The air is warm and smells of spring. Plants are flowering again, bees pollinating, birds breeding, and you – well, you’re feeling a little frisky. It’s natural. “Our senses have been sharpened by the deprivations of winter. We take notice of the longer daylight hours, the flowers, birds, sun – we’re glad the lovely season has begun,” says Dr Heike Melzer, a Munich-based couples and sex therapist. This seasonal transition stimulates our bodies into releasing the “happy hormones” dopamine and serotonin, boosting libido, she says. Which doesn’t necessarily bump up the ol’ rumpy-pumpy though, par…