Metabolic fright responses of different-sized largemouth bass (Micropterus salmoides) to two avian predators show variations in nonlethal energetic costs

Abstract

Recently, researchers have identified that nonlethal costs of predation may arise not only from lost energy intake but also potentially from increased energetic expenditure. During periods of heightened stress following unsuccessful predation attempts, organisms may remain in an altered physiological state with elevated metabolism for some time. Few studies have quantified these nonlethal energetic costs of predation. We monitored the cardiac response (cardiac output (Q), heart rate (f H ), and stroke volume (SV H )) of largemouth bass, Micropterus salmoides, ranging in size from 200 to 425 mm, to simulated avian predation attempts by great blue heron, Ardea herodias, and osprey, Pandion haliaetus. Fear bradycardia during a 30-s predation attempt varied depending upon the size of the fish and the type of predator. The magnitude of the bradycardia decreased with increasing size of the fish; however, the disturbances were more extreme in response to osprey than to blue heron models. Maximal cardiac disturbance following simulated predation attempts by osprey were consistent among size classes of bass. However, the magnitude of the disturbance following heron predation attempts reduced as the size of the fish increased. Size-specific trends were even more extreme for cardiac-recovery durations. Largemouth bass of all sizes exposed to osprey predation attempts required -40 min for Q and f H and -30 min for SV H to return to predisturbance levels. Although small bass exposed to heron predation attempts required recovery times similar to fish exposed to osprey predation attempts, as the size of largemouth bass exposed to the heron model increased above -300 mm, the recovery time decreased significantly. We conclude that the size-specific response of largemouth bass to different predators is reflective of their ability to assess the risk posed by different predators. In addition, the nonlethal costs of predation can be substantial and should be considered in future bioenergetics models. 709Résumé : Récemment, des chercheurs ont découvert que les coûts non létaux de la prédation peuvent être reliés non seulement à la baisse de l'apport d'énergie, mais aussi à l'augmentation de la dépense énergétique. Durant les périodes de stress important qui suivent des essais infructueux de prédation, les organismes demeurent dans un état physiologique perturbé avec un métabolisme élevé pendant un certain temps. Peu de chercheurs se sont attardés à quantifier ces coûts énergétiques non létaux de la prédation. Nous avons mesuré la réaction cardiaque (rendement (Q), rythme (ƒ H ) et volume systolique (SV H )) chez des achigans à grande bouche (Micropterus salmoides) de 200 à 425 mm à des attaques simulées de prédation par le grand héron bleu, Ardea herodias, et par le balbuzard pêcheur, Pandion haliaetus. La bradycardie causée par la peur reliée à une tentative de prédation de 30 s variait en fonction de la taille du poisson et du type de prédateur. L'amplitude de la bradycardie diminuait en fonction inverse de la taille du poisson et l...

The effects of noise disturbance from various recreational boating activities common to inland waters on the cardiac physiology of a freshwater fish, the largemouth bass (Micropterus salmoides)

“…For example, when largemouth bass were exercised to exhaustion and brief air exposure, heart rate increased by 78 to 108% (Cooke et al, 2003a) and by 95% following a tournament weigh-in (Suski et al, 2004). Similar disturbances to those observed for the canoe treatment have previously been noted for a bass following a small movement (10 s displacement, 28%; Cooke et al, 2002) or when large bass are exposed to a simulated heron attack (20%; Cooke et al, 2003b). The magnitude of heart rate disturbance for the trolling motor treatment compares with simulated predator attacks on bass by osprey models (44%; Cooke et al, 2003b).…”

Avian predators transmit fear along the air–water interface influencing prey and their parental care

“…predatory bird is circling overhead (indeed, the fish shape is strongly contrasted against the excavated nests). By exposing largemouth bass (Micropterus salmoides (Lacepède, 1802)) to a similar Osprey model under controlled laboratory settings, Cooke et al (2003) induced bouts of cardiac disturbance (i.e., bradycardia) in experimental fish, thus suggesting that the nonlethal costs of avian predation have profound implications for altering physiological state and elevating metabolism in centrarchids. Our results from the exposure portion of our experiment add behavioral perspectives to the findings from Cooke et al (2003) that suggest avian predation risk is acute and profound for fish with direct consequences for present and future fitness.…”

Factors Affecting Catch‐and‐Release Mortality of Bluefish

“…BLUEFISH CATCH-AND-RELEASE MORTALITY and Parker 2004) and enable quicker recovery from stress-related disturbance (Cooke et al 2003). In addition, the scaling of standard weight-specific metabolic rate with size (Brett and Groves 1979) should provide larger fishes with increased metabolic scope to avoid exceeding metabolic limits during periods of high stress (Priede 1985).…”