Saturday 25 July 2020

Chafers and Honeybees in France

The other day a chap on a French Beekeeping Face book group posted a photo of a beetle trying to get into one of his hives.   His initial reaction having “Googled” was that it may have been a Large hive beetle, Oplostomus fuligineus, a species that is found in Africa and although this has not yet been recorded in France we can’t be sure where anything is going to turn up these days. New non native species seem to arrive on almost a weekly basis in France and the Small hive beetle, Aethina tumida, another non native, has been found in Italy but as of this moment hasn’t reached France.

Anyway it was clearly a Chafer, that much was indisputable but not a Large hive beetle. I was sure, (ha,ha,ha), at first that it was dark Rose Chafer beetle due to its general appearance and size, (close to 2cm). However I couldn’t find any evidence of Rose Chafers trying to enter hives and although they are plentiful at our place, (Rose chafers and hives), I have never seen them on my hives so I started to deepen my search for any examples of this. After much searching and changing search terms I finally came up with some examples of where peoples hives had been invaded by chafers, but not Rose Chafers but Protaetia morio known as la Cétoine noire. In many ways they look like dark Rose chafers, they are 1.3 to 2 cm long, the dorsal surface is dull, blackish to brownish with small ochre spots more or less marked, or even absent, on the pronotum and aligned transversely on the elytra. Although the greatest populations are to be found in the Mediterranean zone they are present to some extent in almost all other regions of France. Other than the fact that they are attracted to honey their behaviour and life cycle is much the same as the Rose chafer, feeding on thistles, knapweeds etc with larval development in rotting wood and fibrous soil.  

Click on images to enlarge

It seems that the observations of them entering honey bee colonies take place in July and August and if the beetles are numerous they can cause severe disruption for the bees which can’t eject them as the beetles bodies and wing cases are too hard for a bee sting to penetrate. In the case of a hive it should be a simple case of using a hornet guard to keep them out but we can assume that they have developed this behaviour over thousands of years by entering natural colonies in trees.