Doñana National Park

Wild boar population has increased greatly within the National Park in recent years. Wild boars pose one of the key threats to the bird species within the National Park (EBD, 2016).

Some tourism infrastructure developments near Mazagón were documented in 2008, and the general disturbance from a high level of weekend tourism has been highlighted (WWF, 2008). However, the abstraction of water to supply the town and beach resort of Matalascañas, especially in the summer when more than 90,000 tourists arrive, is significant. It takes place from a set of five wells up to 150 m deep, taking water from the aeolian sands sub-unit of the Almonte-Marismas aquifer. As a result, some nearby lagoons located in the Doñana Biological Reserve, such as Brezo or Charco del Toro, have permanently dried-out since 1976 and 2010, respectively (Hollis et al.,1989; Díaz-Paniagua & Aragonés, 2015). The flooded surface and inundation occurrence of other ponds such as Zahillo have also decreased as a direct consequence of groundwater withdrawal in the coastal resort (Dimitriou et al., 2017, Fernández-Ayuso et al., 2018). By contrast, Santa Olalla permanent pond seems unaffected at the time (Fernandez-Ayuso et al., 2019), as it is located further from the pumping wells than the above-mentioned ponds and at a preferential groundwater discharge area. According to the latest annual report of the Status of Doñana aquifers (Guadalquivir River Basin Authority, 2020) the coastal and ponds areas are considered to be in a pre-alert status. To address environmental concerns, plans have been put forward to close wells nearer the impacted lagoons and to transfer water from other sectors of the province for public supply.

Illegal egg collection and bird and large herbivore poaching have been documented from the World Heritage site, as well as illegal fishing and persecution (poisoning) of wild animals (WWF, 2008). There reportedly is also illegal fishing of European eel (Anguilla anguilla) which returns to breed in the lower Guadalquivir. The status of the population is so bad that glass eel fishing has been banned since 2011, although illegal fishing remains a problem. However, due to the relatively effective management of the site, in comparison to other threats this threat is significant, but low.

A number of fenced roads both within and around the World Heritage site are contributing to habitat fragmentation. Despite the fences, there is also a high amount of roadkill including the Iberian Lynx. For example, 2,298 vertebrates were killed on roads inside the site in nine months in 2007 (WWF, 2008). A "Special Plan" implementing the Regulations of the Doñana Region Land Plan is meant to "establish a balance between the development of agricultural activity in the vicinity of Doñana and the environmental impact of this activity", noting the decision that the "functional structure of the agricultural area needs to be compatible with the road system and rural routes providing access to the holdings, and the services and equipment linked to agricultural activity and their users" (State Party of Spain, 2016). It was added that "Measures need to be taken to permeate the agricultural area to allow for the movement of wildlife through the creation of an ecological connectivity, and precautionary measures need to be taken to ensure compatibility with the road system and all the rural routes". Once this is put into place so that fragmentation and roadkill is reduced, this threat will also be reduced, but at this point in time it remains high.

The 1998 Aznacóllar mine accident led to the poisoning of the Guadiamar River with heavy metals and other toxic materials, which affected the property (UNEP-WCMC, 2011). In 2013, the regional government issued a public bid for reopening the mine, and in 2015 one international bid was received for its exploitation. In 2016, the State Party reported in its state of conservation report that the project has not proceeded to implementation but a research project has been authorized. In 2019, the State Party shared the project’s EIA and indicated that the IUCN World Heritage Advice Note on Environmental Assessment was expected to be incorporated. In response, the World Heritage Committee urged Spain to prepare a clear risk preparedness plan and rapid emergency response capacities and to submit these analyses for review by IUCN, as soon as they become available and before a decision on re-opening the mine is made (State Party of Spain, 2019; UNESCO, 2019). 

In addition, several municipalities on tributaries of the wetlands of the World Heritage site such as Almonte, Rociana de Condado and Matalascañas, reportedly have insufficient waste water treatment systems in place. The Spanish government was fined by the European Union in 2016 for the lack of adequate water treatment in Matalascañas (La Nueva España, 2016).

Contamination from industrial water pollution, including on the Guadalquivir River (CSIC et al., 2011) constitutes a threat, as does pollution from agriculture (fertilizers and pesticides). However, imported water for irrigation comes from the Andevalo-Chanza dams, whose basin is sparsely populated and not intensively cultivated, so its quality is good.

