The Supercooling Responses of the Solitary Bee Osmia excavata (Hymenoptera: Megachilidae) under the Biological Stress of Its Brood Parasite, Sapyga coma (Hymenoptera: Sapygidae)

Abstract

(1) Background: Many insects have evolved different strategies to adapt to subzero temperatures and parasites, but the supercooling response of pollinator populations under the brood parasitism pressure has not been sufficiently investigated. (2) Methods: This study assessed the supercooling traits (supercooling points, fresh weight and fat content) of the solitary bee Osmia excavata Alfken and its brood parasite, Sapyga coma Yasumatsu & Sugihara. We measured 4035 samples (3025 O. excavata and 1010 S. coma, one individual as one sample) and discovered the supercooling traits relations between solitary bee and brood parasite. (3) Results: Significant differences in the supercooling points were found between O. excavata (females: −24.18 (−26.02~−20.07) vs. males: −23.21 (−25.15~−18.65) °C) and S. coma (females: −22.19 (−25.46~−18.38) vs. males: −20.65 (−23.85~−16.15) °C, p < 0.0001) in the same sex, and also between sexes of same species. The two species’ supercooling traits (supercooling points, fresh weight, and fat content) were significantly positively correlated. The supercooling points of the solitary bee varies regularly under brood parasitism pressure. (4) Conclusions: Our study indicates the supercooling traits relationships between a solitary bee and its brood parasite and suggests that the supercooling points of the solitary bee increase under the biological stress of its brood parasite in a certain level.

Pollinator diversity, pollination services, and conservation in agroecosystems: A mini‐review on the successes and challenges in China

“…In agricultural landscapes, Xie et al (2019) and Lu et al (2019) have investigated the foraging patterns of pollinators, noting their movements from semi‐natural habitats to croplands. Threats to pollinators, such as introduced species, natural enemies, and the application of herbicides and pesticides—particularly during flowering periods—have been documented (Mu et al, 2022; Song et al, 2021; Yan et al, 2022). Research has also extended to broader scales, like the long‐distance windborne migration of hoverflies, which are potential crop pollinators across China (Jia et al, 2022).…”

Effect of Ageing in the Mating Behaviour Sequence of Osmia cornuta Latr. (Hymenoptera: Megachilidae)

“…Insight into reproduction mechanisms and sexual recognition in O. cornuta may support the development of techniques for the rearing and management of solitary bees. Such techniques include the ease of raising O. cornuta in artificial nests [3,7,19], the optimisation of the sex ratio in rearing [25,26], the control of diapause duration [27,28], and the possibility of delaying the cocoon emergence after diapause [6,8,[29][30][31]. Only female bees perform pollen gathering; the success of courtship and mating behaviour, ensuring diploid egg production, is fundamental for the proper management of O. cornuta for pollination purposes [3][4][5]23,24].…”