A wild fox entered an outdoor bird habitat at the Smithsonian National Zoo in Washington, D.C., and killed 25 flamingos and a duck, the zoo said Tuesday.
Three additional flamingos were injured in the attack; they are being treated at the zoo's hospital.
Staff members arrived at the habitat on Monday morning to find the flamingos dead and a fox in the zoo's outdoor flamingo yard, the zoo said. The fox escaped the yard.
The flock originally had 74 flamingos. Staff moved the remaining flamingos indoors and the ducks to a covered, secure outdoor space.
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“This is a heartbreaking loss for us and everyone who cares about our animals,” said Brandie Smith, director of the Smithsonian’s National Zoo.
“The barrier we used passed inspection and is used by other accredited zoos across the country. Our focus now is on the well-being of the remaining flock and fortifying our habitats," Smith continued.
The zoo said that staff conducts "exhibit-integrity inspections" multiple times a day.
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The last inspection of the outdoor yards on Sunday at 2:30 p.m. revealed "no areas of concern," the zoo said.
However, an inspection conducted Monday morning revealed "a new softball-sized hole in the heavy-duty metal mesh that surrounds the outdoor yard," the zoo said.
The zoo is investigating the incident.
Employees of the zoo have reinforced the metal mesh surrounding the flamingo yard, and live traps have been set around it to catch any predators.
Digital camera traps with an "infrared sensor triggered by movement" have also been set up to photograph overnight activity, the zoo said.