DOI: 10.5061/dryad.4mw6m90r7
title: Macronutrient composition in pollen affects development and survival in wild bees

description: Pollinators rely on diverse floral resources to meet their nutritional
 needs, as pollen macronutrient composition varies significantly among
 plant species, influencing bee development and survival. In this study, we
 collected freshly laid eggs of the small carpenter bee (Ceratina
 calcarata) from artificial nest substrates and reared them on diets
 formulated with black poplar (Populus nigra) and dandelion (Taraxacum
 officinale) pollen, while closely monitoring developmental metrics, lipid
 content, and survival. We also conducted macronutrient analyses on both
 pollen types to quantify protein, amino acids, fatty acids, and sugars.
 While dandelion pollen is abundant and carbohydrate-rich, it contained
 lower levels of protein, essential amino acids, and several fatty acids in
 our analyses, a nutrient profile that corresponded with slower larval
 development in our study. In contrast, black poplar pollen despite being
 primarily wind-dispersed had higher concentrations of protein, essential
 amino acids, and fatty acids in our analyses and supported better
 developmental performance. Bees reared on black poplar pollen exhibited
 faster maturation, larger head widths, and greater body mass, highlighting
 the possible role of protein availability in development. Survival
 analysis further revealed that protein-rich diets supported higher brood
 viability, whereas bees fed dandelion pollen experienced delayed
 development and reduced body sizes. Bees on 50:50 mixed diets displayed
 intermediate development times and improved survival, highlighting the
 benefits of dietary diversity in mitigating nutritional stress. These
 findings emphasize the importance of arboreal pollen as a possible
 nutritional resource and the potential to incorporate tree pollen sources
 into conservation planning. Given the increasing pressures of habitat loss
 and climate change, ensuring access to nutritionally diverse pollen
 sources may be useful for sustaining pollinator populations and promoting
 ecosystem resilience.
description: # Macronutrient composition in pollen affects development and survival in
 wild bees Dataset DOI:
 [10.5061/dryad.4mw6m90r7](https://doi.org/10.5061/dryad.4mw6m90r7) ##
 Description of the data and file structure Nutritional manipulation of
 wild bees fed on pollen balls made of different ratios of poplar and
 dandelion in comparison to control field collected pollen balls with no
 nutritional modification. Eggs were placed on control or experimental
 pollen balls and developmental rates and survival to adulthood recorded as
 well as body size and lipid stores in those individuals that survived to
 adulthood across treatments. ### Files and variables #### File:
 Supplementary_Tables_Phys_Ent_July_29.xlsx **Description:**  **Table S1.
 Head width measurements**. Head width (mm) of adult bees across different
 treatments. Measurements are taken at the widest part of the head capsule
 post-eclosion. **Table S2. Development time**. Total days from egg to
 adult emergence for individual bees under different treatments.
 Development duration reflects treatment impact on life cycle progression.
 **Table S3. Body mass**. Final dry mass (mg) of adult bees following
 treatment conditions. Values inform analysis of nutritional and
 environmental effects on growth outcomes. **Table S4. Lipid values.**
 Total lipid content (μg) measured per individual bee across treatments.
 Lipid data were derived from chemical extraction and quantification
 methods.