The howls, pitched high into the morning air, carried several possible meanings normally lost on human ears.
But two-legged listeners at the Wildlife Science Center near Forest Lake lucked out Friday, with wolf expert Peggy Callahan nearby to interpret.
The howling in this context, she said, probably meant something like: Halt, for this is my territory and you are in it.
"When you hear a wolf howl, you know that they're comfortable and feel like they're home," said Callahan, the center's executive director.
The challenge now facing Callahan is transporting the center's diverse pack of animals to a new home before the nonprofit's long-standing lease ends next month.
The scene on Friday was all bushy tails and spunky wails as Callahan and her team worked to corral, vaccinate and anesthetize 14 wolf pups for their journey to broader pastures.
The pups were among the first batch of animals moved to a new 165-acre property in Linwood Township in Anoka County's northeastern corner, which the nonprofit acquired years ago but waited to fully develop owing to the Great Recession.
The center is home to the largest population of captive wolves in North America, Callahan said. It provides science education programs each year for thousands of students from preschool to 12th grade. Wildlife professionals frequent the center for training and research, and wildlife there have been featured on Animal Planet, the History Channel and National Geographic.