Fisheries & oceans
Strategies for Restoring Biodiversity in Coastal Lagoons to Enhance Fisheries Resilience and Ecosystem Service Provision.
Coastal lagoons harbor diverse species and support valuable fisheries; restoring biodiversity requires integrated governance, habitat rehabilitation, community engagement, and adaptive management to strengthen resilience, sustain catches, and maintain critical ecosystem services over time.
August 07, 2025 - 3 min Read
Coastal lagoons are dynamic, productive interfaces where freshwater and seawater mix, creating unique habitat mosaics that support a range of fish, invertebrates, birds, and microbial communities. Yet they face growing pressures from pollution, overfishing, dredging, and climate variability. Recovery hinges on understanding ecological relationships that connect nursery habitats, feeding grounds, and tidal exchange. Effective restoration blends habitat creation with water quality improvements and floodplain reactivation. Actions include reestablishing seagrass beds, rebuilding mangrove or saltmarsh margins, and restoring natural hydrological regimes. When designed with care, these measures yield cascading benefits for non-target species, soil stabilization, and nutrient cycling.
Achieving resilient fisheries through biodiversity restoration begins with mapping the lagoon's biological baseline. Scientists and local stewards collaborate to identify keystone species, critical breeding sites, and seasonal migrations. This knowledge informs prioritization—where restoration will yield the greatest ecological and economic returns. Baselines also guide monitoring frameworks that track changes in species abundance, genetic diversity, and trophic interactions. In practice, robust monitoring requires simple, community-friendly indicators alongside advanced analytics. Shared data streams help managers detect early warning signals of degradation, allowing timely interventions. Transparent reporting reinforces trust among fishers, policymakers, and conservation organizations.
Integrating water quality, habitat, and governance for durable outcomes.
Habitat restoration in lagoons often centers on physical improvements that recreate structure and refuge. Constructed oyster reefs, rock gardens, or submerged vegetation patches provide shelter for juvenile fish and invertebrates while offering substrate for biofilm formation, a fundamental food source. Restored channels and controlled flows reestablish connectivity between nursery grounds and open water, enhancing larval survival. Importantly, restoration should avoid unintended consequences, like preferentially favoring one species at the expense of others. Side benefits include reduced shoreline erosion and improved sediment stability. Equally vital is designing with climate threats in mind, ensuring features endure warming, acidification, and extreme storms.
Beyond physical form, biodiversity restoration must address water quality and nutrient balance. Lagoon systems accumulate nutrients from adjacent waters, which can trigger algal blooms and hypoxic zones if not managed. Implementing green infrastructure around the catchment, promoting microbial denitrification, and reducing input of phosphorus are essential steps. Biomanipulation, where appropriate, can restructure food webs to increase predator control and suppress harmful algal blooms. However, such interventions require careful timing and long-term observation. Coupled with community stewardship, these measures help maintain clearer waters, clearer horizons for fishers, and healthier detrital cycles that support juvenile lifecycles.
Co-management and local knowledge as pillars of durable lagoon restoration.
A cornerstone of biodiversity-driven resilience is the protection and restoration of critical nursery habitats. Seagrass meadows, saltmarshes, and shallow mangrove fringes serve as refuge from predation, feeding grounds, and nurseries for a broad spectrum of species. Restoring these habitats involves sediment stabilization, eelgrass restoration, and careful reestablishment of hydrological connections. It also requires pressure management so that nurseries are not repeatedly disturbed by dredging or fishing gear. Stakeholders must balance short-term harvests with long-term habitat viability. When nurseries thrive, recruitment improves, leading to steadier catches and more predictable incomes for coastal communities.
Community-led restoration is a powerful catalyst for sustainable fisheries. Local fishers bring practical knowledge about seasonality, spawning times, and preferred habitats, which complements academic research. Participatory planning ensures that restoration aligns with livelihoods, reducing resistance and enhancing compliance. Co-management arrangements—where communities, government agencies, and researchers share decision authority—tackle conflicts, distribute benefits equitably, and foster adaptive learning. Education campaigns highlight the ecosystem services lagoons provide, from flood protection to carbon sequestration. As trust grows, communities invest time and resources into restoration projects, creating a virtuous cycle of stewardship and improved resilience to climate shocks.