In 2019, the State Party reported the hydrological condition inside the World Heritage site as stable (State Party of Spain, 2019), however the annexed 2016-2017 Guadalquivir Hydrographic Confederation report on the status of the aquifers indicated a stabilization of the aquifer sections inside the site at “pre-alert” and “alert” levels, whilst four sections partly adjoining the northern boundary of the property are reported to be in an “alarming” state (UNESCO, 2019). Furthermore, infringement proceedings issued by the European Commission regarding the Habitats and Water Framework Directives are currently underway (UNESCO, 2019).

The combined pollution from various sources of water entering the site constitutes a high threat, contributing to the entrance of nutrients and eutrophication.

In 2008 and 2009, a large number of fires inside and in the vicinity of the property affected 84,000 ha of the site and its surroundings. Fires affect forest areas in particular and appear to be largely caused by humans, with more than 40% started intentionally (WWF, 2010). In 2017, a large fire which occurred outside of the site threatened the site and caused problems with the Iberian Lynx captive breeding facility (El País, 2017). The fire affected about 40 species of flora, including the endemic Linaria tursica¸38 species of mammals and 75 species of birds. In addition, 13 habitats of community interest and 3 of primary community interest have been affected (SEO/BirdLife, 2017a). No fires have been reported to impact the property since, and the current threat appears to be low, however climate change will also influence the number and intensity of wildfires in future (Green et al., 2017).

Both alien plant (e.g. Eucalyptus, Acacia spp., giant cane Arundo donax, burdock Xantium strumarium, Nicotiana glauca and alien floating fern Azolla filiculoides) and alien animal species (e.g. American Crayfish Procamburus clarkii in the wetlands, Chinese Mitten Crab Eriocheir sinensis in the Guadalquivir estuary) have been detected inside the property (UNEP-WCMC, 2011; State Party of Spain, 2016; Green et al., 2017). 96% of the fish biomass inside the marshland of the National Park are invasive alien species (Moreno et al., 2013). These alien invasive species are currently classed as low threat although they may in effect be a higher threat to the OUV of the site, particularly with climate change and eutrophication of the water. Three species of fish have disappeared from the site, caused in part by invasive species (WWF, 2017).

The floodplain marshes of Doñana Park are a flood-pulse system in which their water levels and extent of inundation are determined primarily by high surface flows arriving rapidly after winter rainfall from the Guadiamar River. Groundwater only makes a significant contribution to flows is late summer. Other small tributaries, such as the La Rocina River also provide some freshwater to the marshes and are partially surface and partially groundwater-fed. The southern extreme of the marshes, where the Guadiamar River joins the Guadalquivir estuary, can be inundated by brackish water at high tide, particularly since re-opening of the levee in 2013/15, which previously separated Doñana from the Guadiamar. There is thus a gradient of fresh to brackish marshes from north to south.

