedling establishment and noting their elevation relative to the tide.
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Minimizing disturbances from foot traffic, livestock, or equipment.
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Monitoring vegetation shifts as salinity and hydrologic patterns return to normal.
Allowing natural regeneration reduces costs, avoids misplacement of species, and reflects how mangrove ecosystems recover following natural disturbance.
Detailed page: Step 4 – Supporting Natural Regeneration
Step 5. Plant Only When Necessary
Planting is used only when natural recovery is insufficient. According to the manual, planting is appropriate when:
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Natural propagules cannot reach the site.
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Severe disturbance has removed seed sources.
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Specific zones require targeted supplementation.
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Community planting events form part of the restoration plan and align with ecological conditions.
When planting is required, best practice includes:
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Matching species to elevation and hydroperiod.
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Using healthy propagules and placing them at the correct depth.
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Avoiding planting in deep standing water.
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Maintaining natural spacing instead of uniform rows.
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Protecting seedlings from wave action, trampling, or debris.
Planting is most successful when the underlying hydrology and ecological conditions have already been restored.
Detailed page: Step 5 – Planting Guidelines
Why This Approach Works
This protocol is effective because it prioritizes ecological function over cosmetic planting. It reduces the risk of failure, aligns with natural recruitment patterns, and ensures that restoration efforts are sustainable. It also supports the stewardship of wetlands that have both ecological and cultural importance.
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Users who read this page should:
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Understand the overall logic of EMR.
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Know what each step is meant to accomplish.
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Be prepared to click into the detailed sub-pages for practical instructions.
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Recognize that planting alone cannot fix a degraded site.