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Temperature is highly influential on the physiology and behaviour of ectotherms. In fish, temperature affects social interactions such as schooling behaviour, a common defence against predation. However, the effect of temperature on the ability of schooling fish to collectively respond to a predator is unknown. Here we used a loom stimulus to simulate an approaching predator that elicited a fleeing response in schooling fish over a range of water temperatures (9–29°C) and group sizes (1–16 fish). While speed and acceleration always exhibited a positive curvilinear response to temperature, the optimal temperature at which performance peaked was different during the predation threat versus when they were unperturbed. Similarly, group‐level metrics were sensitive to temperature immediately after a loom stimulus but showed no response to temperature during unperturbed swimming. The time taken for fish to respond to the loom stimulus was minimal at 20°C. The proportion of fish that startled, during a loom, peaked at 13°C – around the same temperature at which speed, and acceleration was maximum. Taken together, our results suggest that ectothermic fish may be able to compensate for their slower swim speeds at lower temperatures during unperturbed swimming by increasing their sensitivity to startle in response to a predation threat. More generally, we show that in ectotherms the qualitative and quantitative effect of temperature on a behavioural trait may be dependent on the context. [ABSTRACT FROM AUTHOR]

Background: Despite the existing knowledge about stress, trauma and pregnancy and maternal stress during natural disasters, little is known about what types of trauma pregnant or preconception women experience during these disasters. In May 2016, the worst natural disaster in modern Canadian history required the evacuation of nearly 90,000 residents of the Fort McMurray Wood Buffalo (FMWB) area of northern Alberta. Among the thousands of evacuees were an estimated 1850 women who were pregnant or soon to conceive. In August 2017, Hurricane Harvey devastated areas of the United States including Texas, with 30,000 people forced to flee their homes due to the intense flooding. Objective: To explore immediate and past traumatic experiences of pregnant or preconception women who experienced one of two natural disasters (a wildfire and a hurricane) as captured in their expressive writing. Research questions were: (1) What trauma did pregnant or preconception women experience during the fire and the hurricane? (2) What past traumatic experiences, apart from the disasters, did the women discuss in their expressive writing? Methods: A qualitative secondary analysis of expressive writing using thematic content analysis was conducted on the expressive writing of 50 pregnant or preconception women who experienced the 2016 Fort McMurray Wood Buffalo Wildfire (n = 25) and the 2017 Houston Hurricane Harvey (n = 25) Narrative data in the form of expressive writing entries from participants of two primary studies were thematically analyzed. One of the expressive writing questions was used in this analysis: "What is the most traumatic, upsetting experience of your entire life, especially that you have never discussed in great detail with others?" NVivo 12 supported thematic content analysis. Results: For some women, the disasters elicited immense fear and anxiety that surpassed previous traumatic life events. Others, however, disclosed significant past traumas that continue to impact them, including betrayal by a loved one, abuse, maternal health complications, and illness. Conclusion: We recommend a strengths-based and trauma-informed care approach in both maternal health and post-disaster relief care. [ABSTRACT FROM AUTHOR]