How do you ultrasound an okapi during a global pandemic?

by ZSL on

By ZSL’s Head of Wildlife Health Services, Chief Vet Nic Masters

It’s been eight weeks since the global coronavirus pandemic caused ZSL London and Whipsnade Zoos to close their gates to the public for the first time since WW2; an unprecedented event that - though I’ve remained at London Zoo’s Vet Hospital, caring for the animals - still feels unreal.

During that time, while ZSL urgently calls on the public and government for financial support to see us through this uncertain time, our vets and vet nurses have continued to look after the 22,000 animals who call our zoos home - performing ultrasounds on Critically Endangered big-headed turtles coming out of hibernation, monitoring Bandit the golden-headed tamarin’s age-related diabetes and giving our white rhino Tuli a pregnancy test, to name just a few things on our list. 

Bandit at ZSL London Zoo

Zoo life goes on, and so must we.

All living things are capable of adapting for survival, whether that be evolving slowly across millennia or swiftly in the moment: when food shortages hit the country during WW2, ZSL staff grew vegetables for the animals on site - donating the surplus to the Ministry of Food - while repurposing our two tunnels into air raid shelters to keep our staff and animals safe.  

In these new, difficult times, the ZSL team is rising to new challenges almost daily, from working out how to continue to care for all 22,000 animals at our zoos while following guidelines to keep everyone safe, to facilitating at-home interviews about wildlife health with news organisations across the globe.

As a result, our pregnant okapi Oni recently had a routine ultrasound that was, in fact, anything but routine.

Pregnant okapi standing under a tree

Okapis were first described in 1901 by ZSL Fellow Sir Harry Johnstone, and while ZSL conservationists have worked in Africa to preserve these majestic animals - the only living relative of the giraffe - a combination of ongoing conflict in the area and their naturally shy nature means that to this day very little is known about the species.

Most conservationists have only ever seen them on camera traps, set up to track their range, so it is of vital importance that we learn as much as possible about okapis through caring for them in zoos.

Okapi camera trap image
Okapi camera trap image

Since Oni’s pregnancy was confirmed late last year, ZSL vet Tai Strike has worked closely with Oni and her keepers to perform an ultrasound scan once a month - monitoring the calf’s progress and gathering important data to share with zoos and conservationists across the world. 

But the coronavirus outbreak presented our team with a unique challenge: how do you ultrasound an okapi under strict safety measures put in place to protect the Zoo? 

When the lockdown was first announced back in March, detailed plans were immediately rolled out at both zoos to ensure our teams of keepers and vets could safely continue to care for our animals, while future-proofing in case anyone had to self-isolate.  

This involved separating London Zoo staff from Whipsnade Zoo’s - as some often work across both sites - and assigning a vet team to each Zoo to remain in place for the duration of the lockdown: at London, this also involved splitting our dedicated zookeepers into two teams  - A and B - organising rotas so that these two teams never worked at the same time. 

This ensured that if someone from Team A displayed any symptoms of Covid-19, they could be safely isolated without Team B being potentially put out of action as well. It's a system that has worked well for us so far, but with Oni’s regular vet Tai Strike assigned to Whipsnade in the split, the team had to figure out how to continue Oni’s ultrasounds at London without her.  

To further complicate matters, due to the team split, as London Zoo’s Team B vet, I wasn't scheduled to work the same days as Oni’s main carers, Team A’s Gemma Metcalf and Megan Harber, who have patiently worked with Oni over many months to ensure she was totally at ease with the procedure.  

But where there’s a will, there’s most definitely a way. For the past few weeks I have had regular meetings with Tai via video link, getting up to speed on Oni as an individual and how her pregnancy has progressed so far. 

Oni the okapi’s six-month scan

At the same time, Gemma and Megan have trained their Team B colleague Holly Dorning via Facetime on how to make sure Oni is in the right position for the ultrasound, what treats she likes to have during the procedure - brown bread has been Oni's strongest pregnancy craving, apparently - and how to support the vet team while they carry out the ultrasound.  

This takes strong arms, as the ultrasound gel - which Oni loves to lick off - needs to be rubbed into her belly for a good ten minutes to get a clear picture, before the ultrasound machine is held steady for the 45-minute procedure.   

All while everyone involved is in PPE and attempting to remain two metres apart. Are your brains (and arms) hurting yet? Quite... 

In late April, after numerous practice runs, Gemma, Megan and Tai supervised via video link as Holly and I carried out the ultrasound. And at just over nine months along I can confirm that Oni’s baby is healthy, has a strong heartbeat and is due sometime in September.

I am immensely proud of everyone involved for overcoming this hurdle, and many more like it every single day, in their unwavering dedication to our animals - many of which, like Oni, are threatened in the wild and part of important global breeding programmes which rely on zoos such as ZSL’s to continue. 

The whole country has had to adapt to face our shared new reality, and the ZSL team - while exceptional - is no exception.

And while we remain closed to the public, we’ve maintained a steady stream of zoo news via our website and social channels, helping people remain connected to the wonders of the natural world during these difficult times.

But the Zoo is now fast becoming endangered itself -  ZSL is a charity and every day that we are closed is another day’s worth of funds we must somehow find to keep our two Zoos running smoothly, our scientists investigating wildlife diseases such as Covid-19, and our conservationists working in the field to protect critically endangered species.  

The future of this iconic national institution now hangs in the balance: as well as asking the government for support, ZSL has a live public appeal at - every donation makes a difference. 

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