Abstract. Many of the world’s marine fish stocks are either fully or partially overfished and require management. Next to fisheries, the annual recruitment of young-of-the-year to adult spawning stocks determines the dynamics of marine fish populations. Precise estimates of the annual variability in recruitment are crucial for management, e.g. the definition of sustainable catch quota. To better predict recruitment, field-based monitoring of the particularly vulnerable early life stages of fish, collection of information on abiotic and biotic field conditions, and laboratory experiments that simulate relevant conditions are commonly used to estimate year-class success. Laboratory experiments support a holistic picture of how different levels of environmental and anthropogenic stressors affect larval fish survival, growth, condition, and various performance traits. Moreover, results from controlled laboratory studies can provide optimum and threshold levels for important traits under specific conditions, and the physiological information can be used to parameterize individual-based models that predict larval fish foraging, growth and survival. I will discuss how physiological measurements can help us gain a mechanistic understanding of how changes in abiotic and biotic conditions modify energetic requirements and how their effects scale up from cellular to whole organism and population levels. By providing examples from temperate regions, I will show how powerful combining physiological data from laboratory observations with environmental data can be to predict bottlenecks for larval fish survival under current and future ocean conditions. I will conclude by discussing how these approaches can benefit research on coral reef fish offspring.
Biography. Björn is originally from Germany where he completed his doctoral studies at the University of Hamburg (2016), investigating how abiotic and biotic factors determine important characteristics of the early life stages of the Atlantic herring. Moving from temperate to tropical waters, Björn visited A/Prof. Jodie Rummer’s group at the Centre of Excellence in 2016 and joined her lab again in 2017, funded by scholarships from the German Academic Exchange Service (DAAD) and the German Research Foundation (DFG). At the Centre of Excellence, Björn’s research integrates physiological and behavioural observations of coral reef fish larvae to investigate how coral reef fish offspring will cope with more extreme conditions under projected climate change conditions.