Ladder Snake

The ladder snake is a medium-sized snake which reaches a maximum total length (tail included) of around 160 cm (63 in) but which averages 120 cm (47 in) in total length. It has a pointed snout. As an adult the ladder snake is less variable than many related snake species. Dorsally, it is yellowish to dark brown, with two darker stripes running down the length of the body from neck to tail. It normally also has a dark stripe running from the rear of the eye to the angle of the jaw and sometime subtle, darker markings on the sides. The ventral side is pale, varying from a silvery-grey to whitish, with the occasional dark spot. The eye is dark. The juvenile snakes have lighter and brighter colouration, varying from yellow to light brown, with the characteristic "ladder" pattern in black along the upperside. The pale underside has black markings which sometimes coalesce to cover the whole of the underside. As the snake ages these colours and patterns fade until the simpler adult pattern is left.

The geographic range of the ladder snake includes Portugal, Spain, southern France and just into Italy, also Menorca and the Iles d'Hyères off Provence, but it is absent from northern Iberia including much of the Pyrenees, Galicia (although the species is found on Ons Island, in the Atlantic Islands of Galicia National Park), Cantabria and the Basque Country. The population on Menorca may stem from an introduction by humans.

Like other "rat snakes", the majority of the ladder snake's prey is mammals such as mice, rabbits and shrews, making up 75% of prey items with a further quarter being spiders, insects (especially grasshoppers) and a few birds. To prey on birds the ladder snake will climb to search for active nests in trees or on man-made structures. Lizards are also eaten. Juvenile ladder snakes prefer small lizards, baby rodents, spiders, and grasshoppers.