The Role of Metabolic Phenotype in the Capacity to Balance Competing Energetic Demands

Metabolic constraints and individual variation shape the trade‐off between physiological recovery and anti‐predator responses in adult sockeye salmon

“…Together, this suggests that physiological recovery after the chase event was prioritized over metabolic expenditure into anti‐predator activities. Recovery from a chase event is a metabolically demanding process requiring a significant portion of the animal's aerobic scope (Lawrence et al ., 2022; Priede, 1985; Redpath et al ., 2010), with scope energy being used for restoring hydromineral and energy imbalances associated with prolonged anaerobic metabolism (Wood, 1991). Consequently, metabolic rate is often elevated for a sustained period during recovery (Clark et al ., 2012; Lawrence, Eliason, et al ., 2019; Lee et al ., 2003; Scarabello et al ., 1991) with comparable responses being observed with respect to post‐recovery f H in sockeye salmon (Clark et al ., 2012; Donaldson et al ., 2010; Eliason et al ., 2013a; Prystay et al ., 2017).…”

“…In such cases, tissue oxygen demand can often exceed uptake/supply resulting in an acute reliance on anaerobic metabolism resulting in an oxygen debt (Wood, 1991), using a large proportion of the metabolic scope [i.e., excess post-exercise oxygen consumption (EPOC); Clark et al, 2012;Donaldson et al, 2011;Lee et al, 2003;Prystay et al, 2017]. Conceivably, this may have consequences for the animal responding to subsequent stressors and challenges, especially those that are metabolically demanding such as predator avoidance (Lawrence et al, 2022;Lawrence, Godin, et al, 2019;Raby et al, 2018). Our understanding of metabolic power allocation under competing metabolic demands is poor.…”

On Physiological Exhaustion in Fish Arising from Catch-and-release Angling: Mechanisms and Potential Solutions

“…The same process was followed for the second cohort of fish two weeks later, except we selected seven fish with the highest MMR and eight fish with the lowest MMR. The protocol used to determine MMR was screened for repeatability and employed the same experimental protocol outlined in Lawrence et al, 2023. Fish used in this experiment were subset from the original cohort of 70 to assess repeatability.…”

“…The only significant difference is that MMR testing protocols were employed at least 3 days in advance of our SDA trials and not immediately before the latency to feed trials as outlined in Lawrence et al (2023). MMR readings were only taken once before fish were placed in respirometers for their SDA trials.…”

“…My review identified several gaps in research, especially within the context of the applied aspects of exhaustion in recreational angling. Key directions of future research were identified as 1) understanding ecological relationship between metabolic phenotype and exercise performance, 2) characterizing measurable consequences of exhaustion related to swimming performance, 3) identify key variables that support recovery from exhaustion and 4) contextualizing these observations within the framework of ecological physiology. I explored these directions using 3 study species, barramundi (Lates calcarifer), permit (Trachinotus falcatus) and smallmouth bass (Micropterus dolomieu) using a combination of controlled experiments and field studies that employed emerging research methods and technology.…”