The Santa Olalla lagoon, the largest permanent lagoon in Doñana National Park, in Spain, and the last one to hold water in August, has finally dried up, reports the Doñana Biological Station - CSIC.
The lagoon had been reduced to a small puddle in the centre, where waterfowl no longer flock. This is the third time this has happened since the Doñana Biological Station - CSIC began to record data on the National Park in the 1970s.
Doñana has historically been a refuge for fauna. It has an important system of lagoons, of which only a few remain with water throughout the summer, offering refuge to the first waders that migrate south after breeding in northern Europe, and they also provide habitats for a good number of strictly aquatic species of flora and fauna.
An intense period of drought
The drought affecting Europe, especially in the Iberian Peninsula, is wreaking havoc on the natural area. However, the most worrying thing is that this has been going on for a long time. "It has not rained normally for years now. Doñana has had below-average rainfall levels for ten consecutive years," says Eloy Revilla, director of the Doñana-CSIC Biological Station. Wetlands and the species that depend on them, such as waterfowl, are particularly affected and are forced to move in search of areas that keep water available during the heaviest periods of low water.
The continuous exploitation of the aquifer by intensive agriculture and extractions for human consumption, also in years as dry as this one, means that not only the temporary lagoons have disappeared from Doñana, but also the permanent ones are under threat.
"This is the third time that the Santa Olalla lagoon has dried up completely since we have records. It also happened in 1983 and 1995, in both cases also coinciding with periods of intense drought," explains Revilla. "We know from previous occurrences that it is not only drought that has caused the permanent lagoons of Doñana to disappear. Overexploitation of the Doñana aquifer is also to blame. An aquifer is overexploited when more water is extracted from it than it recharges when it rains, something that has been happening in Doñana for many years.
