A lion has been caught grinning from ear to ear before mating with a lioness in the Maasai Mara National Reserve in Kenya.

The photos show the big cat in highly animated states of arousal; standing on its hind quarters, roaring and baring all its teeth as he prepares to mount the lioness.

Photographer, Vclav Ilha, 55, said: ‘As soon as the female is ready to mate, she would raise her tail and provoke him by rubbing him or crawling at his feet. The male follows her impatiently, for the female leaves behind a strong odour.’

This was just the beginning of a session that could last up to five days; lions will mate up to 200 times and despite the act lasting just a few seconds, they will continue to mate after 20 minutes.

Rampant: The lions rocks back on its hind quarters as it grins down at the lioness who looks back at him, lying on her back, as the pair prepare to mate in Maasai Mara National Reserve in the south east of Kenya

The lion bears its teeth as it sits at the rear of the lioness on the grassy plains of the Maasai Mara National Reserve in Kenya; although mating itself takes only a few seconds, it is repeated about every 20 minutes

The lion roars and the female roars back at him as he prepares to mount; when lionesses are ready to mate they will raise their tails and stimulate males by rubbing or crawling at their feet

The young male shows its fangs as its front legs stand either side of the female’s rear; a male lion will follow a lionness impatiently as she trails a strong odor behind her when she is in heat

A grin or perhaps a grimace as the lion prepares to mate with the lioness in the soft evening sunset light of the Maasai Mara; the nature reserve is globally exceptional for its large lion, leopard and cheetah populations

The lion’s face is scrunched in anticipation or frustration as it flexes above the lioness who growls back at him from the ground; lions do not mate at a specific time of year and the females are polyestrous, meaning they can go into heat several times throughout the year

The lion roars with its jaws wide and showing massive fangs as it stands astride the lioness who roars back at him; photographer, Vclav Ilha, 55, said: ‘I like my photos to capture some interaction. Whether among animals, nature or advancing civilization’

The look of love: The lion’s face is contorted with desire as he looks down at the lioness on the savanna floor looking back at him; their session could last several days and include up to 200 separate acts of mating