Genetic resilience and adaptive capacity through connected habitats.
Biodiversity restoration must be complemented by species-specific recovery strategies. Some focal species may recover quickly with habitat enhancements, while others require targeted protection, genetic management, or assisted dispersal to overcome barriers. Protecting spawning aggregations, reducing bycatch through selective gear, and enforcing seasonal closures help safeguard vulnerable populations during critical life stages. Recovery plans should be species informed, yet ecosystem-based, recognizing that the fate of one species often cascades to others in the network. Flexibility matters, as climate-driven shifts may alter habitat suitability. Regular review of recovery targets keeps programs aligned with the best available science and evolving local needs.
Genetic diversity underpins adaptive capacity, enabling populations to withstand disease, temperature fluctuations, and shifting prey resources. Conservation strategies must prevent genetic bottlenecks by maintaining interconnected habitats that allow natural dispersal. When barriers appear, managers consider managed translocations only after rigorous risk assessments and stakeholder consultation. Maintaining a mosaic of microhabitats supports diverse life history strategies, boosting resilience across seasons and years. It is essential to couple genetic goals with habitat restoration so that recovered populations have the space to adapt and flourish. In parallel, citizen science can help track genetic indicators and distribution patterns at a finer scale.
Sustainable finance and shared accountability for long-term outcomes.
A holistic restoration approach integrates multiple ecosystem services, recognizing that biodiversity supports more than protein from fish. Enhanced nursery habitats stabilize shorelines, filtering pollutants and buffering against storm surges. Seagrasses and marshes trap sediments, contributing to carbon sequestration and clearer waters that improve visibility for hatchlings. Restored lagoons also support tourism, recreational fishing, and educational programs, expanding the economic and cultural value of coastal systems. Embedding traditional ecological knowledge alongside Western science creates more robust narratives for restoration success. When communities see tangible benefits beyond harvests, they sustain engagement and long-term investment in protection measures.
Financing restoration requires innovative models that blend public investment, private stewardship, and international aid where appropriate. Payments for ecosystem services can reward fishermen and landowners who maintain habitat features and water quality. In-kind contributions—such as equipment, labor, or monitoring services—often offset initial costs and foster local capacity. Transparent budgeting, performance-linked funding, and independent audits build confidence among funders. Long-term financial planning should anticipate maintenance needs, including invasive species control, sediment management, and climate adaptation infrastructure. Sustainable finance aligns ecological goals with community prosperity, ensuring that restoration remains viable across generations.
Monitoring and adaptive management are the engines of enduring restoration. Establishing clear indicators—such as juvenile recruitment rates, species diversity, and dissolved oxygen levels—allows managers to detect trajectories of change. Adaptive management embraces experimentation: attempting complementary approaches in different lagoon sectors while learning from outcomes. Regular feedback loops ensure policies adjust to new data, stakeholder experiences, and ecological thresholds. Integrated monitoring should harmonize scientific rigor with cost-effectiveness, employing remote sensing, local surveys, and traditional knowledge. Communicating results openly fosters trust and motivates continued participation. Ultimately, adaptive governance translates ecological insight into resilient fisheries systems.
The path to resilient coastal lagoons lies in sustained collaboration, persistent habitat care, and prudent use of resources. Restoration is not a one-off fix but a long-term commitment to ecosystem health and human well-being. By pairing habitat rehabilitation with water quality improvements, protective gear changes, and inclusive governance, lagoons can rebound with richer biodiversity and more reliable harvests. The cumulative benefits extend beyond fisheries to climate resilience and cultural vitality. As communities observe healthier ecosystems, investments deepen, new partnerships form, and the legacy of stewardship becomes embedded in daily practice. This is how biodiversity restoration translates into enduring coastal resilience.
