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
Ben 10: Secret of the Omnitrix signal, picks up Sixsix, one of Tetrax's rivals, and starts tracking Ben. While attempting to reach Azmuth, they are attacked by Vilgax. Ben is ultimately successful in repelling the attack, though Gluto is supposedly killed in the conflict while protecting Gwen, who blames Ben. Tetrax's ship crashes on Azmuth's homeworld. As they enter his mountain fortress, they are attacked by a group of Florauna (Wildvine's species) which capture Gwen. Ben is depressed, and blames himself. As Ben reluctantly proceeds with Tetrax and Myaxx down towards Azmuth's lair, Tetrax empathizes with Ben, revealing his origins of how working for Vilgax cost