Land use and propolis composition: an analysis of the wax content of Apis mellifera propolis

Propolis is a plant-derived resin collected by honeybees, essential for maintaining colony health by protecting against pathogens and building the hive. With the aim of determining influencing factors on the wax content of propolis, 139 samples of propolis were collected from hives across the United Kingdom in 2025 via an extensive nationwide citizen-science approach. We determined propolis mass and wax content, used a generalised linear model to analyse the relationship between colour and wax content, and principal component analysis with generalised linear mixed models to analyse the effect of surrounding land cover on propolis composition. Colour analysis indicated that colour and wax were strongly correlated. Land cover analysis indicated that hives in proximity to larger proportions of arable land and managed grasslands, with greater floral abundance, had increased wax content, compared to hives in proximity to broadleaf woodland, suburban and urban areas with more trees and less grasslands, which tended to have lowered wax content. We conclude that both the colour of raw propolis and land cover surrounding the hive strongly correlates with the wax content of propolis.