First brown bear to undergo brain surgery emerges from semi-hibernation

A brown bear which underwent pioneering, life-saving brain surgery in October has emerged from semi-hibernation “looking brilliant, happy and healthy”.

Three-year-old Boki, who lives at Wildwood Trust, near Canterbury, Kent, had been suffering from seizures which were believed to be caused by hydrocephalus (fluid on the brain).

He had been medicated with prednisolone to deal with the swelling and build-up of fluid, but zoo staff would have been unable to treat him once he went into torpor (semi-hibernation).

Brown bear Boki in his enclosure at the Wildwood Trust in Kent after waking from semi-hibernation as he continues his recovery from surgery to drain fluid from his brain (Gareth Fuller/PA)PA Wire/PA Images - Gareth Fuller

It was decided that brain surgery was the best option for Boki and he went under the knife for five hours on Wednesday October 9, making him the first brown bear on record to have brain surgery.

World-leading veterinary surgeon Romain Pizzi, who waived his fee for the job, fitted a stent between Boki’s brain and abdomen to help pass the excess fluid.

A spokeswoman for Wildwood said the bear has made a “remarkable recovery” and was weaned off his medication with no adverse effects just before he went into torpor.

Head of bears at Wildwood Jon Forde said Boki’s emergence from semi-hibernation is a key stage in his recovery.

He said: “He’s looking brilliant, happy and healthy and we haven’t seen any negative signs from him. All his personality traits are still there – he’s still the same old Boki that we love.

“Boki did well for his first ever winter sleep. He lost around 30kg – we think a lot of this because he’s actually grown while he was asleep so a lot of energy has been used for that.

“Our first job will be to put some weight back on him. At this time of year there’s not a lot of food around – mostly vegetation – so we’ll get some weight back on him but start him slow and take our time and make 100% sure he’s healthy.”

Boki being prepared for surgery to drain fluid from his brain in October 2024 (Gareth Fuller/PA)PA Wire/PA Images - Gareth Fuller

Boki had been adopted from Port Lympne Wild Animal Reserve in December 2022 after he was rejected by his mother and had to be hand-reared by keepers there.

The spokeswoman said: “The team at Wildwood, renowned for their work with brown bears, had to help him learn bear behaviours. As part of this work, they had begun to integrate him with their two adult bears – Fluff and Scruff.

“This had to stop with the onset of his seizures but the hope is that they’ll be reunited in the not too distant future.”

Wildwood’s head of zoo operations Mark Habben said: “What a remarkable transformation we’ve seen in this young bear – he’s back to being the Boki we first met. It’s like he’s forgotten that he even had an operation.

“While the signs are very positive, we still need to proceed with caution and to take care with the reintroduction to Fluff and Scruff.

“This will involve boisterous play, which we want to minimise in these early stages post-torpor.

“We will monitor him very closely and, at some point over the coming months, we will conduct that introduction if everything continues to go well.

“We have to take this step for his wellbeing and theirs as well – they want to be together.”