A team of French researchers, some of them from the French National Institute for Agricultural Research, has just shown for the first time that organic agriculture benefits honey bee colonies feeding particularly during the period of food scarcity at the end of spring. The research team analyzed six years of data collected as part of a unique monitoring tool of domestic bees. This study appeared in the June 26 edition of the Journal of Applied Ecology.
Bees are not only useful to humans as producers of honey, but also as pollinators of wild flowers and crops. They feed exclusively on the nectar and pollen and thus suffer from the low availability of flower in May in June between the flowering periods of rapeseed and sunflowers, which is typical of very intensive agricultural landscapes. During this period, the rate of pollen collection, honey production and colony growth decreases. The study showed that organic agriculture can limit this decline. Parcels of land grown using organic agricultural practices offered domestic bees more resources, particularly through the presence of non-crop plants (which are often incorrectly called “weeds”). Researchers found an increase of up to 37% in the brood, 20% more adults, and 53% more extra honey in the colonies surrounded by lands using organic agriculture than colonies in conventional agricultural environments in a study of 180 hives over six years in central western France.
This suggest that the presence of organic agricultural parcels can lead to different effects. The increase in brood production destined to become workers can be due to greater level of diversity of pollen resources and a decrease in bee mortality due to pesticides at the local level. Honey reserves can increase due to the larger availability of flowers on a greater spatial scale, which corresponds to the size that bees habitually look for resources (between 1 and 3 kilometers in field crop areas).
This study was made possible thanks to a unique bee colony monitoring scheme called Ecobee. It always to annually measure the effects of agricultural practices in real condition on 50 experimental beehives in the southwest of France. Further study lead by the same team showed that the decrease in production of worker broods during the flowering period was rare, leading to a decrease in the survival of colonies in winter. This new study suggests that organic agriculture can limit the negative effects of intensive agriculture and increase the chances of survival of these essential pollinators.