DOES my rump look big in this? A scientist has gone undercover in a 14-stone armoured hippopotamus suit in Zambia to mingle unremarked with pods of the feared mammals.

Dr Brady Barr, who returned from his mission last week, adopted the disguise in an attempt to harvest sweat samples from hippos in the quest for a new type of sun cream.

The suit, designed by a taxidermist from the Smithsonian Institution in Washington DC, consists of a steel-ribbed tube wrapped in bulletproof material and topped with mouldings taken from a female hippo.

“I have long believed that hippo sweat can provide breakthroughs in waterproof sunblock and antiseptics,” said Barr. “It works for them in some of the harshest environments in the world; it could work for us. But extracting it did not prove to be as easy as we hoped.”

Most of the weight in Barr’s suit is in the body armour. It is able to withstand a bite three times as powerful as that of a great white shark. Hippos cause more human deaths than any other animal in Africa.

When reassembled in the African bush, the suit was finished off with a daubing of mud and dung to disguise the scent of the scientist staggering beneath it to the riverbank to await a passing hippo. Barr’s plan was then to open a flap, tap a hippo with a long pole and scoop off fresh drops of its sweat.

He and his colleague, Christopher Viney, 48, a bio-engineer born in Skegness, arrived in Luangwa national park with high hopes of becoming the first scientists to extract the blood-red sweat of a wild hippopotamus before it dried brown.

Why? “Because the sweat, or to be more exact secreted oil, is denser, with more complex molecules, than the sweat I collected from Bulgey the hippo who lived in a zoo near where I teach,” said Viney, professor of engineering at the University of California, Merced.

On the first day in Luangwa, the fake animal was ignored, except by a curious lion, which sniffed and passed by, and a juvenile elephant, which mock-charged.

“I was bent double in 100F heats and the stench was eyewatering,” said Barr, 45, after six hours in the suit. His task will be seen on a documentary to be broadcast on Nat Geo Wild TV channel in April.

The most dangerous day was when the hippo suit started sinking into mud, eyed by a lone male a few feet away. A park ranger called Boston Chulu risked his life trying to squeeze Barr through an escape hatch, but it jammed. The scientist had to crouch inside sweating until the real hippo became bored and wandered off.

His mission failed but, Barr said, “we shall be going back to Africa as soon as we can”.

To see video of Brady Barr pretending to be a hippo, click here

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