Boyd Lyon Sea Turtle Fund

Background

Seagrass meadows are crucial ecosystems that sustain biodiversity, fisheries, and local livelihoods (Jahnke et al., 2019). They provide essential feeding habitats for critically endangered Hawksbill turtle (Eretmochelys imbricata), whose grazing activities in turn enhance seagrass productivity, nutrient cycling, and overall ecosystem resilience (Tol et al., 2021). Despite their ecological importance, seagrass meadows in the southwestern Indian Ocean have experienced significant degradation in recent years due to ongoing anthropogenic activities and climatic factors (Brodie & Ramon, 2018). In Zanzibar, for example, seagrass cover declined by approximately 10.98% between 2006 and 2019 (Purvis & Jiddawi, 2023), while other regional sites experienced nearly a 20% reduction over the past 13 years (Kendrick et al., 2019; Purvis & Jiddawi, 2023). These losses have significantly affected endangered megafauna that rely on seagrass habitats, particularly hawksbill turtles (Eretmochelys imbricata). Hawksbill turtles are similarly rare, exhibiting low nesting frequency, and studies suggest populations continue to decline despite shell trade restrictions and other protections due to bycatch, and loss of nesting and foraging habitats (URT, 2024). The decline of this key grazer further limits seagrass recovery, creating a negative feedback loop that threatens ecosystem stability, reduces biodiversity, and jeopardizes the livelihoods of coastal communities dependent on seagrass meadows for fisheries, food security, and other ecosystem services. While various restoration efforts have been initiated, many overlook the ecological linkages between seagrass habitats and the species they support (WIOMSA, 2020). Restoration activities often fail to consider the specific habitat requirements and feeding preferences of turtles, resulting in limited long-term success. Additionally, community involvement in the planning, monitoring, and protection of these critical habitats remains low, further weakening restoration outcomes and conservation sustainability. To address these challenges, this project will focus on identifying and mapping critical foraging habitats, characterizing seagrass species preferred by Hawksbill turtles, and promoting community-led protection measures aimed at reducing bycatch risk in key feeding zones.  The findings of this study will provide vital ecological insights to guide habitat-specific restoration and strengthen the integration of turtle conservation into coastal resource management. Ultimately, the project seeks to enhance the recovery of Hawksbill turtles by restoring and safeguarding their foraging habitats, thereby reestablishing the ecological linkages that support both seagrass productivity and turtle population resilience along the southern coast of Tanzania.

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General Objective

To enhance the recovery and conservation of Hawksbill turtles (Eretmochelys imbricata) through seagrass habitat restoration, ecological assessment, and community-led conservation initiatives along the southern coast of Tanzania.

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Specific Objective 

1. To identify and map critical Hawksbill turtle foraging habitats associated with seagrass meadows 

2. To characterize seagrass species composition and identify preferred species utilized by Hawksbill turtles for foraging.

3. To engage and empower coastal communities in participatory monitoring and bycatch reduction initiatives to promote sustainable Hawksbill turtle conservation.​

 

Methodology 

The project will be implemented in three key coastal districts in southern Tanzania: Rufiji, Mafia and Kilwa. These sites were selected based on their ecological significance, presence of extensive seagrass meadows, and known occurrences of sea turtle populations (West, 2011; WIOMSA, 2020). 

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1. To identify and map critical Hawksbill turtle foraging habitats associated with seagrass meadows. 

This objective will involve field surveys and participatory mapping using local ecological knowledge (LEK) from fishers, beach monitors, and coastal communities. Observational surveys of Hawksbill turtle presence will be conducted during high and low tides using small boats. GPS coordinates of turtle sightings, grazing marks, and seagrass meadow extent will be recorded. The data will be analyzed using Geographic Information Systems (GIS) to produce spatial maps highlighting critical feeding habitats and areas of high turtle occurrence. These maps will form a baseline for targeted restoration and protection interventions.

Ethical Consideration: All observations will be non-invasive, ensuring no capture or handling of turtles to avoid stress or harm.

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2. To characterize seagrass species composition and identify preferred species utilized by Hawksbill turtles for foraging.

At each identified foraging site, seagrass samples will be collected along transects (20–30 m) using quadrats (0.25 m²) at systematic intervals. Seagrass species will be identified morphologically using standard identification keys and field guides. The abundance, percent cover, and health condition (leaf length, epiphyte load, shoot density) will be recorded. Direct observations and grazing trail analysis will be used to infer turtle foraging preferences. The results will help determine which seagrass species and conditions are most suitable for Hawksbill foraging, providing evidence for restoration site selection and seeding practices.

 

3. To engage and empower coastal communities in participatory monitoring and bycatch reduction initiatives to promote sustainable Hawksbill turtle conservation.

This objective will involve community awareness campaigns, focus group discussions, and capacity-building workshops targeting at least 300 local fishers and coastal residents. Educational materials (brochures, posters, and talks) will highlight turtle-safe fishing practices and the ecological importance of seagrass habitats. Participants will be trained in simple turtle and seagrass monitoring techniques, including reporting sightings and identifying bycatch events. The project will collaborate with local fisheries officers and conservation NGOs to promote the adoption of turtle-friendly fishing gear and local bylaws for protecting key foraging zones. Community feedback will guide adaptive management to ensure long-term conservation sustainability.

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Expected Outcomes

1. Enhanced understanding of Hawksbill turtle foraging ecology

2. Evidence-based seagrass restoration and management strategies

3. Improved community participation and conservation awareness

4. Strengthened integration of habitat and species conservation

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Dissemination of Results

Project results will be disseminated through community, institutional, and scientific platforms to ensure wide accessibility and long-term conservation impact. 

At the community level, findings will be shared through participatory meetings and awareness workshops in Rufiji, Mafia, and Kilwa. Simplified materials such as posters, leaflets, and summary briefs in Swahili will be distributed to enhance local understanding and encourage sustained engagement in habitat protection.

At the institutional and policy level, reports and policy briefs summarizing key findings and recommendations will be shared with the Ministry of Blue Economy and Fisheries, local governments, and the Tanzania Fisheries Research Institute (TAFIRI). Collaborative dissemination workshops will be held with partners such as WIOMSA and conservation NGOs to strengthen management integration.

For the scientific community, a technical report and at least one peer-reviewed paper will be produced, with presentations planned for national and regional conferences such as TAWIRI and WIOMSA symposia.