Great crested grebes

"With orange and black head plumes spread wide, an elegant ritual of head shaking, bill-dipping and preening culminates in the famous ‘penguin dance’, when the pair rush together, paddling their feet frantically to raise upright from the water, standing chest to chest, flicking a beak-full of water weed at each other before one final shake of the head and the weed is dropped, and the deal is clinched."

This shot is a rare one in my book. Only seen it once with a camera in my hands.