5. Populations and species
This program focus on:
18.104.22.168 Threathened flora: since 2005 the ICTS-RBD team, the national park and Dunas del Odiel Botanical garden have been monitored the distribution and population dynamics of threatened plant species present in the protected areas of Doñana. During these years 118 taxa have been included, most of them endemic species associated with oligotrophic coastal and wetland habitats. The information is incorporated into the threatened flora and of interest in Andalusia (FAME) database and its visualizer. See protocol and a summary of data. Request draw data.
5.1.2. Invasive Flora:
22.214.171.124 Oxalis pes-caprae: the presence of Oxalis pes-caprae, commonly called sourgrass, was recorded in Doñana in the oaks of the “Pajarera” in December 2013. Eradication tasks were iniciated to control the population in the occupied sites. Since 2014, annual surveys are carried out to detect and evaluate the extent of the occupied area. After the location, the species is usually eliminated from the invaded points, clearing and removing the biomass and the bulbs. The plant remains obtained are eliminated by controlled burning. See summary of data. Request raw data.
1.1. Waterbirds: Doñana is a site of great importance for waterbirds, and they were probably the main factor behind its initial conservaton status in the mid-60s and its selection as one of the two first Spanish wetlands to join the Ramsar List in 1982. Indeed, Doñana meets Ramsar’s 6th criterion (‘supporting 1% of its population’) for at least 18 species; it hosts more than one third of the Spain’s wintering population of greylag goose, Eurasian teal and northern shoveler; and it is the main wintering site in Spain for at least 15 species. Doñana also hosts large breeding populations of more than 10 species, including conservation icons such as the marbled teal and red-knobbed coot. Waterbirds were the first group to be regularly monitored in Doñana and still represent one of its main monitoring efforts.
1.1.1. Aerial censuses: aerial censusses were the first standardized monitoring program introduced in Doñaña, with the early support of Tour de Valat. Initiated in the early 1970s, it has been carried out at monthly intervals since then. Aerial censuses are made from a small plane and cover all large wetlands (lakes, marsland, river branches and rice fields) over an area of 84.628 ha, which includes the Eastern margin of the Guadalquivir marshes and part of the Western margins included in the Doñana National and Natural Park. Besides rare and occasional observation, 49 species of waterbirds are regularlyregistered in the census. See protocol and summary data. Request raw data.
1.1.2. Ground censuses: aerial censuses are complemented since the 1980s by ground-based surveys of waterbirds and other non-passerine birds across the Guadalquivir marshes and other wetlands included in the Doñana Protected Areas. These surveys provide estimates of habitat use (particularly, in small wetlands such as sandy lakes), allow for the monitoring of bird species that cannot be surveyed reliably from the air (e.g. grebes, herons, purple swamphen, gulls and terns) and for the detection of rare or threatened species or rallids and ducks (such as the red-knobbed coot, marbled teal, ferruginous duck and white-headed duck). Surveys are coordinated at national level and take place five times a year, in january, april, june, september and november. In january, the survey forms part of the International Waterbird Census. In these surveys, all white-headed ducks are carefully observed in order to detect individuals of or potential hybrids with ruddy duck, whose presence is communicated to the Park’s authorities since they are subjected to a control program. For threatened and/or protected species, all reproductive pairs detected in the surveys are subsequently monitored fortnightly to evaluate their reproductive success. See protocol and summary data. Request raw data.
1.1.3. Colonial breeders: the main aggregations of colonial breeders are monitored regularly during the whole breeding period. This monitoting program focuses in the heronry present in the Doñana Biological reserve (pajarera de Fuente del Duque), which is monitored monthly, from february to august, using telescope observations from a predetermined set of vantage points. The surveys provide information on the number of breedind pairs, as well as their productivity (number of eggs, chicks and fledged chicks per nest). See protocol and summary data. Request raw data.
1.1.4. Non-colonial breeders: non-colonial breeders aremonitored by means of horseback transect across the Doñana marsh. Transects follow a pre-defined itinerary, and the observers register the presence of nests of the different species, the number of eggs or chicks per nest, and the occurence of nest predation. Surveys take place at monthly intervals during the complete breeding season, at 5 different transects of 9.5 to 16.8 km. This protocol focused initally oncommon coot and purple swamphen, but it provides regular observations of several species. See protocol and summary data. Request raw data.
1.2. Beach and litoral birds: Doñana Protected Areas include one of the largest natural beaches in the Iberian Peninsula. Its beach represent an strategic point to survey the coastal movements of seabrids from the Atlantic and Mediterranean seas. It is also a key point in the Eastern Atlantic flyway for many Charadriiformes (waders, gulls and auks), and provides a vantage point from which to record the abundances of other migrants using the Doñana marshes as resting and feeding areas. Since 1990, the ICTS-RBD ‘beach censuses’ provide standardized estimates of the population trens of all these groups of birds. Surveys consist of observations made from a 4×4 vehicule along two predefined transects of 29 km (national park) and 23.5 km (natural park), and take place at monthly intervals. See protocol and summary data. Request raw data.
1.3. Raptors: Doñana is also well-known for the diversity and abundance of its raptors.
1.3.1. Colonial raptors: Doñana host roosting sites of three raptors, the red kite, western marsh harrier and Egyptian vulture. These sites are surveyed once a year, coinciding the International Waterbird Census, using telescope observations from vantage points. See protocol and summary data. Request raw data.
1.3.2. Breeding raptors: breeding raptors are intensively surveyed by the ICTS-RBD monitoring program – particularly for endangered (red kite, hen harrier) or localy rare species (peregrine falcon, black-winged kite, short-toed snake eagle, western marsh harrier, northern goshawk and Eurasian hobby). Reproductive pairs are identified and active nests monitored to asses their reproductive success (number of eggs, chicks and/or number of fledged chicks per nest). Surveys take place from march to september. See protocol and summary data. Request raw data.
1.4. Perching birds (passerines):
1.4.1. Breeding passerines: surveys of starting passerines were initiated in 2005, but the methodology was adjusted in 2012 to the national program SACRE. In both cases, surveys took place twice a year (april-may and may-june). (i) From 2005 to 2012, distance-sampling surveys were based in visual observations over 100-m transects. They included 10 different transects situated in 5 habitat types (gallery forest, shrubland, marsh-sand grass ecotone, pine forest and marshland). (ii) Since 2012, surveys are based on distance-sampling at point stations, in which the observer recordes all birds singing over a period of 5 minutes. They were reduced to 4 localities (at 4 habitat types) and based on 20 points per locality. See protocol and summary data. Request raw data.
1.4.2. Wintering passerines: These surveys are integrated in the national program of bird censuses SACIN. They take place rwice a year (november-december and january-february) and consist of transects of 4,0-5,6 km in which the observer walks for 120 minutes and registers all birds observed. See SACIN protocol and summary data. Request raw data.