David Spiegel -- a veterinarian who, with his wife, Linda, and their children, adopted Snakie 18 years ago -- told police he lets the snake sun outside in his backyard and checks on him every few minutes. But Snakie made a run for it Aug. 11 and managed to slither out of the yard while Spiegel wasn't looking, The Philadelphia Inquirer said.
Snakie is 23 years old. Boas generally live to between 20 and 30 years old in the wild.
Snakie feeds on live rats once a month, Spiegel said. Snakie's last meal came about 10 days before his escape so he's likely not hungry.
The Spiegels have alerted neighbors and local police and firefighters to be on the lookout.
Their home abuts a field where the boa could have gotten stuck in a shady area. When not in direct sunlight, a boa's metabolism drops to save energy. If in an area where sun doesn't hit the ground boas sometimes cannot summon the energy to keep moving and can die.
Snakie, though, has been through this before, the Spiegels said. The snake escaped once before and a worker at a nearby college found him, scooped him up in a pillowcase and called the family to pick him up.
Though he might give a neighbor a fright, Linda Spiegel said her family misses their pet snake.
"We just want our little guy back," she said.