LAUSR

Temperature is critical in regulating virtually all biological functions in fish. Low temperature stress (cold shock/stress) is an often-overlooked challenge that many fish face as a result of both natural events and anthropogenic activities. Here we present an updated review of the cold shock literature based on a comprehensive literature search, following an initial review on the subject (i.e., Donaldson et al., 2008 J. Fish Biol. 73: 1491). We focus on how knowledge on cold shock and fish has evolved over the last decade, describing advances in our understanding of the generalised stress response in fish under cold stress, what metrics may be used to quantify cold stress, and what knowledge gaps remain to be addressed in future research. We also describe the relevance of cold shock as it pertains to environmental managers, policymakers, and industry professionals, including practical applications of cold shock. While substantial progress has been made in addressing some of the knowledge gaps identified a decade ago, other topics (e.g., population-level effects, interactions between primary, secondary, and tertiary stress responses) have received little or no attention despite their significance to fish biology and thermal stress. Approaches using combinations of primary, secondary, and tertiary stress responses are crucial as a research priority in order to better understand the mechanisms underlying cold shock responses, from short-term physiological changes to individual- and population-level effects, thereby providing researchers with better means of quantifying cold shock in laboratory and field settings.