- The Santa Olalla lagoon dried up at the end of August last year, and wintering waterfowl numbers in Doñana were the second lowest in the historical series.
- Rainfall was very low with only 282 litres, one of the driest years of the last 43, after a series of 4 dry years, and August recorded the highest temperatures ever in the Park.
Doñana Biological Station (EBD), from the ICTS of the Doñana Biological Reserve (ICTS-RBD), presented yesterday the results of the Monitoring Programme of Natural Processes in the Doñana Natural Area during the year 2022. This monitoring programme periodically collects scientific information to analyse the evolution of the conservation state of Doñana and to detect changes in the ecosystems, such as the appearance of invasive species or pests, the decline or recovery of populations or the progressive desiccation of wetlands. The results are presented annually to the Doñana Natural Area Office and to the regional authorities.
"Today we present the report on the monitoring carried out during the 2021-2022 hydrological year, which has been one of the worst since we began recording data in the 1970s. The intense and prolonged drought caused by climate change and the pressure exerted by human activities outside the protected area have left their mark on the different indicators of the state of biodiversity in Doñana. Our role as a research centre is to obtain the data and make it available to the policy makers responsible for management and to society as a whole. Social concern for the conservation of Doñana is great and today, fortunately, the different administrations are working together to ensure that Doñana continues to be an asset for the future," said Eloy Revilla.
The Monitoring Programme covers several areas, ranging from monitoring the physical environment and water status of Doñana, to estimating the conservation status of the main habitats and, of course, monitoring species and its populations. In the data obtained in recent years, which have been presented during the event by the vice-director of the EBD, Javier Bustamante, we can highlight that the hydrometeorological cycle from September 2021 to September 2022 was characterised as dry and warm, following the trend observed during the last decade. At the Palacio de Doñana weather station, 282,5 litres of precipitation were recorded. It was the year with the lowest annual rainfall of the last ten, the second driest since 2004-05, when the minimum of the historical series that began in 1978 was recorded, with only 169.8 litres, and the fourth driest of the series. In terms of temperatures, this was the cycle with the highest maximum temperature (46.30°C) and the highest average annual temperature (18.53°C) recorded.
The time that the Doñana marshes remained flooded, known as the hydroperiod, which depends fundamentally on rainfall, was very short, with a very negative anomaly (difference with the annual mean), due to the low rainfall. As a consequence, the wintering of water birds was very low. In the January 2022 census, when the International Waterbird Census coordinated by Wetlands International is conducted, the number of birds counted was only 80,880, a worryingly low number. In fact, it was the second worst figure in the entire historical series of January censuses (n=47), having to go back 35 years, to January 1975, to find a lower figure (44,601 birds). The January census usually coincides with the maximum number of waterbirds, but in this hydro-meteorological year, that figure was reached in November 2021, with 87,488 birds. These numbers are worrying and are a far cry from last season's peak (474,830 birds) and even further from the peaks of the late 1980s and early 1990s, with figures that exceeded 600,000 birds wintering in Doñana.
The breeding season for waterbirds in Doñana was also poor due to the drought. The red kite (Milvus milvus) has a sedentary breeding population and a migratory wintering population in the Doñana Natural Area. The latter is mostly made up of individuals from other more northerly breeding areas. Unfortunately for this species of bird of prey, catalogued in the recent Red Book of Spanish Birds as "Endangered", the number of wintering birds obtained in 2022 was the lowest in the whole series, with only 89 birds, most of them located in areas of the Natural Park. The downward trend is still very worrying.
The rabbit (Oryctolagus cuniculus) is a keystone species in Mediterranean environments, as it is a very important prey for many predators, including the Iberian lynx (Lynx pardinus) and the imperial eagle (Aquila adalberti), and is a herbivorous species that shapes the ecosystem. The species has suffered from various diseases (myxomatosis, viral haemorrhagic pneumonia) that have kept populations at very low densities. In 2022 the rabbit in Doñana recorded one of the lowest density values in the historical series with 0.20 rabbits/km.
During the event, Eloy Revilla concluded that "science has played a fundamental role in understanding, valuing and conserving wetlands. In the case of Doñana, its conservation was born from the creation of the Doñana Biological Station, a CSIC research centre dependent on the Ministry of Science and Innovation. In addition to our research work in the areas of ecology and biodiversity conservation, the EBD nowadays carries out important research coordination work in Doñana, as well as a fundamental part of the monitoring of natural processes through the ICTS Doñana Biological Reserve, in coordination with the Doñana Biological Reserve".