Dozens of peacocks and peahens known for wandering the grounds of a historic Art Deco hotel in the US are missing, and the hotel staff said Tuesday they believe the birds were stolen.

After a customer at the Ryde Hotel — in northern California — mentioned seeing two men grabbing one of the birds and putting it inside a cage on the bed of a pickup truck on Sunday, the staff did a count and realised only four of their exotic birds remained, hotel general manager David Nielsen said.

“We’re not sure why anyone would do anything like this, but the staff is absolutely heartbroken,” Nielsen said.

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Authorities are investigating the case as a property crime. The male birds are valued at $2000 each and the peahens at $1000 each, Sergeant Amar Gandhi, a spokesperson at the Sacramento County Sheriff’s Office, said.

He did not share any additional information.

The owner purchased five of the birds to wander the grounds 14 years ago. They reproduced “to the point that they became a signature of the hotel”, Nielsen said.

Peacocks are common in Art Nouveau design.

Staff fed them leftovers of filet mignon, prime rib and salmon, and over time, the birds became tamer.

They got used to people, and the employees began seeing them as pets, even naming some of them.

Rafe Goorwitch, the hotel’s catering coordinator, said he fed a group of about 15 peafowls twice every day.

He named the biggest one Alibaba, Baba for short, because he would walk through the hotel like he owned the place.

“I joked with the owner that we worked for Baba because he would walk through the dinner rooms, the ballrooms and the garden with this attitude that he was the boss,” Goorwitch said.

Peacocks tend to be aloof, but Baba “became like a dog”, he said.

Since the news about the missing birds became public, people have been calling the hotel with tips and possible sightings, including reports of neighbours with new peacock pets, Nielsen said.

Hotel staff are hoping the birds are found and returned home.

For now, the hotel has added better and more surveillance cameras, and there are plans to add more fencing.

“They really meant a lot to us,” Nielsen said.