Animal rights groups are calling or an investigation into the way some of Britain's leading zoos are being hired out for raucous drink and drug-fuelled parties.
Animal welfare campaigners recently caught clubbers on film taunting gorillas and hurling objects into enclosures after a three-day rave was held at the Port Lympne Wild Amimal Park in Kent two weeks ago.
The Aspinall Foundation, which owns the zoo and whose trustees include casino tycoon Damian Aspniall, hired out a large area 500 yards from their main entrance for the Zoo Project dance festival weekend.
Partygoers were free to mix with shocked young families as the rave tickets provided a free pass to the zoo.
According to the Express, three men wearing festival wristbands walked into a restricted area by the gorillas' open-air enclosure, and discussed jumping the wall to "shake hands" with the animals.
The Aspinall Foundation said: "While there was an element of unacceptable behaviour, these individuals were removed from the park and the festival site."
Back in August, it also let the Hevy Festival - featuring punk and rock bands - hire the venue, just two months after Prince William toured the zoo to back its black rhino breeding project.
The foundation says that these events raise money for vital conservation work.
And they are not the only ones doing it; London Zoo offers "Black Tie with a Hint of Animal" functions for office parties, and such events have left animal welfare campaigners worried by the noise, the rise in visitors and the greater risk of criminal behaviour.
Kent police made one arrest for Class A drugs at the recent Zoo Project festival, while investigators from the Captive Animals' Protection Society filmed a group of ravers inhaling what they believed to be nitrous oxide laughing gas balloons, and caught another group rattling gorilla cages with a stick and making ape noises.
Labour's shadow environment spokesman Tom Harris said he would be tabling questions at the Commons next month, adding: "Most people would be appalled by this. I'm shocked."
Meanwhile, last year, two dolphins at a zoo in Switzerland died a "slow and painful" death after partygoers fed them a heroin substitute at a weekend-long rave on the premises.
According to the Mirror, the dolphins, called Shadow and Chelmers, died within five days of each other in November 2011 after park bosses at the Connyland marine park in Lipperswil rented land near their training pool to organisers of a weekend rave.
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