|
|
The Danube River Delta is one of the largest river deltas in Eastern Eurasia. Large populations of birds and migratory fish inhabit the ecoregion. If you like birds and fish, you’ll want to visit the Danube River. Here rare pelicans swoop over the water searching for fish, pygmy cormorants and collared pratincoles breed, and countless other birds pause during their migrations to feed in the surrounding wetlands. Also look for migrating fish such as sturgeon, eels, and Tyulka sprat. And don’t miss the freshwater mollusks, dragonflies, and amphibians -- the Danube has something for everyone.
The Danube River has a rather modest source: two springs in Germany's Black Forest. During its 1,780 mile (2,800 km) course, the river runs through cities, valleys, and deep, wide gorges. Just before the Danube pours into the Black Sea, it splits into three branches, the Chilia, Sulina, and Sfântu Gheorghe. Sandwiched between two vast plains in Bulgaria and Romania, the Danube River Delta contains 4,300 square miles (11,000 sq. km) of wetlands where birds nest, breed, or feed and rest during migrations. The maze of canals, ponds, lakes, and marshes in the ecoregion is alive with nearly 300 species of birds that live in or migrate through the delta. Historically, 73 native freshwater fish and an additional nine brackish-water species were found in the lower Danube basin. The basin is also home to approximately 90 freshwater mollusks (with 18 endemic), 75 dragonfly species, and 20 amphibian species. Historically, 10 diadromous fish species occurred in the lower Danube River. These included five sturgeon species, the European eel, three shad, and the Tyulka sprat. Today, two of the species of sturgeon are exinct in this ecoregion. Fish species endemic to the lower Danube basin are a loach and the critically endangered Asprete perch. The rare Dalmatian pelican, white pelican, water rail, pygmy cormorant, and collared pratincole also breed here.
The loss of two of this ecoregion’s migratory fish species and the risk to several more can be attributed to the modification of this ecoregion’s aquatic systems by humans. Pollution, damming, and drainage of wetlands disrupt the fragile ecology of the delta. Industry, agriculture, livestock grazing, and urban settlements have all increased the amount of sewage, agricultural and industrial wastes, and pesticides that enter the Danube’s water. Over-exploitation of some birds and frogs may be a problem, as is the introduction of exotic species. Recent human conflicts in the Danube basin have also had negative impacts on this ecoregion.
|
