British Wildlife Wiki

The Corn snake (Pantherophis guttatus guttatus), or red rat snake, is a North American species of rat snake that subdues its small prey by constriction. The name "corn snake" is a holdover from the days when southern farmers stored harvested ears of corn in a wood frame or log building called a crib. Rats and mice came to the corn crib to feed on the corn, and corn snakes came to feed on the rodents. The Oxford English Dictionary cites this usage as far back as 1676.

Corn snakes are found throughout the southeastern and central United States. Their docile nature, reluctance to bite, moderate adult size 3.9–6.0 feet (1.2–1.8 m), attractive pattern, and comparatively simple care make them popular pet snakes. In the wild, they usually live around 6–8 years, but in captivity can live to be up to 23 years old.

In the UK

The Corn snake is constantly being released or escaping from pet owners in the UK as they are a very common pet. Usually people who are just starting to collect snakes would buy this as a 1st pet then get bored of it and just let it go into the wild. Numbers are uncertain in the wild. But they can with stand our winters so who knows how many are now breeding due to the vast amount or releases or escapes.