Scott Adams told the Shropshire Star the snake was in a plastic container with air holes punched through and was wrapped in a duvet cover against the cold. He found it outside his house in Telford last week.
Adams, 28, operates Exotic Zoo, which provides displays of exotic animals for schools and children's parties. His collection includes snakes, lizards, giant snails, hissing cockroaches, African pygmy hedgehogs and, now, an anaconda.
While 8 feet is a fair amount of snake, it is on the small side for an anaconda. The South American constrictors are the largest known snakes and can grow to be more than 30 feet from head to tail.
Adams said from its weight he expected the snake to be a Burmese python, large and fast-growing snakes that are popular as pets.
"I have signs on my car advertising Exotic Zoo so I imagine whoever has left it outside my door did so because they knew I would know what to do with it," he said.