Twycross Zoo Tragic Chimp Deaths

Following media reports of chimp deaths at Twycross Zoo in 2015 and other queries – a note from the Zoo…

We wish to make a full statement for the benefit of all supporters of Twycross Zoo, so that you hear the full facts from us directly and do not have to rely on media reports alone.

On the early morning of 23rd September 2015 two chimpanzees were discovered by the keepers to have died overnight. Our chimpanzee enclosures are heated to mimic the natural environment of the chimpanzee home range in Africa and it was noted to be hot in the house that morning.

The electrical system was checked and a faulty thermostat was detected and replaced. Following the tragic deaths of our chimpanzees Kip and Jolly, we thoroughly investigated this incident at the time and conducted full post-mortem examinations. The professional pathologist did not draw a conclusion as to the cause of death, but noted that age-related heart disease was present.

An expert review later commissioned by the Local Authority concluded ‘heat stress was a contributory factor’ and we of course accept that review. However, we ask you to note that this expert review by the Local Authority concluded that ‘…the thermostat failure…could not have been predicted and there were no reasonable measures that the Zoo could have taken to prevent the incident’.

Twycross Zoo was always completely open in its communcations with third parties, including the media and with Zoo staff. In fact, we were complimented on our full cooperation with the authorities during their investigation of this incident, clearly showing we did not attempt to hide anything.

We also reported their deaths on our Facebook page, and as you can appreciate the staff were also upset at the loss of Kip and Jolly, and we were all touched by the sympathy of the public during that difficult time.

What has been done to ensure a repeat event does not happen again?

  • This was a tragic accident, (resulting from the unpredictable failure of a thermostat), causing heat stress in animals already affected by heart disease which contributed to their deaths. The thermostat itself is meant to act as the ‘failsafe’ for the system. However we have since fully reviewed our heating systems and keep them regularly inspected and maintained as you would expect. In this case, the heating system had recently been reviewed and upgraded; again, making this a tragic incident, but one that was not caused by negligence or poor maintenance.
  • Since then thermostats have all been modified to prevent accidentally increasing the temperatures in animal enclosures. This was not the reason for this accident, but a modification, added as a further safety measure since the incident in 2015.
  • As standard practice, daily temperatures are taken of animal areas and are fully documented. This was always the case, which had led to the thermostats being recently replaced prior to the incident; it still however malfunctioned, leading to this tragedy.
  • All hot surfaces across the zoo have been reviewed to ensure none get to a temperature likely to cause burns.

There have also been journalist questions about cockroaches and rats (referring to a complaint made in 2015).

We have a contract with a major national pest control company. We recognise that, as a large rural site with heated animal houses and natural feeding methods, it is very difficult to fully exclude pests, but we routinely use a professional company to control unwanted wild animals such as rodents and cockroaches, as much as is practically possible.

We hope our visiting public, and supporters of Twycross Zoo, will appreciate the high standards of care and attention we deliver every day in protecting the health and welfare of the animals under our care. We are always happy to answer queries and be as open and transparent as possible. Our staff and partner organisations work tirelessly to ensure the animal care and facilities at Twycross Zoo are of the highest standards and continually improving.



Twycross Zoo is a member of BIAZA – the British and Irish Association of Zoos and Aquariums; the professional body representing the best zoos and aquariums in Britain and Ireland.

BIAZA have issued a blog which addresses the zoo licensing system and highlights how this type of sensationalist reporting does not provide a true picture of the state of our zoos; read it here >

You can find out more about BIAZA’s work here >





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