A couple who took their nearly 5-foot boa constrictor for a swim in a Pennsylvania river say the pet slipped away and they’re concerned about its welfare.

The Bloomsburg Press Enterprise reported that Kolby and Zachary Latranyi had been swimming with the snake named Leyla one August weekend in the Susquehanna (suhs-kwuh-HAN’-uh) River. The Latranyis say the red-tailed boa was shedding, so the swim was designed to help it remove material from its scales.

They say Zachary Latranyi was on shore with the snake wrapped around his shoulders when he dozed off, never noticing that Leyla had slithered away. They’ve been back to the riverside several times, but so far haven’t turned up the missing reptile, who is reportedly “very friendly.”