Red mason bee (Osmia bicornis) thermal preferences for nest sites and their effects on offspring survival

Abstract

Ectotherms usually require a narrow range of thermal conditions for development; thus, parental selection of oviposition sites is crucial. In a field experiment, we investigated female solitary red mason bee (Osmia bicornis) preferences for potential nest site temperatures and their effects on offspring development. The results showed that bees detected and avoided nest sites with high temperatures (28°C) and often chose cooler (24°C) or ambient temperatures (average 18–20°C). This is a protective behaviour because offspring survival decreases with increasing nest temperature, mostly due to mortality at the egg stage. Elevated temperatures also led to weight loss in adult bees. However, hot nest temperatures appeared to deter adults or kill parasite larvae, as the highest numbers of parasites were observed in unheated nests. We concluded that choosing the proper temperature for nests is an important element in bee life strategies, especially in warming environments.

Habitat amount, temperature and biotic interactions drive community structure, life-history traits, and performance traits of cavity-nesting bees and wasps and their natural enemies in cities

“…from late summer to the following spring. Temperature sensitivity can vary during ontogeny (Rombough, 2003), and thermal conditions during the larval and pupal stages can therefore be critical for later CNBW development and emergence (Rombough, 2003; Ostap-Chec et al, 2021). Hence, future studies should extend temperature measurements to also include the all developmental stages of CNBW.…”

Bees exposed to climate change are more sensitive to pesticides

“…Temperature increases such as those simulated in our study are likely to have a stronger impact in populations from already warm environments, living closer to the thermal safety limits of the species, than in northern populations (CaraDonna et al, 2018). Bees may also mitigate the effects of climate warming by actively selecting cooler nesting sites, as shown in O. bicornis (Ostap‐Chec et al, 2021), or through latitudinal or altitudinal migration to cooler areas (Kerr et al, 2015). At any rate, the fact that temperature increases similar to those of our most pessimistic scenario have been recorded in recent years (AEMET, 2021; Copernicus, 2020) suggests that the combined effects of climate warming and pesticide exposure are already affecting bee population dynamics.…”

Pre- and post-oviposition behavioural strategies to protect eggs against extreme winter cold in an insect with maternal care

“…While temperature often drives oviposition site selection to ensure that the lack of egg mobility does not result in exposure to sub-optimal or extreme temperatures (Pike et al 2012;Li et al 2018;Ostap-Chec et al 2021), the role of temperature on oviposition site selection is less clear when mothers can transport the eggs after oviposition. Here, we show in the European earwig that this capability does not prevent females from selecting oviposition sites according to temperature and that egg transport can indeed help mothers to adjust egg temperature after oviposition.…”

“…These effects can be particularly strong in eggs because they are immobile and thus unable to escape from environmental temperatures, their shell often provides limited thermal protection, and the development and survival of embryos (contained in eggs) are generally sensitive to subtle changes in surrounding temperatures (Wang et al 2010;Nicolai et al 2013;Mortola and Gaonac'h-Lovejoy 2016;Cordero et al 2018;Yang et al 2018). As a result, females of many species select oviposition sites according to optimal temperatures for their eggs, such as in the toad-headed agama lizard Phrynocephalus przewalskii Strauch, 1876 (Li et al 2018), the solitary red mason bee Osmia bicornis (Linnaeus, 1758) (Ostap-Chec et al 2021), or the flat-rock spiders Hemicloea major (Koch, 1875) (Pike et al 2012).…”