In the 1985 Law of natural spaces, the drylands of Segrià and Utxesa were already considered part of the natural spaces of Catalonia. In 1990, the whole expanse of water, some 260 ha, was declared a wildlife nature reserve and is included in the catalogue of the wetlands of Catalonia, as it is one of the most important areas. It is part of the PEIN (Plan for Areas of Natural Interest of Catalonia) and the Natura 2000 Network.
The reservoir area serves as a regulation level for the Seròs canal. This channel carries water from the river Segre and begins in the north of Lleida. It extends over 27km until the Carratalà dam in the municipal district of Aitona, and the Seròs hydroelectric power station, where the water goes back into the Segre.
This area that is used for a multitude of activities, mainly related to leisure and scientific study. Utxesa is suitable for routes by bike, on foot, running, on horseback etc. for experts, amateurs and families as it is very flat and accessible, ideal for all ages. There are some very interesting places that attract observers and photographers from all around, be they lovers of landscapes, nature in general or scientific experts. The scientific importance of some of the area's wildlife and plant habitats and species is worth highlighting. This makes it ideal for the observation, learning, and general study of different aspects of nature, especially ornithology.
One of the most significant leisure activities enjoyed in Utxesa is catch and release fishing as it is a fishing refuge. There are various competitions, but apart from this, it's also a great place to spend a relaxing day fishing with family and friends.
FLORA AND VEGETATION
Characteristic vegetation from the area includes kermes oak and black hawthorn maquis, native to the western plains of Catalonia, despite the fact that they are somewhat degraded and substituted in some areas with scrub, heathlands and brome thickets. At the foot of the valleys, and linked to the proximity of the tail waters of the reservoir, saline soils are formed that are home to a rich halophilic vegetation; one of the most comprehensive, without a doubt, of those represented in the inner parts of the natural space. Representing the halophyllic community is herbaceous glasswort, with some populations of tamarisks and limoniums, rich in rare and endemic species.
The most characteristic communities in the landscape are, however, the heathlands of ramose false-brome and esparto grass. Saved from farming activities, small sections of these interesting steppe heathlands from the plains of the Ebro have been conserved. The most nitrogenous areas are covered with Mediterranean saltwort meadows with white wormwood. These communities are entirely dominated by Mediterranean plants and some Mediterranean steppe floral peculiarities.
The reservoir, with its eutrophic waters and lots of floating matter, sustains submerged and floating hydrophilous populations, which in turn constitute the habitat of many aquatic invertebrates. Borders are covered with dense holophytic vegetation, which is well conserved and creates an ideal habitat for numerous aquatic birds. This riparian vegetation, native to wet and watery areas, is an unparalleled feature in a territory that is pseudo-steppic in nature. There are reed beds and marshes of rushes throughout the areas of water together with other more isolated and spontaneous wetland communities.
The riparian forests are more fragmented and accompanied by hygrophytic grasslands and calcic meadows. The edges of the water currents harbour very rich flora and allow the entry of the only Euro-Siberian plants that can survive in these drylands.
The unique situation of this wetland area on the western plains of Catalonia determines the presence of highly significant wildlife populations. The fish inhabiting the reservoir of Utxesa include just three native species: the barb, Parachondrostoma miegii and the European chub all of which are in clear decline; and up to 6 species introduced from elsewhere.
Regarding mammals, the otter and the Mediterranean horseshoe bat are noteworthy. Notable among amphibians and reptiles are the Spanish pond turtle, European pond turtle and Hermann's tortoise among others. But, despite being the most apparent, they are not the only relevant species; a good number of invertebrates such as butterflies, dragonflies and hawkers are also very interesting in the area.
Utxesa is one of the enclaves of the Catalan interior that is of most ornithological interest. The characteristic habitats of Utxesa wetlands are a unique refuge for more than 200 bird species, including migrants and residents.
It is important to emphasize the importance of the area for birds linked to the reed beds, in so far it has been considered one of the 23 most important localities in Catalonia for these types of birds and, specifically, the most important for the bearded reedling, the common reed bunting and the moustached warbler. Other interesting reed bed birds also nest in the area, including the Eurasian reed warbler, Great reed warbler, the streaked fantail warbler and the Cetti's warbler.
In these wetlands some Ardeidae (Heron) species such as the purple heron and the great egret, the Savi's warbler, the grey heron and the little egret, the little bittern or the black-crowned night heron. It is also a stop in the migratory and wintering stages of numerous species of ducks including the water rail, the moorhen, the coot, and the little grebe. Among birds of prey nesting in the area the most noteworthy are the black kite and especially, the marsh harrier in so far as the area houses the larger part of the population of this species in Catalonia.
The characteristics of the space, with a handful of habitats forming a great mosaic, gives rise to a variety of very important species, of which we must emphasize: the European eagle-owl, the rednecked nightjar, the European nightjar, the little owl, the barn owl, the golden eagle, the booted eagle, short-toed snake eagle, the red kite (with a roost with the fifth largest number of individuals in Europe), the falcons such as the peregrine falcon and the Eurasian hobby, the common kestrel, the European bee-eater, the European roller, the stone-curlew, the common kingfisher, the calandra lark, the greater short-toed lark, the Thekla's lark, the tawny pipit, the black-eared wheatear, the stock dove and the red-billed chough, to name a few. Together, they make the Segrià and Utxesa drylands a must see bird watching destination at different times of the year.