Hope the whale at the Natural History Museum

At the heart of the Natural History Museum is Hintze Hall, a magnificent cathedral-like space that thousands of visitors pass through every day.

Since 1881, many different specimens have called this space home. Whether it be George the African elephant, a 300-kilogramme coral or the iconic Dippy the Diplodocus, these precious objects have all wowed visitors over the years while telling important stories about life on Earth.

Choosing a new star specimen to join this exclusive line-up was no mean feat! The chosen specimen would have to have the wow factor, both for first-time visitors and for those visiting time and time again. It also needed to have a strong scientific message!

In the end, Hope the blue whale was the obvious candidate. The wonder at walking beneath the largest animal on Earth never fades, while the recovery of blue whale populations in the wild is a vital reminder that we can save the planet and all the amazing species that call it home if we all work together.

Unveiled to the public in Hintze Hall in 2017, Hope has rapidly become a favourite with visitors. Discover how a team of conservators, engineers and scientists managed to give this enormous animal pride of place in the Museum.

Putting Earth’s largest animals on display

When we purchased Hope’s skeleton in 1891, our building in South Kensington had only been open a decade. Since the Museum’s inception, the idea of putting a whale on display had been circulating.

Sir Richard Owen, our founder, had even put the idea of publicly displaying a blue whale at the heart of his proposals.

“The very fact of the whales being the largest animals upon the Earth, is that which makes it more imperative to illustrate the fact and gratify the natural interest of the public by the adequate and convenient exhibition of their skeletons,” he said.

Sir Richard retired in 1883, so it was up to his successor Sir William Henry Flower to fulfil that dream. A sperm whale was put on display in Hintze Hall during his time as Director, with visitors able to walk around the skeleton at ground level.

Sir William also spearheaded an extension to our building that – following decades of funding problems, politics and the First World War – eventually became a dedicated hall for whale specimens in the 1930s.

This new gallery, now known as the Mammals Hall, finally had the space to put Hope’s 25.2-metre-long skeleton on display. However, having been in storage for more than 40 years, there was plenty of work to do to make her ready for her adoring public.

One crucial feature of the skeleton that needed recreating was the cartilage discs that sat between the back bones. These had been removed when Hope’s skeleton was originally prepared. To ensure that the bones were accurately spaced when hung from the ceiling, simple and lightweight replacements were needed.

In the end, the replacement discs were made from whatever the technicians and preparators could lay their hands on. Wooden blocks, plaster of Paris and even newspapers were used to space the bones apart.

Eventually, after a great deal of work, Hope was hoisted high above the Mammals Hall and made her public debut with our visitors in 1934. It was here she would stay for 81 years.

Hope’s hidden secrets

Following the decision to relocate Hope to Hintze Hall, and after months of planning, work on the project began in October 2015. Scaffolding was erected around the skeleton so that Richard Sabin, our Principal Curator of Mammals, and Lorraine Cornish, our then-Head of Conservation, could begin inspecting the 221 bones.

“The deconstruction and rebuilding of this skeleton is, I think, the largest project of its kind the Museum has ever been involved in, so it was important to do it right,” Richard says. “Our examination was probably the most detailed inspection that these bones had ever had.”

“By getting up close to the skull, we could see that parts were cracked after hanging from the ceiling for decades. We needed to make sure that we could deal with that, because the entire move hinged on the condition of the skull.”

There were also questions about the state of the rest of the skeleton, which was hidden under a “lunar landscape” of dust that had built up over 81 years. Fortunately, following some careful hoovering and inspections by the Conservation Team, the whole skeleton was found to be stable enough for the move to begin.

While the bones were carefully taken down from the mount one by one, the dust went on its own journey. Parts of it were kept for the collection, while other samples were tested to reveal a rich community of yeasts and other fungi. These species had previously been found in all kinds of places, from Alpine glaciers to northern Siberia!

Other parts of the mount came from much closer to home, such as the newspapers that were used to pack the replacement discs. These were carefully unfolded by the team and included pages from the Kent Messenger and St Pancras Gazette. They’ve been kept as artefacts and are now stored in our archive where they can be read for the first time in decades.

The bones, meanwhile, were each carefully wrapped and prepared to be moved. Smaller bones were taken to our Conservation Studio, but the skull was so big that it had to be taken to the only space big enough – our offsite store.

It was then time to give the skeleton a thorough clean. Whale bones contain oil, which in life helps them to maintain their buoyancy in the oceans. Once a whale dies, this oil gradually leaks out over time, and, more than a century after her death, Hope was still leaking.

To try and remove as much oil as possible, the team swabbed the bones with ethanol and then left them to dry. They kept repeating this process until the bones stopped becoming sticky, at which point more effective cleaning could be carried out.

This process revealed more hidden features, including hairline cracks that had previously been clogged with oil. These issues were noted down for fixing as conservation of the skeleton continued.

“By this point, we already knew where the really strong parts of the skeleton were, and which were really fragile,” Lorraine adds. “As the conservation work continued, we learnt more and more to help prepare for the next stage of the move.”

Scanning Earth’s biggest animal

After Hope’s bones had been thoroughly cleaned, the team took the opportunity to 3D scan the entire skeleton. Using a mixture of handheld and fixed scanners, the team digitised the whale over the course of six months.

Eventually, the team had a virtual blue whale skeleton that they could examine in extraordinary detail. It helped to reveal further cracks and other issues that were invisible to the naked eye, giving conservators a chance to fix them.

