Réserve naturelle nationale du Mas Larrieu

Réserve naturelle nationale du Mas Larrieu is a compact yet remarkably varied nature reserve straddling the border between Argelès-sur-Mer and the neighbouring town of Elne, right where the Tech river reaches the end of its course and flows into the Mediterranean Sea. The area was placed under protection in 1984, a decision taken specifically to halt the tourist construction spreading along this stretch of coast and to preserve the natural character of the river mouth.

What makes this place special?

Within a modest area of roughly 160 hectares, the reserve packs together a striking mix of habitats that rarely sit side by side elsewhere: coastal dunes, wetlands, reed beds, marshland and river-mouth woodland typical of a Mediterranean delta. This patchwork of environments allows Mas Larrieu, despite its small size, to support an impressively rich fauna — researchers have recorded more than 1,200 animal species here, the large majority of them invertebrates, alongside a substantial number of vertebrates.

What can visitors see in the reserve?

Mas Larrieu is best known for its insect life, hosting numerous species of dragonflies and butterflies, including Oxygastra curtisii, a dragonfly listed on the international red list of threatened species. Because this species is highly sensitive to water quality, its presence is a good indicator of the healthy ecological condition of the local streams and wetlands.

The reserve also lies along a bird migration route, giving nature watchers a chance to spot grey herons hunting in the shallows and European bee-eaters, brightly coloured birds that arrive during the warmer months. The landscape shifts noticeably depending on direction: toward the sea, sea-shaped dunes dominate, while further inland the scenery gives way to meadows, reed beds and riverside thickets shaped by the waters of the Tech.

How to explore Mas Larrieu

A discovery trail has been laid out for visitors, lined with information panels describing the different habitats and species found along the way. The route makes it possible to take in the full diversity of the reserve in a short walk — from dry, sun-exposed dunes to the damp, shaded corners near the river mouth. A picnic area has also been set up on site, making Mas Larrieu a good destination for a calm, few-hour walk focused on nature observation, away from the crowded beaches of nearby Argelès-sur-Mer.

Frequently asked questions

Where exactly is the reserve located? It lies south of Perpignan, across the municipalities of Argelès-sur-Mer and Elne, at the point where the Tech river meets the Mediterranean Sea.

When was the reserve created, and why? It was established in 1984 to protect the mouth of the Tech from further tourist development and preserve the natural state of the coastline.

What animals can be found here? Mainly dragonflies and butterflies, including the rare Oxygastra curtisii, as well as water and wetland birds such as grey herons and European bee-eaters.

Is the reserve set up for visitors? Yes — a discovery trail with information panels and a picnic area make it easy to explore independently.

How large is the reserve? It covers about 160 hectares and, despite its modest size, contains an unusually wide variety of habitats and species.