marine biology Marine biology is the scientific study of the biology of marine life, organisms in the sea. Given that in biology many phyla, families and genera have some species that live in the sea and others that live on land, marine biology classifies s ...

, a flukeprint is a patch of calm water on the surface of the ocean, formed by the passing of a

whale Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and ...

. Flukeprints may also be named by the word for them in the Inupiaq language, qala. As with other forms of

animal track __notoc__ An animal track is an imprint left behind in soil, snow, or mud, or on some other ground surface, by an animal walking across it. Animal tracks are used by hunters in tracking their prey and by naturalists to identify animals living ...

s, flukeprints may be used in

hunting Hunting is the human activity, human practice of seeking, pursuing, capturing, or killing wildlife or feral animals. The most common reasons for humans to hunt are to harvest food (i.e. meat) and useful animal products (fur/hide (skin), hide, ...

, to follow whales that are invisible beneath the ocean surface, and to determine the size of an unseen whale. They have also been used for similar purposes by scientists studying whales.

Fluid dynamics In physics and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids— liquids and gases. It has several subdisciplines, including ''aerodynamics'' (the study of air and other gases in motion) an ...

researchers have proposed multiple mechanisms for the formation of flukeprints, including

vortex shedding In fluid dynamics, vortex shedding is an oscillating flow that takes place when a fluid such as air or water flows past a bluff (as opposed to streamlined) body at certain velocities, depending on the size and shape of the body. In this flow, v ...

from the fluke of the whale, the action of

surfactant Surfactants are chemical compounds that decrease the surface tension between two liquids, between a gas and a liquid, or interfacial tension between a liquid and a solid. Surfactants may act as detergents, wetting agents, emulsifiers, foaming ...

s on the surface of the water, and

shear flow The term shear flow is used in solid mechanics as well as in fluid dynamics. The expression ''shear flow'' is used to indicate: * a shear stress over a distance in a thin-walled structure (in solid mechanics);Higdon, Ohlsen, Stiles and Weese (1960) ...

in the interaction between

water wave In fluid dynamics, a wind wave, water wave, or wind-generated water wave, is a surface wave that occurs on the free surface of bodies of water as a result from the wind blowing over the water surface. The contact distance in the direction of t ...

s and the current caused by the passing whale.

References

{{reflist, refs= {{citation , last1 = Hanson , first1 = MB , last2 = Baird , first2 = RW , last3 = Ford , first3 = JKB , last4 = Hempelmann-Halos , first4 = J , last5 = Doornik , first5 = DM Van , last6 = Candy , first6 = JR , last7 = Emmons , first7 = CK , last8 = Schorr , first8 = GS , last9 = Gisborne , first9 = B , last10 = Ayres , first10 = KL , last11 = Wasser , first11 = SK , last12 = Balcomb , first12 = KC , last13 = Balcomb-Bartok , first13 = K , last14 = Sneva , first14 = JG , last15 = Ford , first15 = MJ , date = March 2010 , doi = 10.3354/esr00263 , journal = Endangered Species Research , pages = 69–82 , publisher = Inter-Research Science Center , title = Species and stock identification of prey consumed by endangered southern resident killer whales in their summer range , volume = 11, doi-access = free {{citation , last = Jeffries , first = Glen , date = April 25, 2017 , magazine = Hakai magazine , title = The Path of the Unseen Whale , url = https://www.hakaimagazine.com/article-short/path-unseen-whale/ {{citation , last1 = Levy , first1 = R. , author1-link = Rachel Levy (mathematician) , last2 = Uminsky , first2 = D. , last3 = Park , first3 = A. , last4 = Calambokidis , first4 = J. , date = May 2011 , doi = 10.1016/j.ijnonlinmec.2010.12.009 , issue = 4 , journal = International Journal of Non-Linear Mechanics , pages = 616–626 , title = A theory for the hydrodynamic origin of whale flukeprints , volume = 46 {{citation , last1 = Rousseaux , first1 = Germain , last2 = Uminsky , first2 = David , last3 = Levy , first3 = Rachel , author3-link = Rachel Levy (mathematician) , contribution = Flukeprints of cetaceans and the corresponding shear flow phenomenon , citeseerx = 10.1.1.710.938 , date = August 2013 , pages = P11:1–P11:6 , title = Eighth International Symposium on Turbulence and Shear Flow Phenomena Whales