Hope was then relocated again, this time to a specially adapted aircraft hangar outside London for lidar scanning. This process uses light to measure the position and distance of objects. Engineers used it to plan how to suspend Hope above Hintze Hall.

Using the scans, they 3D printed a 1.5-metre-long scale model – almost 17 times smaller than the real Hope. They then used this to test how different positions would work without having to rearrange an entire blue whale skeleton.

Richard took the lead on Hope’s new pose. He decided to focus on lunge feeding, where blue whales take in huge mouthfuls of water and filter out food using the baleen plates in their mouths.

A lot of what scientists know about this behaviour comes from data-logging devices, which are attached to blue whales using suction cups. These reveal information about the depth, angle and acceleration of dives, but there’s only so much they can show.

So, Richard flew out to California to see blue whales in their natural habitat. He joined the Cascadia Research Collective, who have studied these animals for decades, to try and witness lunge feeding in the wild.

One day, as Richard’s boat emerged from a bank of fog, the team found themselves alongside a blue whale. Through the clear waters of the northern Pacific, Richard saw just how the animal arched its body as it slipped beneath the waves.

After watching multiple whales dive in the same way, Richard was ready to design how Hope’s new pose would look. He sketched out his idea and, following rigorous testing with the scale model, got it approved.

Now the design was settled, engineers started creating a 25-metre-long mount to hold all of Hope’s bones safely and securely in place. This bespoke structure was carefully built over many months, with each piece being crafted by hand.

As well as helping these talented craftspeople, the scans of the skeleton are helping scientists to study blue whales. These animals are difficult to observe in the wild, so this virtual model allows researchers all around the world to answer questions about the bodies of these enormous creatures remotely.

For example, 3D scans can help scientists to understand how a whale manages to open and close its mouth under the intense pressure of the ocean. Combined with knowledge of their muscles and observations of how they feed, scientists can use the data to build models of the jaws that reveal how the skeleton copes with the extreme forces involved.

CT scans taken from Hope’s last eight tail bones, meanwhile, provide crucial information about their internal structure. This tells scientists about the stresses the tail can cope with, and how that affects the way blue whales move through the water.

Hope’s homecoming

Eventually, nearly 18 months after she was moved out of our Mammals Hall, Hope was ready to enter her new home. But there was one big issue – how do you get a six-metre-long skull through the doors of a Grade I listed Victorian building?

The answer? Turn it on its side! Even then, Lorraine says that the move still wasn’t easy.

“The biggest challenge was getting the six-metre skull through the front doors,” she explained. “After meticulous planning and measuring, we knew that there would be only a few centimetres to spare. The front doors would need to be removed.”

So, the doors were taken off their hinges and a scaffolding platform created on top of our front steps. Then, a packing crate containing Hope’s skull was carefully moved into place. It was crunch time for the entire move project.

“The crate was slowly wheeled along the platform towards the front entrance, and we gently pushed and pulled it through the gap,” recalls Lorraine. “Once it was successfully in Hintze Hall, we turned the crate back to a horizontal position.”

“The whole process took several hours, running into the early hours of the following morning. Everyone breathed a collective sigh of relief once it was safely delivered.”

While the skull underwent final conservation work, the rest of the skeleton was about to become part of one of the world’s biggest jigsaws. Each bone was carefully attached to the mount and locked into place.

During the install, the team also left their mark on the skeleton. When Hope was originally put on display in 1934, project staff signed their names on the back of the skull. In honour of that moment, Lorraine, Richard and other staff involved in the project left their signatures too.

Finally, after the enormous lower jaw bones were fixed into place, Hope was ready to rise. The skeleton was slowly raised over a few days to make sure that everything was as it should be, until she eventually reached her new home high in Hintze Hall.

Hope by name, hope by nature

On 13 July 2017, Hope was ready to be revealed to the world. Joining her in the refreshed Hintze Hall were 10 other star specimens, including fossilised trees, an American mastodon and a remarkably complete Mantellisaurus skeleton.

That evening, the specimens made their debut at a star-studded launch attended by our Patron HRH The Princess of Wales and Sir David Attenborough, among others. Hintze Hall was then reopened to the public the following morning, with Hope ready to greet the first of many visitors.

Richard hopes that people will have the same reaction as he did when he first saw Hope as a 10-year-old in 1976. Seeing her skeleton in the then Whale Hall put him on a path to the career he has today.

“I remember visiting the Museum as a child and being amazed when I came face-to-face with Hope,” Richard remembers. “In her stunning new home, she’s even more spectacular. It’s impossible not to be struck by the sheer scale and majesty of this beautiful creature as she dives towards you when you enter the Museum.”

“My first encounter with the blue whale skeleton became a defining moment in my life, and I’m sure Hope will inspire a new generation of visitors.”

Hope also represents a positive message in uncertain times. In the 1800s there were an estimated 250,000 blue whales across the world’s oceans. By 1966, however, just 400 survived following decades of commercial hunting.

With the species on the brink of extinction, the International Whaling Commission banned the hunting of blue whales. Though the species is still endangered, blue whale populations have recovered since then to around 20,000.

If we can work together to bring back the world’s largest animal from the edge of extinction, then we can prevent the loss of countless other species too. Our mission, whether we’re studying little known species or inspiring the next generation, is to make that vision a reality.