Diawling

Diawling National Park is located in the Trarza region of southwestern Mauritania, adjacent to the Senegal River delta and directly bordering the Djoudj National Bird Sanctuary in Senegal. The park covers approximately 15,750 square kilometres and protects a complex mosaic of wetland, floodplain, and Sahelian savanna ecosystems in one of the most ecologically significant areas of West Africa. The park was created largely in response to the ecological transformation caused by the Diama Dam, constructed on the Senegal River in 1986, which altered the hydrology of the delta region by blocking the seasonal tidal influx of salt water. Diawling is managed with an explicit goal of restoring and maintaining the wetland ecosystems of the Mauritanian Senegal delta while supporting the livelihoods of local communities who depend on the wetland resources. It is a Ramsar Wetland of International Importance.

Diawling National Park is one of the most important wetland wildlife areas in West Africa, particularly for waterbirds and migratory species. The park serves as a critical wintering and staging area for millions of migratory birds following the East Atlantic Flyway, including pelicans, herons, egrets, and numerous shorebird species. The African spoonbill, purple heron, black-crowned night heron, and African darter are among the breeding species. Wattled crane, an increasingly rare species in West Africa, has been recorded in the park. West African manatee inhabits the deeper river channels and is subject to conservation monitoring. Nile crocodile is present in the permanent water bodies. Hippopotamus persists in small numbers. The floodplain grasslands attract large numbers of wading birds and waterfowl during the flooding season. A diverse fish fauna supports both wildlife and the local artisanal fishing economy.

The vegetation of Diawling is dominated by wetland and riparian plant communities that have been significantly altered by the construction of the Diama Dam and subsequent water management interventions. Prior to dam construction, the delta was characterised by brackish and estuarine vegetation adapted to seasonal salt water intrusion. With freshwater now dominant, extensive reed beds of Typha domingensis and Phragmites australis have expanded greatly, in some areas displacing more diverse wetland communities. Water lilies, floating-leaved aquatics, and submerged vegetation occur in the permanent water bodies. The terrestrial margins of the park support Sahelian acacia woodland and degraded savanna transitioning to the broader Sahel landscape. Mangrove vegetation, once more extensive in the delta, persists in small remnant stands.

Diawling occupies the delta and lower floodplain of the Senegal River, a geologically young landscape shaped by the interplay of river sediment deposition, Atlantic Ocean tidal processes, and aeolian inputs from the adjacent Sahara. The surface is characterized by flat alluvial plains, river channels, interdune depressions, and low dunes built from Saharan sands reworked by coastal wind processes. The underlying geology consists of Quaternary sediments deposited by the river and ocean over thousands of years. The delta is a dynamic and geomorphologically active system, with channels shifting position over time and the coastline changing in response to sediment budgets and sea level variations. The construction of the Diama Dam upstream has fundamentally altered the sediment regime of the lower delta, with consequences for long-term coastal stability.

Diawling experiences a semi-arid Sahelian climate with a single short rainy season from July to September, during which the annual precipitation of 250 to 400 millimetres falls. The rest of the year is dry, with the harmattan wind from the Sahara dominant during the cool dry season from November to February. Temperatures are hot throughout the year, with peaks above 40 degrees Celsius in May and June before the rains. The coastal influence moderates temperatures somewhat in the west of the park. The flooding regime of the park, which is managed through a system of dykes and sluices constructed after the Diama Dam was built, is critical to the ecological functioning of the wetlands. Rainfall variability across the Sahel is high, and drought years significantly reduce the extent and duration of flooding.

The Senegal River delta has been inhabited for millennia by Peul (Fulani), Wolof, Moor, and other communities who have developed sophisticated livelihood systems based on fishing, pastoralism, and flood-recession agriculture. The periodic flooding of the delta created a productive mosaic of resources that sustained relatively dense human populations in an otherwise harsh environment. Colonial administration brought the region under French control, and the post-independence development agenda included large-scale hydraulic infrastructure projects on the Senegal River, including the Diama Dam at the river mouth and the Manantali Dam upstream in Mali. These dams, built to provide irrigation water and flood control, transformed the hydrology of the delta and had profound negative consequences for traditional livelihoods and wetland ecosystems before a more nuanced management approach was adopted.

Diawling National Park was established in 1991, explicitly as a conservation response to the ecological disruption caused by the Diama Dam completed five years earlier. The dam's elimination of seasonal salt water intrusion had dramatically altered the wetland ecosystems of the Mauritanian delta, causing the mass die-off of salt-tolerant vegetation and the displacement of many traditional fishing and pastoral communities. The park was created in partnership with the IUCN and with funding from the Netherlands government, with the innovative goal of managing water flows through a system of dykes and sluices to simulate pre-dam ecological conditions. This approach, integrating ecological restoration with community participation, was internationally recognised as a model for wetland conservation in areas affected by hydraulic infrastructure.

Diawling's primary attraction is wildlife watching, particularly the spectacular concentrations of waterbirds that use the managed wetlands during the flooding season. The park offers boat excursions through the water channels and flooded areas, allowing close observation of pelicans, herons, and wading birds. Fish eagle, osprey, and numerous kingfisher species can be observed along the waterways. The border with Senegal and the adjacent Djoudj National Bird Sanctuary means that the broader delta area offers exceptional wildlife watching across both countries. Visits to fishing communities within the park provide insights into traditional wetland-based livelihoods. The park is most rewarding to visit during and immediately after the flooding season, from October to January, when bird numbers are at their peak.

Visitor infrastructure at Diawling is modest. The park is accessible from the Mauritanian town of Rosso on the Senegal River border, which is connected by road to the capital Nouakchott. The park entrance is reached via tracks from the main road. A small ecolodge and camping facilities provide basic accommodation within the park, and there is a visitor information centre. Boat excursions on the water channels must be arranged through the park administration. The best time to visit is the post-flooding period from October to February. Guides are available and should be engaged for boat trips and for navigation in the more remote parts of the park. The crossing to Senegal at Rosso allows combined visits to the adjacent Djoudj National Bird Sanctuary, which has better visitor infrastructure.

Diawling's conservation model centres on the active management of water levels through the dyke and sluice system to maintain ecologically appropriate flooding regimes that support both biodiversity and community livelihoods. This requires constant maintenance of the hydraulic infrastructure and the negotiation of water allocation decisions that balance ecological needs with those of farming and fishing communities. Invasive plant species, particularly Typha reeds which have expanded dramatically since the dam was built, remain a significant management challenge, blocking water flow and reducing habitat diversity. Unsustainable fishing practices, including the use of fine-mesh nets that capture juvenile fish, threaten the long-term productivity of the fishery. The park works closely with local communities through participatory management committees that give community representatives a voice in resource use decisions, an approach that has improved local ownership of conservation outcomes.