Reproduction of the red mason solitary bee Osmia rufa (syn. Osmia bicornis) (Hymenoptera: Megachilidae) in various habitats

Abstract

Osmia rufa L. (Osmia bicornis L.) is a species of a solitary bee, which pollinates many wild and cultivated plants. A total of 900 cocoons containing mature individuals of Osmia rufa L. [450 females and 450 males of a determined (particular ?) weight], were placed in each of four habitats (orchard, mixed forest, hay meadow and arboretum of the Dendrology Institute of the Polish Academy of Sciences at Kórnik). These bees were provided with artificial nests made of the stems of common reed. The following parameters were calculated: reproduction dynamics, total number of chambers built by females, mean number of breeding chambers per reed tube and mean number of cocoons per tube. Included in the analysis were also the nectar flowers and weather conditions recorded in each of the habitats studied. General linear mixed models indicated that the highest number of chambers was recorded in the hay meadow (6.6 per tube). However, the number of cocoons per tube was similar in the hay meadow, forest and orchard (4.5-4.8 per tube) but was significantly lower in the arboretum (3.0 cocoons per tube on average). Also, the highest reproduction coefficient, 317.5%, was recorded in the hay meadows. Some nests were also parasitized and the highest mean number of infected chambers per tube (0.68) was recorded in the forest. The number of chambers was positively related to temperature. These results indicate that habitat had a significant effect on the reproduction of the red mason bee.