The identity of this model unknown, but he is also the subject of a fine portrait study in the Detroit Institute of Arts. Perhaps Copley altered the figure to serve as a reference to the Caribbean locale. It is also possible that figure may have been changed at Watson's insistence, based on his personal recollection of the event.

Left: John Singleton Copley, Head of a Negro, 1777/1778, oil on canvas, 53.3 x 41.3 cm. The Detroit Institute of Arts, Founders Society Purchase, Gibbs-Williams Fund. Photograph © 1986 The Detroit Institute of Arts. Right: John Singleton Copley, Watson and the Shark (detail), 1778. National Gallery of Art, Ferdinand Lammot Belin Fund 1963.6.1