Overcrowding of bees threatens biodiversity in Paris!

Bring the bees to town. The idea starts a few years ago thanks to urban beehives. Each large city has them, perched on the roofs of large buildings or in parks. Facilities that allow these pollinating insects to escape pesticides and stop their decline. But according to a study, too high a concentration of these apiaries would lead to harmful competition between “domestic” and wild bees. Should we throw them in the trash? Not so fast.

Biodiversity workers noticed bees have been disappearing dramatically for years. To cope, several communities have therefore encouraged the establishment of beehives. Paris in the lead. According to the last census in 2015 of the city of Paris, the capital had 687 colonies of so-called “domestic” bees, for as many apiaries. And since then, their number has continued to increase. In 2017, the capital even adopted a “Beehives and pollinators” plan, aimed at continuing to install apiaries by 2020.

Bee pollinating a flower in Le jardin des Plantes, Paris, France © Jacques Julien
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Competition between pollinators

For three years, several researchers observed the operation of some of these hives in the capital. According to their results the density of apiaries is not without consequence. Because once the flowers have been collected by the “domestic” bees, there would be nothing left for the wild ones.

“It has been observed that where domestic hives are installed, there are fewer passages of wild pollinators, such as bumblebees, butterflies, small and large wild bees on flowers,” analyzes Isabelle Dajoz, professor and researcher in ecology and co-author of the study. If the “domestic” bees, of their real name “Apis mellifera”, – honey bees – are the best known, there are in fact 1,000 species of bees in France. Wild, solitary bees, unlike their counterparts, are not raised in hives and are solitary.

In areas of strong competition, we must therefore organize ourselves. We need to place more plants. We can plant more honey plants such as lavender, rosemary, or even lime, concludes a beekeeper.

Asian hornet, a serious threat to the beekeeping sector and harms biodiversity

The Asian hornet (Vespa velutina nigrithorax) causes significant damage in orchards by devouring fruit and it has the particularity of attacking bees. Forager bees constituting 80% of the diet of an Asian hornet in town and 45% in the countryside. Although not all bees die, they are highly stressed by Asian hornets predation , which limits nectar and pollen harvests and lowers their winter stores.

It appeared in the south of Ile-de-France in 2014. From 50 nests listed in 2015, we went to 269 in 2016 and 391 in 2017 over the whole region. And this is only the tip of the iceberg. A nest of an Asian yellow-legged hornet was discovered on July 13, 2016 in the premises of the National Museum of Natural History in Paris. Asian hornets are gaining ground in the capital.

More of my bees photos here