Whipsnade Zoo 'heartbroken' as one-horned rhino put down

Whipsnade Zoo's two female greater one-horned rhinos, 29-year-olds Behan and Beluki, were found to have growths and cysts in their reproductive organs, which is common for older female members of the "vulnerable" species.

After receiving an immune-contraceptive vaccine twice a year, specialist vets from the Leibniz Institute for Zoo and Wildlife Research (IWZ) in Germany were flown in this week to put both animals under general anaesthetic to check how the treatment was working.

Vets draw blood from Behan as part of the health checks. (Image: Whipsnade Zoo) But staff were “deeply saddened” to find Beluki’s tumours had not been affected by the vaccine, although her condition had been more advanced when diagnosed.

The growths had advanced to the point of being inoperable and the decision was taken not to wake the 29-year-old rhino from the anaesthetic to prevent further suffering.

Although the scan saw a negative result for Beluki, it also revealed that the other rhino Behan’s previously large tumours had almost entirely disappeared following the treatment.Scans revealed that Behan's tumours were almost invisible following the vaccine. (Image: Whipsnade Zoo) Senior veterinary officer Taina Strike said: “Today has been an incredibly bittersweet day for Whipsnade Zoo.

“While Behan’s remarkable recovery has given us all hope, we and her dedicated keepers are heartbroken by the loss of Beluki, who has lived at Whipsnade Zoo since 1998.

IWZ speciaist vet Susane Holtze and staff gather to check the scan results. (Image: Whipsnade Zoo) “During the ultrasound examinations this week we found a marked difference in the conditions of both rhinos. Beluki’s tumours were inoperable and impacting other organs, meaning her quality of life was only going to deteriorate - the kindest decision we could make was to euthanise her.” 

The rhino will undergo a postmortem to understand why it responded differently to the treatment and inform future conservation efforts.

It comes after Moto, the king of the lions at Hertfordshire Zoo in Broxbourne, passed away in July at age 17 "after battling age related health issues".

Regarding Behan’s recovery,  Dr Strike added:  “We went into the procedure prepared for multiple outcomes, but I don’t think any of us was expecting to see such an incredible result for Behan. 

The scan revealed that Beluki's tumour had not been affected by the vaccine treatment. (Image: Whipsnade Zoo)

“The tumours are almost invisible on the scan, and the ovarian cysts have completely disappeared.”

“We will continue to closely monitor Behan as she gets older – but for now, the ongoing treatment is working and we’re delighted that we’ve been able to put her condition into remission.” 

The zoo estimated there are 3,700 greater one-horned rhinos left in the wild, but efforts by the ZSL charity, which runs Whipsnade, have seen their number grow by 17 per cent in recent years.