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Climate‐driven species redistribution is pervasive and accelerating, yet the complex mechanisms at play remain poorly understood. The implications of large‐scale species redistribution for natural systems and human societies have resulted in a large number of studies exploring the effects on individual species and ecological communities worldwide. Whilst many studies have investigated discrete components of species redistribution, the integration required for a more complete mechanistic understanding is lacking. In this paper, we provide a framework for synthesising approaches to more robustly understand and predict marine species redistributions. We conceptualise the stages and processes involved in climate‐driven species redistribution at increasing levels of biological organisation, and synthesize the laboratory, field and modelling approaches used to study redistribution related processes at individual, population and community levels. We then summarise links between scales of biological organisation and methodological approaches in a hierarchical framework that represents an integrated mechanistic assessment of climate‐driven species redistributions. In a rapidly expanding field of research, this framework provides direction for: 1) guiding future research, 2) highlighting key knowledge gaps, 3) fostering data exchange and collaboration between disciplines and 4) improving shared capacity to predict and therefore, inform the proactive management of climate impacts on natural systems.

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Barred sand bass Paralabrax nebulifer (Family: Serranidae; BSB) are among the most popular recreational game fishes in southern California and an important food fish. Patterns of residency and habitat use are critical for determining the potential for BSB to be impacted by point source anthropogenic contaminants prevalent in the densely populated coastal environment near Los Angeles, California. Home ranging behavior, degree of site fidelity, residency, habitat selection, and seasonal spawning migration of BSB were observed over 27 mo using a large, continuous coverage, fine-scale acoustic telemetry array (~20 km 2 ). The 55 tagged individuals used small core areas (mean ± SD = 2682 ± 2005 m 2 over 329 ± 227 d) and showed high affinity for the rock/sand ecotone at a depth of 20 to 30 m. Overall weekly residency to the array was 70 ± 25% of tagged fish present from the first tag date through the end of the study, with lower residency during the summer spawning season (June to August). Individuals leaving the array emigrated in a southeasterly direction 98% of the time, and 100% of the BSB detections outside the array occurred to the southeast of the Palos Verdes Shelf Superfund Site (PVSSS; 26.4 ± 0.8 km). BSB of legal size (> 360 mm TL) exhibit high long-term site fidelity to small areas within the PVSSS and make seasonal migrations to spawning aggregations beyond the boundaries of the 'do not consume' zone defined by the Office of Environmental Health Hazard Assessment in 2009.

Extensions of species’ geographical distributions, or range extensions, are among the primary ecological responses to climate change in the oceans. Considerable variation across the rates at which species’ ranges change with temperature hinders our ability to forecast range extensions based on climate data alone. To better manage the consequences of ongoing and future range extensions for global marine biodiversity, more information is needed on the biological mechanisms that link temperatures to range limits. This is especially important at understudied, low relative temperatures relevant to poleward range extensions, which appear to outpace warm range edge contractions four times over. Here, we capitalized on the ongoing range extension of a teleost predator, the Australasian snapper Chrysophrys auratus, to examine multiple measures of ecologically relevant physiological performance at the population’s poleward range extension front. Swim tunnel respirometry was used to determine how mid-range and poleward range edge winter acclimation temperatures affect metabolic rate, aerobic scope, swimming performance and efficiency and recovery from exercise. Relative to ‘optimal’ mid-range temperature acclimation, subsequent range edge minimum temperature acclimation resulted in absolute aerobic scope decreasing while factorial aerobic scope increased; efficiency of swimming increased while maximum sustainable swimming speed decreased; and recovery from exercise required a longer duration despite lower oxygen payback. Cold-acclimated swimming faster than 0.9 body lengths sec−1 required a greater proportion of aerobic scope despite decreased cost of transport. Reduced aerobic scope did not account for declines in recovery and lower maximum sustainable swimming speed. These results suggest that while performances decline at range edge minimum temperatures, cold-acclimated snapper are optimized for energy savings and range edge limitation may arise from suboptimal temperature exposure throughout the year rather than acute minimum temperature exposure. We propose incorporating performance data with in situ behaviour and environmental data in bioenergetic models to better understand how thermal tolerance determines range limits.