From Ridge to Reef: A Holistic Ecosystem Based ICZM Approach

Rivers are vital - sustaining life, shaping ecosystems, and contributing to the wellbeing of local communities. In Mauritius, rivers are under increasing pressure but remains poorly understood impeding efforts to preserve them. Focused on the Jacotet river at Bel Ombre, this project aims to highlight the importance of a ridge-to-reef approach to restore rivers, protect ecosystems, and support coastal health. It promotes collaboration between local communities, terrestrial and coastal managers for better environmental resource management.

Funded through the RECOS (Resilience of Indian Ocean coastal zones) project by the Indian Ocean Commission (IOC), Agence Française de Développement (AFD) and Fonds français pour l’environnement Mondial (FFEM). This pilot project spans 21 months (2024-2026), and involves collaboration between scientists from the Reef Conservation, experts from GroundTruth and Nature Metrics. Together, they aim to enhance the understanding and preservation of river ecosystems in Mauritius.

Project Objectives

The project is guided by five specific objectives:

1. Investigate the relevance that stakeholders place on the ecosystem services provided by watersheds and rivers and the importance of freshwater biodiversity to local communities.
2. Assess river health and inventory biodiversity from ridge to reef to improve knowledge of status, linkages to associated ecosystems and responses to restoration / mitigation actions
3. Empower private sector and community through citizen science approaches to participate in ecosystem monitoring and build capacity for stewardship and management of rivers, watersheds and coastal zones.
4. Investigate best practices and nature-based solutions for river corridor restoration and management adapted to different natural and human created stresses.
5. Evaluate how inclusive stakeholder and ecosystem-based watershed management can support sustainable coastal zone management.

Importance of rivers to stakeholders of the region

we organized a series of focus group discussions and conducted an extensive survey across the Bel Ombre region. These engagements were designed to capture insights on how rivers contribute to livelihoods, food security, and other needs, while also uncovering gaps about freshwater biodiversity. The data collected will serve as a cornerstone for developing inclusive management strategies that reflect local priorities, strengthen stewardship, and guide efforts to mitigate pressures on river ecosystems. This participatory approach ensures that conservation actions are not only scientifically sound but socially relevant, fostering long-term sustainability for both watersheds and coastal zones.

Assessing Freshwater biodiversity of the Jacotet Watershed

River ecosystems are vital for maintaining ecological balance, acting as corridors that connect upland watersheds to coastal zones. They provide essential services such as nursery habitats for juvenile fish, nutrient cycling, and water purification, all of which underpin biodiversity and coastal resilience.

To achieve this, we conducted comprehensive sampling that included:

• Diatoms as indicators of water quality and primary productivity.
• Freshwater macroinvertebrates evaluate ecological integrity and detect stressors.
• Environmental DNA (eDNA) for a non-invasive inventory of species across the watershed.
• Electrofishing surveys assess fish species and community structure.

This multi-layered methodology enables us to establish baseline conditions, identify biodiversity patterns, and evaluate how restoration or mitigation actions influence river health and its connections to adjacent ecosystems.

Empowering Stakeholders through Citizen Science

Experiencing nature firsthand is a powerful catalyst for environmental stewardship. When individuals and organizations actively engage with ecosystems, they develop a sense of responsibility that translates into meaningful action. Yet, freshwater conservation faces a critical challenge: limited awareness of what river ecosystems are, their ecological and economic importance, and the threats they face. This knowledge gap often hinders participation in conservation and sustainable management.

To overcome this barrier, Reef Conservation implements citizen science tools such as miniSASS, a simple, science-based tool that assesses river health through macroinvertebrate sampling. By training community members, schools, and private sector partners to collect and interpret data, these sessions transform participants into active contributors to ecosystem monitoring.