Whiteley found the snake, a non-venomous boa constrictor, stuck between two fence posts.
"The boa constrictor was a large snake at around 5-foot long and he was quite wide. He'd tried to slither through the fence and got wedged," Whiteley said. "Luckily, I was able to carefully wiggle him free and he wasn't injured at all."
Whiteley said the snake is being cared for by a specialist while officials search for the presumed escaped pet's owner.
"I've put up posters in the local area and have added the boa to PetsLocated," Martin said. "If anyone thinks this might be their snake then I'd urge them to get in touch by calling the RSPCA's inspectorate appeal line."