Mechanics of Remora Removal by Dolphin Spinning

Remora attachment is enhanced by spinule friction

“…It has been suggested that attaching to mobile hosts benefits the remoras by reducing metabolic demands for swimming (Muir and Buckley, 1967), offering opportunistic feeding (Strasburg, 1962) or increasing the chance of finding mates (Silva and Sazima, 2003). Remoras have been known to strongly attach to sharks (Ritter, 2002;Ritter and Brunnschweiler, 2003), rays (Williams et al, 2003), other pelagic fish (Williams et al, 2003), sea turtles (Sazima and Grossman, 2006), dolphins (Weihs et al, 2007), divers (Silva and Sazima, 2003), buoys (Cressey and Lachner, 1970), ship hulls (Cressey and Lachner, 1970) and concrete (Strasburg, 1962). This variety of hosts moves at many different speeds and have body surfaces that span a broad spectrum of geometries and topologies (Stote et al, 2014).…”

Theoretical and computational fluid dynamics of an attached remora ( Echeneis naucrates )

“…Although remoras are not considered parasites in the sense that they feed off their host, they are certainly parasites in the sense that extra swimming effort must be supplied by the host to compensate for the hitchhiking remora (Fertl and Landry, 2002;Fish et al, 2006;Weihs et al, 2007;Silva and Sazima, 2008). To estimate the increased rate of energy expenditure by the host, the parasitic drag power was computed as the product of the drag force and the host swimming speed (equivalent to the free-stream velocity with respect to the remora).…”

“…1A and B) in the Echeneidae family have adapted a unique dorsal suction pad that allows them to attach to various host organisms and marine vessels. The list of hosts includes, but is not limited to, sharks, whales, rays, other pelagic fish, sea turtles, dolphins, divers, buoys, ship hulls, and concrete (Strasburg, 1962;Cressey and Lachner, 1970;O'Toole, 2002;Ritter, 2002;Ritter and Brunnschweiler, 2003;Silva and Sazima, 2003;Williams et al, 2003;Sazima and Grossman, 2006;Weihs et al, 2007). Proposed benefits to remoras include transportation ("hitchhiking"), protection from predators, increased courtship/reproduction potential, enhanced gill ventilation and expanded feeding opportunities (Fertl and Landry, 1999).…”

“…With respect to the benefits of the host organism, certain remora species have been known to feed on parasites attached to the host (Strasburg, 1959;Cressey and Lachner, 1970); however, there are many documented cases of hosts that are either unwilling to serve (Aughtry, 1953;Strasburg, 1962) or attempt to remove remoras by various means (Ritter, 2002;Ritter and Brunnschweiler, 2003;Fish et al, 2006;Weihs et al, 2007)). Despite work that has been done to better understand the attachment strength (Fulcher and Motta, 2006) and physical mechanisms associated with remora attachment (Nadler et al, 2013;, very little has been done to quantify the primary force that remoras must overcome in order to maintain attachment, namely fluid drag.…”

Hydrodynamic properties of fin whale flippers predict maximum rolling performance

“…Rolls form the basis for more complex maneuvers, such as banked turns (Schilstra and Hateren, 1999), and are used as building blocks for intricate maneuvering trajectories. Rolling performance affects many functions including reorientation of the visual field (Goldbogen et al, 2013), prey capture and feeding (Fish, 2002;Fish et al, 2007), cleaning (Limbaugh, 1961), social interactions (McBride and Kritzler, 1951) and dislodging parasites Weihs et al, 2007). Baleen whales in the family Balaenopteridae, or rorquals, frequently roll during feeding events (Goldbogen et al, 2006;Kot and Borda, 2014).…”