It happened sometime overnight Sunday into Monday at the Oley Dairy Turnpike Zoo.
"So they pulled back the screen and ripped it," said Julie Stewart.
The thieves snatched exotic birds, including a 20-year-old African gray parrot, a sun conure named Sunny, and a pair of yellow-headed Amazons named Romeo and Juliet.
"They are worth a lot of money, I would say, on the black market," said Stewart. "Couple hundred dollars each at least."
There is what appears to be human blood drops, and it's possible the fiercely protective Romeo or Juliet drew blood from a thief.
After that, the bad guys may have avoided Rosie, a scarlet macaw.
Admission to this petting zoo is free, and it has been a delight for children for generations.
The fact someone would come here and steal infuriates owner Darleen Moser, who hand-raised the birds.
"I am glad that one bird got 'em," she said. "Whoever took them has an injury. Definitely. They were a breeding pair and a breeding pair can be really nasty."
Anyone with information is asked to call the Oley police department.
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