Here, I relate what the journalist said in his article “Pourquoi l’agriculture bio est favorable aux abeilles”. All quotes, originally in French, were translated by me.
A French study carried out in particular by Vincent Bretagnole on the “Zone-Atelier Plaine & Val de Sèvre” and published on June 26 in the Journal of Applied Ecology would be “the first to suggest and quantify the beneficial effect on Apis mellifera, agricultural systems deprived of synthetic inputs.” The difficulty was in the extent of the range of honey bees: 2 to 10 km!”
The study area covers 450 km², 10 apiaries of 5 hives each were placed in different places. The researchers observed that, when the hives had organic plots in their environment, the size of the brood (all the larvae) could “increase by up to 37%, compared to hives located at the heart of only conventional farms.” This effect was all the more noticeable as the proportion of organic plots remained limited, representing 10-30% of crops within 300 meters and 5-15% within 1,500 meters. The amount of honey “during the scarcity period” would be much higher, increasing to 53% in colonies exposed to organic.
This positive effect would be obtained even in the absence of organic rapeseed cultivation in the area. The authors “explain these positive effects by the absence of synthetic insecticides on these plots, which could prevent the destruction of forager bees“. In addition, the greater presence of weeds would benefit them.