She pauses for a last look, and then without a backward glance swims across the world's fifth longest river.
Mother bear swims across the Yenisei river. Picture: The Central Siberian Nature Reserve
There is a saying that a mother's instinct is never wrong, and these pictures capture the moment a female bear bids farewell to the two cubs she has raised from birth. This is her final maternal duty, like a bird nudging her fledglings out of her nest, to send her children out into the Siberian forest and taiga all alone.
It is her conscious choice, or so it seems in these images.
She does it in a clever way: choosing a spot on the Yenisei River bank for her last farewell to her offspring, then surprising them by plunging alone into the cool waters and slowly but determinedly swimming across to the other side. It appears that she knows from intuition that her cubs - around one and a half years old - are still not strong and confident enough to swim across the river and follow her.
And her scent will be gone forever.
We are privileged to witness this natural ritual.
They watch her ears sticking out from the water, getting smaller and smaller, but they do not track her into the river. Of course, they wait by the water's edge, hoping in vain she will return. They both return together the following day, but she has long gone, knowing these cubs must survive on their own wild, and that she has done all she can to help them.
The cubs waited for the mother for two days before giving up and disappearing into the woods. Pictures: The Central Siberian Nature Reserve
The remarkable pictures were taken by an inspector from the Central Siberian Nature Reserve, in Krasnoyarsk region, who says he had not previously witnessed the moment a mother bear judges her cubs are ready to live own lives.
'I've never before seen a bear family breaking up,' he said. 'I was patrolling when I noticed a family of brown bears, a mother and two cubs. She had brought them to the bank of the Yenisei River.
'They stood together for a brief moment and then the mother went into the cold waters of the river, leaving her cubs behind.
'She crossed it and disappeared on the other side.'
The cubs waited for the mother for the rest of day, the inspector said, and he noticed them return to the same spot 24 hours later before finally giving up and disappearing into the woods.
He concluded the mother knew precisely what she was doing.
The family together for the last time. Picture: The Central Siberian Nature Reserve
There are some 250 brown bears living at the Central Siberian Nature reserve.It is one of the largest forest reserves in the world, covering over 60 kilometres of the Yenisei River on both banks, and also Podkamennaya Tunguska River valley.
The protected area covers more than one million hectares.
The bears are the largest group of predators in the reserve, yet seeing them so close was unusual since they avoid people.
'Brown bears are not very fertile, they usually have cubs every two-to-three years and quite often not more than twice in a lifetime,' said the inspector.
'Mothers breast feed cubs until June or July, depending on how quickly they start eating independently.
'Families usually break up when the cubs reach one and a half or two years of age.'
These cubs seemed to be at the younger end of this spectrum.
The bear cubs' footsteps and the Central Siberian Reserve market on the map of Russia. Pictures: The Central Siberian Nature Reserve, The Siberian Times
The Central Siberian Nature Reserve is some 700 km north of the city of Krasnoyarsk, the regional capital.
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