Maybe I'm a bit of a perv; I love looking at photos of birds mating.
My interest was piqued a few years ago by two avian couples. One couple were Morning Doves. When we were out on our deck for happy hour with glasses of wine we could observe the pair fornicating at the top of the very steep roof.
The other were Red Tailed Hawks. I got the thrill of observing them in death dive mode, mating all they way. Imagine if you were a hawk. You have to locate your intended, climb aboard, then dive just short of the ground, successfully completing insemination on the way.
I really like using source photos of birds in love because it focuses the composition of the scene. But also because it requires that I research each species' mating rituals which varies significantly. Some, like the hawks, mate while airborne. Others, like Prairie Chickens, herons, and turkeys engage in elaborate displays and dancing. The doves we observed did their little dance atop the roof then did the deed while balancing precariously. They didn't seem to mind the level of difficulty because they had sexy times in that spot every evening.
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