Animals who mate during heatwave less likely to reproduce successfully, new study shows

Animals who mate during a heatwave are less likely to reproduce successfully, according to new research led by the Universities of St Andrews and Aberdeen.

The research, published in Functional Ecology, also shows that when a heatwave occurs during mating, offspring are smaller and have lower survival rates.

As the planet continues to warm due to global climate change, the frequency and intensity of extreme weather events, such as heatwaves, is rising. Heatwaves are not just uncomfortable for humans, they also pose significant challenges for animals. Heat stress caused by these extreme events can disrupt all aspects of animal reproduction.

Understanding how animals are affected by climate change is vital, and the research looked at the potential effects of heatwaves and, in particular, the role of the timing of a heatwave event within an organism’s reproductive cycle.

Lead author Dr Natalie Pilakouta, from the University of St Andrews’ School of Biology, said: “Our research looked at burying beetles (Nicrophorus vespilloides), which are known for their exceptional parenting skills. These beetles exhibit biparental care, which is very rare in insects.

“We studied how heatwave exposure at different stages of the reproductive cycle influenced the likelihood of breeding successfully, parental care duration, offspring size, and offspring survival rate.

“We found that the timing of the heatwave really matters: when it occurs a few days before or after mating, it has little to no effect on reproductive processes. In contrast, when the heatwave occurs during mating, parents are less likely to reproduce successfully, and their offspring are smaller and have lower survival.”

The research provides novel insights and can improve the ability to make informed predictions about the ecological consequences of heatwaves under climate change.

The implications of these findings extend well beyond this specific insect species, and highlight the need to investigate these effects more broadly.

Dr Pilakouta said: “Predicting how wild populations will be affected by climate change is a challenging endeavour. This study provides another piece of the puzzle and helps us form a more complete picture of how heatwaves might shape animal reproduction and population survival.”