The average rain in the area is 540 mm (1970/71-2018/19). The area has suffered two prolonged periods of heavy drought 1979-80 to 1982-83 (305 mm average rain) and 1991-92 to 1994-95 (350 mm) and is experiencing a long mid-dry period since 2011/12, with only 460 mm of average rain. This circumstance must be taken into account when interpreting current piezometry. The Doñana area is underlain by the Almonte-Marismas detritic aquifer composed of deltaic sands. This aquifer outcrops in the north but inclines to the south, being covered by up to 100 m of clay beneath the Doñana marshes. Water from the aquifer has been abstracted for agriculture, such as strawberries (now covering 6000 ha in the eastern area), fruits, cotton, rice, and orchards. The CHG has recorded water levels in a very dense network of 292 piezometers with some data going back before 1974. In many piezometers, groundwater levels are consistent with rainfall. However the CHG declared that three of the five groundwater bodies that share the aquifer to the north of Doñana National Park are at risk of failing to achieve Good Status as required under the European Union Water Framework Directive (WFD) because of low and declining groundwater levels, even taking into account the low rainfall since 2011. Some aquifer water levels are lower than during the drought of the mid-1990s, though others are higher. This has given rise to fears that the water supply to Doñana is at risk due to abstraction. However, the available evidence is that the detritus aquifer does not contribute significantly to flooding of the marshes and satellite images suggest that the area of marsh has not fluctuated more than would be expected by changes in rainfall. Nevertheless, uncertainty in knowledge of the interaction between aquifers and with rivers, marshes and lagoons means that a risk remains. The State Party report (2016) recognised the need to set limits on the extraction of groundwater resources for irrigation and the associated irrigated area that would protect the ecosystems in the Doñana Natural Area. To implement this, abstraction from the detritic aquifer is being reduced as part of a CHG plan that combines five measures: (1) stopping illegal abstraction (2) reducing the area of groundwater-irrigated land (3) adjusting legal abstraction during dry periods (4) providing surface water from dams (e.g. Agrio in the Guadiamar) and other catchments (such as the Guadiana River) for irrigation to replace groundwater and (5) enhancing control with water agents, telecontrol of water meters and remote sensing of land use. Some 5 hm3 per year have already been provided to offset groundwater abstraction, but 15 hm3 per year are still required, which will necessitate new infrastructure. Closing the first wells involved a 7-year practical, administrative and legal process. However, implementing the CHG’s plan, which includes closure of 544 wells, should return the degraded aquifers to Good Status by 2027. Achievement of Good Status is in the interests of abstractors as it ensures protection of future water resources in the aquifer. Since Good Status equates to near-natural groundwater levels, achieving it should adequately protect any groundwater-dependent ecosystems. Thus, recovery of the detritic aquifers to Good Status should remove any potential hydrological risk to Doñana of abstraction from its underlying aquifers (IUCN Consultation, 2020). 

The vegetation cover of the marshland of the marsh area of the National Park shows evident signs of strong overgrazing.
There is a positive correlation between the breeding success of waterfowl colonies and their location in areas with perimeter fencing of livestock exclusion in certain areas of the marsh, areas where these structures have kept the marsh vegetation in good condition, indicating the negative effects of overgrazing on the conservation of these birds. Overgrazing compromises the state of conservation of aquatic birds in Doñana in the Plan of Recovery and Conservation of Birds of Wetlands of Andalusia (SEO/BirdLIfe, 2015).

No impact studies have been carried out since the admission of the 'rocieros'. The pilgrimage of El Rocío attracts more than 40,000 people, who cross areas of high ecological value during the breeding season of birds, which undoubtedly generates important and significant impacts on biodiversity that have never been quantified (SEO/BirdLife, 2017a). Domestic waste, including plastic bags and bottles, left by pilgrims is a significant, though temporary, issue.

The European Environment Agency has stated that countries of the Mediterranean have experienced decreased precipitation and increased temperature over past decades. This trend is projected to worsen with reductions in river flows (Estrela et al., 2012) and recharge to aquifers (Molano-Leno et al., 2018; Naranjo-Fernández et al., 2020) possibly diminishing groundwater inputs to the property (Guardiola-Albert & Jackson, 2011). The size of permanent and semi-permanent lagoons is strongly correlated with annual rainfall (Díaz-Paniagua & Aragonés, 2015). Recent research suggests that a decline in species, such as zooplankton (Florencio et al., 2020), has been related to long-term reduction of wet period length of temporary freshwater ponds within the Park. Species of shrews, mice and rats have been declining with increasing temperatures and lighter rainfall (Santoro et al. 2017). Diving birds and vegetation gleaners are likely to decline in future climate scenarios, while many small wading birds will benefit from changing conditions. Resident species and those that breed in this wetland may be more negatively impacted than those using this area for wintering or stopover (Ramírez et al, 2018). Climate change will also influence the number and intensity of wildfires as well as affect a wide range of additional potential threats including an increase in alien floating plants and cyanobacterial blooms (Green et al., 2017) which need to be studied in more detail. A study (Scheffer et al., 2015) alerts a number of actions carried out in Doñana, leaving it vulnerable to climate change.

The national programme to monitor closely global change in the Spanish National Parks does not yet include Doñana (IUCN Consultation, 2020), but its incorporation could provide indicators for its particular types of wetland ecosystems that are not covered by other coastal National Parks participating in the programme. Also, it might be helpful to include Doñana as a particularly helpful case to illustrate concrete adaptation and mitigation measures for the regional climate change strategy of the government of Andalucía.