Bird Observatory of the Las Cañas Reservoir Nature Reserve

About

Name of organisation

Ostadar Environmental Education Society

Funding support

Government of Navarra (Spain)

Number of staff

3

Number of visitors per year

Overall aims of the centre

To inform and raise awareness among the general public about the values of the site and its problems. To inform and raise awareness among the local population.

Description of the centre

Bird observatory
Various panels provide visitors with a wide range of information on the Network of Protected Areas of Navarre; the situation of Las Cañas Reservoir; water uses; vegetation present (tamarisk, reed and rushes); wintering birds (common pochard, lapwing, grey heron, shoveler, cormorant, mallard, coot, etc) and nesting birds (red-crested pochard, moorhen, grebe, little bittern, night heron, little egret, little egret, grey heron).

From this centre, equipped with binoculars and telescopes, visitors can also enjoy the life of the different species in this Nature Reserve. The visit to this observatory can be complemented with an itinerary around the reservoir, which allows a closer observation of the species. The Salobre or Las Cañas reservoir is located on communal land in the municipality of Viana, just a few hundred metres from an industrial estate in the city of Logroño.

The lagoon covers an area of some 101 hectares and has a maximum depth of 4 or 5 metres. The reservoir collects runoff water from a catchment area of 6 602 hectares through a network of streams and irrigation channels and can hold a volume of water of around 2 cubic hectometres.

History
It is known that the present reservoir is located on an ancient lagoon of endorheic origin which was enlarged by the construction of two dykes: one dividing the wetland area in two and limiting the old reservoir and the other outside the old reservoir and forming the new reservoir.

Protection
The first measure to protect the Las Cañas reservoir was taken in 1987 with the enactment of Provincial Law 6/87 on Regional Town Planning Regulations for the Protection and Use of the Territory. By means of this Law, the reservoir was included in the network of protected natural areas of Navarre as a Nature Reserve. The same year, 1987, saw the graphic delimitation of this wetland area by Foral Decree 289/1987.

In 1990, the wetland was incorporated into the network of Special Protection Areas for Birds in accordance with the definition of Directive 79/409/EC on birds. Also in 1990 the Spanish Ornithological Society included it in the list of Important Bird Areas in Spain.

The protection established was specified in 1991 by means of the Use and Management Plan (Foral Decree 138/1991) and the Regulations for the planning of leisure and recreational activities in the Salobre or Las Cañas Reserve (Foral Decree 139/91).

Geology
The basin of this enclave is located on Miocene materials (Tertiary period) made up of clays, silts and sandstones of palaeochannels. The area is endorheic in origin and collects runoff water from a wide basin. Uses of the lagoon Hunting was for years an obstacle to the use of the lagoon by aquatic fauna. Today it is prohibited. Fishing for tench and carp is authorised from the containment dike. The pond is also used on a restricted basis for irrigation.

Botany
The marsh vegetation consists of reeds and bulrushes. In contact with this type of vegetation, there are meadows with rushes formed by species of the genera Puccinellia, Scirpus and Juncus. At one end, the one closest to the road, there is a tamarisk woodland which, although not very extensive, provides the shrub support for the installation of the night heron nests. This colony is the most important in the region and one of the most important on the Iberian Peninsula.

Zoology. The bird community
The most outstanding feature of the Cañas de Viana reservoir is the high diversity of species it hosts. In this respect, it surpasses the ornithic biodiversity of the Pitillas lagoon, although there is no serious study that can corroborate this in a scientifically rigorous manner. Perhaps the most characteristic group of species of the wetland are the birds of prey and their greatest exponent is the Night Heron, which maintains an important nesting colony with fluctuations in numbers.

It is undoubtedly the most important in Navarre. The presence of other birds such as the Bittern, the Little Bittern, the Purple Heron and the Little Egret is also important. It is the only lake in Navarre where the Red-crested Pochard has been nesting regularly. Another notable fact in the pond is the presence, especially in winter and spring, of numerous accidental species with an almost unique presence in this enclave.

Among these are the Common Pelican, the Little Egret, the Great Egret, the Little Dipper, the Black-billed and Red-billed Pochard, etc. It is the enclave with the highest concentration of accidental species in Navarre. In recent years, the presence during the winter of a large group of cormorants has been very noticeable. They have a large roost on the banks of the river Ebro, just a few kilometres away as the crow flies.

Criteria for the inclusion of the Las Cañas reservoir (Viana) in the Ramsar list of wetlands.

Presence of a colony of kingfishers well above the criterion of international importance, with a maximum of 470 nesting pairs in 1994.
Presence of an important Purple Heron colony also above the required criterion.
Regular presence of Bittern.
Regular presence of the spotted crake.