Screenshot of lions pacing at Bristol Zoo
Screenshot of lions pacing at Bristol Zoo. Animal rights campaigners say the pacing showed the lions were stressed by the late night party held at Bristol Zoo. Caps Campaigns / YouTube

Animal charity the Captive Animal Protection Society (Caps) has released footage that it claims shows animals being "stressed" by a late night event at Bristol Zoo. The undercover video shows lions pacing back and forth as revellers party to loud music in the zoo grounds.

Caps campaign director, Nicola O'Brien said: "The zoo continues to state that it has the animals' welfare in mind, yet a member of staff has openly told the investigator that the event was causing the lions stress."

In the video a staff member can be heard saying that the event "does stress them out a bit" after being asked why the lions are pacing.

"With an event like tonight, because there is so much going on that is unusual for them," says the staff member. "Obviously normally there's not music, normally there's not people here at 10 o' clock at night, it does stress them out a bit so they're just keeping an eye on what's going on and they are more prone to stereotyping, so pacing".

The charity also said that residents two miles from the zoo had complained about the noise level on Facebook.

Bristol Zoo refuted the campaigners' claims, saying that the lions "were categorically not displaying signs of discomfort" and that the member of staff heard speaking in the video was "not a qualified zookeeper".

The zoo said that because the lions were rescued at a young age, they have a "mother" association with their keepers and that was why they paced: "The pacing seen in the footage was in anticipation of seeing someone they knew and not as a result of sound levels."

Around 1,400 people were at the event, said the zoo, and guests were monitored by "a strong staff and security presence".

Caps called for the end of late-night events at zoos. "This is not the first time we and others have documented the negative impacts of these night time events on animals yet zoos continue to put their animals at risk," said O'Brien. "The only way to prevent this happening again is to end them once and for all. If zoos really care about animal welfare, they will stop organising these events."

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