Abstract. - On the skin surface of delphinids small biofoulers are challenged to high shear water flow and liquid-vapor interfaces of air-bubbles during jumping. This state of self-cleaning is supported by the even, nano-rough gel-coated epidermal surface of the skin. In the present study we focussed on the topographic evolution of gel formation and the chemical composition of the gel smoothing the skin surface of the pilot whale, Globicephala melas. We employed photoelectron spectroscopy (XPS) in combination with cryo-scanning electron microscopy (CSM), and transmission electron microscopy (TEM).In the superficial layer of the epidermis, stratum corneum, intercellular material was shown by electron optical methods to assemble from smaller into larger covalently cross-linked aggregates during the transit of the corneocytes towards the skin surface. Employing XPS measurements, the surface of the skin and the intercellular gel included in approximately the same amount polar groups (especially, free amines and amides) and non-polar groups corresponding to the presence of lipid droplets dispersed within the jelly material.It was concluded from the results obtained that the gel-coat of the skin surface is a chemically heterogeneous skin product. The advantages of chemically heterogeneous patches contributing to the ablation of traces of the biofouling process are discussed.