I posted a link to your picture to the reptile section of a taxidermy webpage. I assume it was a male and female but a poster said the following:

Neat photos but I would say that it is 2 male snakes in combat rather than mating. The male snakes will raise up like that, rap around each other and then push each other down to the ground. When mating the snakes will lay next to each other like that but be flat on the ground with their tails turned against each other.

If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.