(PR / 22-02-11) In the coming months, Oceana will be presenting new data, video footage and photographs taken off the coast of Doñana National Park. This documentation was compiled during the 2010 Oceana Ranger Expedition, conducted with the support of Fundación Biodiversidad (Spanish).
Oceana’s scientists are currently studying this material, including species never before found in the area. The expedition produced the most number of hours of HD video filmed with an underwater robot (ROV) in the area and the analysis of the data will enable us to identify areas of greatest ecological interest and support proposals for their protection.
Over the last four years Oceana has researched the sea beds of the Doñana area with the use of professional divers and an underwater robot. This has made it possible to determine which areas are most important with regards to biodiversity, such as, for example, the coastal front of Rota and Chipiona, where dense forests of tree coral (Dendrophyllia ramea) have been located and other areas further north, opposite Mazagón, where there is an abundance of rocky slabs which are populated with various species of gorgonians and sessile bryozoans.
The Guadalquivir Marine Reserve covers almost all of the internal waters included in Oceana’s proposal. However, the area between Rota and Chipiona is not protected. These 80 ha included in the Oceana proposal are of the greatest ecological importance, because offshore there is predominantly a compacted muddy seabed and the ecosystems are simpler.
The studies developed in recent years have led to the discovery of the high rates of biodiversity in the Gulf of Cadiz; however, there is still an important lack of information, which becomes more severe as we move away from the coast.
The published documents concerning the infralittoral and circalittoral areas are mainly focused on commercial species or describe the areas’ physical and geological characteristics. However, the few studies which have been published reveal the wide variety of flora in these areas, including various species of seagrass, such as Zostera spp. or Cymodocea nodosa, rhodophycean or phaeophycean algae, most described as being between Mazagón and the mouth of the Guadalquivir River.
Concerning fauna, we find commercial species such as the wedge shell (Donax trunculus) or the venus clam (Chamelea gallina), although there are high levels of diversity among molluscs and other marine fauna, as well.
Also spotted were several species of crustaceans, such as the fiddler crab (Uca tangeri), cephalopods including the octopus (Octopus vulgaris), species of fish such as the sand smelt (Atherina boyeri) or the seahorse (Hippocampus hippocampus), as well as various annelid species.
Apart from these species, cetaceans are also present in this area, including the bottlenose dolphin (Tursiops truncatus) or the harbour porpoise (Phocoena phocoena) and turtle species like the loggerhead turtle (Caretta caretta) or the green turtle (Chelonia mydas).
Samples taken by Oceana over the past three years have shown the presence of a wide variety of molluscs and fish, as well as ascidians, holothurians, star fish, urchins, anemones, banks of mysids, copepods and different larvae.
Various species of corals have also been identified atop dispersed slabs of sandstone, including Dendrophyllia ramea and Caryophyllia spp., gorgonians including Leptogorgia sarmentosa and Elisella paraplexauroides, as well as hydrozoans, bryozoans, sponges, tunicates, etc.