|NASA Photo ID||ISS051-E-12705|
|Time taken||13:55:58 GMT|
latitude/longitude of image
features and other details
information about camera used
|Nikon D4 Electronic Still Camera|
|4928E: 4928 x 3280 pixel CMOS sensor, 36.0mm x 23.9mm, total pixels: 16.6 million, Nikon FX format|
|4928 pixels||3280 pixels||No||No||NASA's Earth Observatory web site||Download|
|720 pixels||480 pixels||Yes||No||NASA's Earth Observatory web site||Download|
|4928 pixels||3280 pixels||No||No||Download|
|640 pixels||426 pixels||No||No||Download|
An astronaut took this photograph of a section of Isla Mayor, an island in the delta of the Guadalquivir River in southwestern Spain. The DoÃ±ana National Park is a marshland nature reserve that has been proclaimed a UNESCO World Heritage site. The larger, multi-colored geometric shapes in the scene are fish ponds, while the smaller, dark rectangles are rice fields.
The fish farming practiced here tries to mimic natural conditionsÂ—maintaining the original wetland conditionsÂ—more closely than many Â“intensiveÂ” fish farms around the world. These larger ponds are fed with river water, which contains natural food types, especially algae and shrimp, without commercial fish feed or antibiotics. Such larger fish ponds reduce problems, such as fish diseases and degradation of the pond water, and raise marketability. Species farmed here include sea bass, grey mullet, meagre, and shrimp.
Cattle raising and rice farming are being progressively phased out of the area as part of a wider plan to surround the DoÃ±ana park with environments that resemble the original wetlands. The region is becoming one of the largest bird refuges in Europe, attracting almost 250 species of migratory birds each year. Fish taken from the ponds by birdsÂ—amounting to about 20 percent of the fish populationÂ—are viewed as part of an ecosystem in balance.