Biologists call for a network of protected rivers

Science Daily: An international research team has used the Guadiana River basin [in Spain and Portugal], in which 92% of the species are under threat, as a reference point to measure the loss of aquatic biodiversity and its conservation value. A new study reveals that the state of fragmentation of Iberian river basins is "seriously endangering" the freshwater fish that inhabit them, and highlights the need to create new protected aquatic reserves.

"At present, conservation of waterways is both insufficient and inefficient, as water courses within nature reserves are nearly always used simply as administrative boundaries that do not guarantee the conservation of aquatic biodiversity", Virgilio Hemoso, chief author of the new study and a researcher at the University of Queensland, Australia, tells SINC.

The study, which has been published in the latest issue of Hydrobiologia, is based on the premise that there are few nature reserves for the conservation of aquatic biodiversity. "Rivers have been treated as being of secondary importance, unless they represent an opportunity to conserve the land environment", Hermoso adds.

…In order to design a reserve system that protects aquatic biodiversity, the biologists evaluated the fish communities in the Guadiana River basin. With so few resources being devoted to conservation, and conservation itself competing with other human uses, the researcher stresses that "it is more sensible to focus conservation efforts on water courses with healthy populations".

In order to do this, the team measured potential biodiversity loss and calculated the conservation value. Their method highlights areas that have not suffered significant losses of biodiversity and which "are therefore worthy of special attention."
Guadiana River basin, a reference point in conservation

In the context of the Mediterranean, the Guadiana River basin stands out due to both its richness in freshwater fish species, "which is only comparable to that found in two other river basins: the River Po in northern Italy and the River Orontes in southern Turkey", and the degree to which it is threatened. "This makes it an ideal place to hone tools and processes which could be applied to other Mediterranean river basins", Hermoso states.

An aerial view of the Guadiana River in Portugal, shot by Besnier.m, Wikimedia Commons, under Creative Commons Attribution 2.5 License