When tear-jerking BBC1 wildlife series Dynasties showed lioness Charm giving birth to two cubs they represented hope that the Marsh Pride’s future was safe at last.
But neither of the youngsters survived, the film-makers have discovered.
A show insider said: “The most likely explanation is that they were taken by hyenas or another predator or even trampled by buffaloes.
“No one can be sure, but what became clear was they were no longer with Charm, and there was no way they could have survived alone at a few weeks old.”
Viewers were delighted when Sunday’s harrowing episode ended with the arrival of the newborns.
It was months after two members of the pride were killed in a poisoning and several young females were forced out by incoming males.
Charms cubs failed to make it to adulthood
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Charm’s new cubs, a male and a female, were born after the matriarch endured an 18-month uphill struggle.
The film showed the perilous start in life faced by the youngsters, who were born away from the pride and only introduced to the others at six weeks old.
They failed to survive despite 15-year-old Charm’s experience at rearing cubs, and the protection of their father and another adult male.
The BBC team made the discovery a few weeks after the end of the period covered by the film in Kenya.
But the pride has managed to thrive since the deaths. A few months later Charm had another two cubs, and her eldest daughter had a litter of three.
Charm’s filmed cubs died but she went on to raise another two
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Film-makers have also revealed that another pride, led by six males, moved into Charm’s territory.
To avoid conflict, she led her group north to an adjoining reserve in the Masai Mara. They were last spotted raising their cubs successfully.
Up to four out of five lions die before the age of two. In Kenya, where the creatures face a battle for space with humans, the 2,000-strong population is thought to be falling by 100 a year.
Dynasties, narrated by Sir David Attenborough, is a five-part series with each episode featuring a different endangered animal, including chimps.
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