Relative Cost/Benefit Trade‐Off Between Cover‐Seeking and Escape Behaviour in an Ancestral Fish: The Importance of Structural Habitat Heterogeneity

Abstract

Fleeing from predators and moving into protective habitats are two common antipredator behaviours in the animal kingdom. Surprisingly, the relative cost/benefit trade‐off of each behavioural option has rarely been examined empirically. Here, we investigate the interplay between decisions surrounding escape behaviour and rocky microhabitat occupancy in lake sturgeon, Acipenser fulvescens. In high‐risk clear‐water environments, sturgeon responded to danger by evoking an escape response and by seeking cover in rocky microhabitats. However, in low‐risk turbid environments, we found that sturgeon responded to danger by seeking cover in rocky microhabitats, but not fleeing to a significant degree. Cover‐seeking behaviour may therefore be a relatively low‐cost/high‐benefit antipredator strategy. These findings highlight the importance of structural habitat heterogeneity for prey animals in predator‐dominated landscapes.

Vegetation and predator interactions affect northern bobwhite behavior

“…This result indicates bobwhites are capable of threat‐type detection and threat‐sensitive predator avoidance responses (Helfman ). Evidence for threat‐sensitive behavior has been reported in other taxa such as fish (Brown and Dreier , Wishingrad et al ), passerines (Turney and Godin , Freeberg et al ), and ungulates (Creel et al , Kuijper et al ).…”

“…Anti‐predator behavior remains a complex and poorly understood topic because numerous factors such as vegetation structure (Wishingrad et al ), food availability (Lima and Dill , Stears and Shrader ), and associative learning affect prey and predator during an encounter. Prior exposure to predators (Mateo , Martin et al , Gregory ) and behavioral cues learned during interactions with predators (Stankowich and Blumstein , Cooper , Freeberg et al ) further obfuscate our understanding because future behavior can be governed by past experiences.…”

Body condition, rather than size, predicts risk‐taking and resource holding potential in hatchery reared juvenile lake sturgeon Acipenser fulvescens

“…, Wishingrad et al . () placed three A. fulvescens (mean ± SD L T = 67.0 ± 6.7 mm) together in an arena (360.0cm 2 fish −1 ), whereas in our study six A. fulvescens (mean ± SD L T = 78.0 ± 6.1 mm) were held in an arena (426.9 cm 2 fish −1 ) to provide more appropriate ecological context given the gregarious nature of the species at this age class (Barth et al ., ). Indeed, spottail shiner Notropis hudsonius (Clinton 1824) tolerate closer predator approach when in groups (Seghers, ) and from a meta‐analysis perspective of fish risk assessment, increasing groups size was found to diminish perceived predation risk (Stankowich & Blumstein, ).…”

Risk in a changing world: environmental cues drive anti-predator behaviour in lake sturgeon (Acipenser fulvescens) in the absence of predators

“…However, turbidity has also been found to reduce predation risk for northern pike (Esox lucius) (Lehtiniemi et al, 2005), white sturgeon (Acipenser fulvescens) (Gadomski & Parsley, 2005) and damselflies (Ischnura elegans) (Van de Meutter et al, 2005), allow fathead minnows to use feeding grounds occupied by a predator (Abrahams & Kattenfeld, 1997;Chiu & Abrahams, 2010), and allow lake sturgeon (Acipenser fulvescens) to curtail costly escape behaviours (Wishingrad et al, 2014a). Furthermore, Ferrari et al (2014) found that delta smelt (Hypomesus transpacificus) that evolved in turbid-water environments are decimated by predators in clear-water environments as they rely exclusively on turbidity to avoid predators.…”