Queens, but not their stored sperm, are resilient to temperature stress

Abstract

Abiotic stressors such as extreme temperatures can reduce stored sperm viability within queen honey bees. However, little is known about how thermal stress may directly impact queen performance or other maternal quality metrics, such as queen mass, egg laying rate, and development of embryos within eggs. Here, in a blind field trial, we recorded laying pattern, queen mass, and average callow worker mass before and after exposing queens to a cold temperature (4°C, 2 h), hot temperature (42°C, 2 h), and hive temperature (33°C) to serve as a handling control. We then used proteomics to investigate potential vertical effects of maternal temperature stress on embryos, as well as to measure the abundance of previously determined protein markers for temperature stress in the spermathecal fluid. We found no significant effect of abiotic stress on any of the metrics we recorded. These data suggest that there are likely no lasting maternal effects of temperature stress on honey bee queens, and that the queens themselves are highly stress tolerant, but not their stored sperm.