The Park forms an exceptional and unique ecosystem, called wetlands, formed by the overflows of the rivers in their middle sections, that cause great pools. it great ecological worth is the bird life that uses this area in winter and for nesting, thereby creating a whole area of water birds.
Tablas de Daimiel formed as the result of overflows at the confluence of the rivers Guadiana and Cigüela, a fact favoured by the slight slope of the land. The Wetlands are strategically located on the migratory routes of many species of birds, that use the area to rest, and even spend the winter. The water birds are the absolute protagonists of the Park. They include the great crested grebe, the common grebe, black-necked grebe, herons, egrets, and all kinds of Iberian ducks. In the Wetlands numerous aquatic flowers grow.. Some grow underwater (like the horwart or musk grass), float (such pondweed) and emerging (cladium mariscum, reed and rush).