There is no single river in Bulgaria that is not damaged, either alone or with its tributaries, from pollution, from drying up, from barriers to the migration of species in it, from digging for aggregates or from sewerage. That's why the World Wildlife Fund (WWF) is signalling the problem. 

At the same time, contrary to our perceptions, our country is relatively poor in water resources - they represent only 0.3% of our territory. For comparison with an average water resource for the world of 8000 cubic meters per person per year, Bulgaria has only 2250 cubic meters per person per year.

At present 325 rivers in our country have 270 hydroelectric power plants built and another 200 have been granted a building permit. We are accustomed to perceiving HPPs as "green energy". In practice, however, they are barriers that change the watercourses, the speed and the flow of the rivers, thus blocking the possibility of migration of dozens of species of fish and invertebrates. The fish passes, which are built according to the law, usually miss very few fish and do not allow them to follow their usual route, WWF said.

Adding to other factors such as climate change and the destruction of riparian forests, it is no wonder that 60% of the Danube fish populations and its tributaries have disappeared over the last 20 years, says the eco-organization.

The Red Data Book of Bulgaria already has 50 species of fish, of which 4 have been completely extinct and 46 are threatened. Among them are the sturgeons, an ancient species, 200 million years old, the same age of the dinosaurs.

The fish are part of whole ecosystems, that is why the disappearance of a species is not a harmless event. It would cause irreversible changes throughout the environment, WWF said.

The positive thing about the situation is that there is something to be done. The World Wildlife Fund calls for protection of the European law governing human intervention in water bodies - the Water Framework Directive adopted in 2000. It is currently under review and this is the best chance protect the life in the Bulgarian rivers for the next 20 years, the organization adds. The deadline for submitting proposals under the directive is March 4.