Relative abilities to correct rolling disturbances of three morphologically different fish

Abstract

Responses of three fish species were measured following the addition of neutrally buoyant weight-float combinations that increased rolling instability. The three species were creek chub, Semotilus atromaculatus, largemouth bass, Micropterus salmoides, and bluegill, Lepomis macrochirus. Ability to correct posture was predicted to increase with fin size and body depth in the order creek chub < largemouth bass < bluegill. In a 90-s period, the least added torque causing fish to roll to 90° in response to disturbances, ΔT90, and the least added torque making fish unable to recover from rolling, ΔTcrit, were measured as limits of ability to correct postural disturbances. Contrary to expectations, creek chub required a 58% increase in body torque to reach ΔT90, significantly larger than the 11% increase for largemouth bass and 19% increase for bluegill. Similarly, ΔTcrit was a 78% increase in body torque for creek chub, 43% for largemouth bass, and 34% for bluegill. Increased rolling torques resulted in behaviors reducing and avoiding rolling, including tilting, which reduces metacentric height, inverted swimming, which stabilizes fish, and contacting surfaces, which generates static forces. The superior ability of creek chub to correct postural disturbances may be explained by a fin arrangement that facilitates interactions with the ground.

Streamwise vortices destabilize swimming bluegill sunfish (Lepomis macrochirus)

“…In some cases, fish can extract energy from vortices (Liao, 2007;Liao et al, 2003a;Taguchi and Liao, 2011), but in other cases, maintaining heading in unsteady flows increases energy cost (Cotel et al, 2006;Enders et al, 2003; Roche et al, 2014). Because fish respond strongly to roll perturbations (Eidietis et al, 2002), we hypothesized that streamwise vortices would destabilize swimming fish and increase the energy cost. Here, we have shown that bluegill sunfish do indeed use more energy when forced to swim in streamwise vortices.…”

“…Similarly, several groups have found increased fish abundance in areas of streams with high turbulence intensity (Smith et al, 2005;Van Zyll De Jong et al, 1997). Horizontal cylinders, in contrast, destabilize several species of fishes (Eidietis et al, 2002;Webb, 1998;Webb and Cotel, 2010). Finally, other studies have found that generalized turbulence has negative impacts on energetic demands of some fish species (Enders et al, 2003;Lupandin, 2005;Roche et al, 2014;Tritico and Cotel, 2010).…”

“…Fish have been observed to strongly avoid behaviors that lead to roll (Eidietis et al, 2002). Fish also respond more quickly to roll perturbations, compared with yaw, slip, heave and pitch disturbances (Webb, 2004).…”

Muscle activity and hydrodynamic function of pelvic fins in trout (Oncorhynchus mykiss)

“…Rotational disturbances present large control problems for swimming fish (Eidietis et al, 2002;Webb, 2002;Webb, 2004). In addition, rotational perturbations are more likely to be amplified than translational perturbations (Hoerner, 1975).…”

Response latencies to postural disturbances in three species of teleostean fishes

“…Fishes are extremely diverse. Within this diversity are various body/fin organization modes and these are believed to affect motor and stabilizing capabilities (Harris, 1937a(Harris, , 1953Moy-Thomas and Miles, 1971;Rosen, 1982;Lauder and Liem, 1983;Webb, 1998Webb, , 2004Eidietis et al, 2002;Drucker and Lauder, 2003). Studies on locomotion typically use species representative of modes, such as various dogfishes typical of less derived selachians (e.g.…”