Canal de Castilla Rey (Palencia), considered the beginning of the Northern Branch, Valladolid and Medina de Rioseco, lying at the end of the Southern Branch and Campos Branch respectively. The countryside crossed by the canal is of interest for its birdlife. In the Tierra de Campos there are two large Special Protection Areas ("La Nava-Campos Norte" and "La Nava-Campos Sur") which are notable for the birds such as great bustards ("Otis tarda") which live in the dryland farming areas (sometimes described as "steppes") which are typical of the region. The canal, on the other hand, provides habitats for wetland birds such as the
Edwardsiella tarda in routine tests. This led to the description of two novel species from fish viz "Edwardsiella piscicida" (Abayneh et al., 2013) and "Edwardsiella anguillarum" (Shao et al. 2015) that were previously mis-classified as E. tarda. This might have addressed the arguments between the Japanese and American investigators with regard to the difficulty of differentiating isolates from fish and humans by the time and ended up classifying all into same species i.e. "Edwardsiella tarda". "Edwardsiella tarda" is widely distributed throughout the world. It has been found from the water in Japan all the way to the United States. In Japan it