Relating Turbulence and Fish Habitat: A New Approach for Management and Research

Abstract

Understanding how fish perceive turbulence characteristics to utilize complex habitats (large wood, rock, channel bedforms, etc.) is a critical, but poorly understood component of aquatic habitat restoration. Many recent studies attempt to relate turbulence characteristics to habitat utilization, but results are inconsistent for two reasons. First, turbulence is a complex, multi-scale manifestation of fluid flow that can be characterized in different ways with different interpretations. Second, fish behavioral response to flow field features is also complex because both acclimation and learning are important. For example, some studies show that turbulence decreases swimming stability, increases energy expenditure for a given swimming speed, and alters feeding behavior, whereas others show turbulence to decrease energy needed to swim at a given speed and correlates with fish abundance. We describe a Turbulence Attraction and Avoidance (TAA) hypothesis to reconcile inconsistent, even seemingly contradictory, findings. The TAA hypothesis creates a new perspective of turbulence, habitat complexity, and fish habitat occupancy by acknowledging that fish, like all animals, perceive their environment at their own relevant scales and in a conditional manner, dependent on their prior exposure history.

Habitat mapping of riverine fish by means of hydromorphological tools

“…These methods, however, have not been validated yet for riverbeds of well‐mixed grain composition, such as the one characteristic to the studied river reach. Field measurement of turbulence and mixing parameters would also contribute to the better understanding of fish behaviour as recent studies, mainly focusing on fishways, pointed out (Cotel, Webb, & Tritico, ; Liao & Cotel, ; Pavlov, Lupandin, & Skorobogatov, ; Smith, Goodwin, & Nestler, ). Although direct measurement of turbulence in large rivers is demanding, computational models with sophisticated turbulence models can be utilized instead.…”

“…These fine-scale habitat suitability maps can be applied for several purposes by riverine and conservation management. For example, dredging of the bed material and several other river regulation works may threaten the populations of large river fish (Ridenour et al, 2009;Ridenour, Doyle, & Hill, 2011 also contribute to the better understanding of fish behaviour as recent studies, mainly focusing on fishways, pointed out (Cotel, Webb, & Tritico, 2006;Liao & Cotel, 2012;Pavlov, Lupandin, & Skorobogatov, 2000;Smith, Goodwin, & Nestler, 2014). Although direct measurement of turbulence in large rivers is demanding, computational models with sophisticated turbulence models can be utilized instead.…”

A method to improve instationary force error estimates for undulatory swimmers

“…Direct measurements of instantaneous forces under turbulent flow conditions and their role on fish swimming performance require further investigation, especially when studying rheophilic families such as salmonids (Lacey et al, 2012;Smith et al, 2014).…”

Movement patterns of seaward migrating European eel (Anguilla anguilla) at a complex of riverine barriers: implications for conservation

“…This is now known not to be the case, as juvenile salmonids are capable of relatively strong swimming (e.g. Indeed, diadromous fish are likely to exhibit a complex repertoire of migratory behaviours to accommodate the diversity of physical and hydrodynamic cues they encounter as they move through freshwater and marine environments (Kemp et al 2012;Goodwin et al 2014;Smith et al 2014). Indeed, diadromous fish are likely to exhibit a complex repertoire of migratory behaviours to accommodate the diversity of physical and hydrodynamic cues they encounter as they move through freshwater and marine environments (Kemp et al 2012;Goodwin et al 2014;Smith et al 2014).…”

“…Peake & McKinley 1998), actively seek high velocity zones (Svendsen et al 2007) and avoid rapid accelerations of flow (Kemp et al 2005;Enders et al 2009;Svendsen et al 2011). Indeed, diadromous fish are likely to exhibit a complex repertoire of migratory behaviours to accommodate the diversity of physical and hydrodynamic cues they encounter as they move through freshwater and marine environments (Kemp et al 2012;Goodwin et al 2014;Smith et al 2014).…”