Little bee-eater (Merops pusillus) in the midst of scratch preening over the wing with its bill pointing straight up. Scratch preening or head scratching helps birds in applying preen oil to the head, reducing parasitic organisms and contributes to maintain waterproof plumage. This capture is enhanced by the compositional elements: the vertical imaginary line drawn by the bill pointing straight up contrasts with the curvilinear shape of the perch.