A Theory for the Hydrodynamic Origin of Whale Flukeprints
Whale flukeprints are an often observed, but poorly understood, phenomenon. Used by whale researchers to locate whales, flukeprints refer to a strikingly smooth oval-shaped water patch which forms behind a swimming or diving whale on the surface of the ocean and persists up to several minutes. In this paper we provide a description of hydrodynamic theory and related experiments explaining the creation and evolution of these “whale footprints.” The theory explains that the motion of the fluke provides a mechanism for shedding of vortex rings which subsequently creates a breakwater that damps the short wavelength capillary waves. The theory also suggests that the role of natural surfactants are of secondary importance in the early formation of these prints.
Levy, R, Uminsky, D, Park, A, Calambokidis, D. A theory for the hydrodynamic origin of whale flukeprints. Int J Non-Lin Mech: Spec Iss Biol Struc. 2010;46(4): 616-626.