Freedom for Animals said an activist who volunteered at the South Lakes Safari Zoo for nearly a year found cases of ‘animal welfare violations’.
Zoo bosses have not accepted the findings, which FFA say include a ‘disturbing reality of animal injury, illness and death’ as well as overcrowding and ‘inadequate’ veterinary care.
Following secret filming at the site, the group said it had discovered ‘numerous instances of neglect or animal welfare issues, sometimes resulting in apparent injuries and fatalities’.
One case mentioned included the drowning of a baby kangaroo in a lake within the kangaroo’s outdoor enclosure.
Freedom for Animals also claimed to have found kangaroos with lumpy jaws, a lemur with a broken arm and an emaciated meerkat with no available food or warm place to hide.
The activists are urging Westmorland and Furness Council to revoke the zoo’s licence and have set up an online petition.
Laura Walton, campaign manager at Freedom for Animals, said: “We are heartbroken to witness the continued animal suffering at Cumbria Safari Zoo.
“Despite our tireless efforts and the overwhelming evidence of neglect over the years, the council have failed to act appropriately.
“Their inaction is indefensible, and a grave injustice to the animals held captive there.
“That is why we felt compelled to carry out this undercover investigation to share the truth and to urge the council to finally revoke this zoo’s licence.
“We must bring this ongoing tragedy to an end.”
The group has published several videos from inside the zoo on its YouTube channel.
Karen Brewer, chief executive of Cumbria Zoo Company Limited, responded to the claims saying: “The organisation making these allegations is anti-captivity by nature.
“We continue to welcome feedback, advice and guidance from those qualified to comment on the way in which the zoo is run.
“We are aware of a video now in circulation that pieces together snapshots in time – many predating our running of this zoo, as do many ‘facts’ that surface in these reports.
“We have no concerns over the standard of veterinary care given to the animals who reside with us.
“Our veterinary team are internationally recognised and unrivalled in their field.”
The Zoo Investment Company, which owns the site, was not able to provide comment in time for publication.
However chief executive Janette Kemp said she wanted to reiterate the welfare of animals in the zoo was ‘of the greatest importance to myself and that of my company’.
Westmorland and Furness Council was contacted for comment.