The Hornet Hoverfly and the Hornets

In August we reported about the hornet hoverfly (Volucella zonaria) and its interesting life history (see here for the blog entry: http://www.urbanpollinators.blogspot.co.uk/2012/08/meet-hornet-hoverfly-volucella-zonaria.html).

In short, the female hornet hoverfly  will seek out a wasp or hornet nest to lay its eggs in the nest. The hoverfly larvae develop in the nest and eat the detritus (dead or dying hornets and larvae). Today we witnessed the hornet hoverfly behaviour of seeking out a hornet nest to lay its eggs first-hand on an allotment site in Reading.

On the allotment site an allotment plot holder told us about a bee nest near his allotment plot. When we had a look it turned out to be a hornet nest with hornets buzzing in and out of the entrance to the nest in an old compost heap.We watched the hornets flying in and out for a while before we discovered a female hornet hoverfly (easy to recognize as it has the eyes separated with a wide yellow band) sitting on a nettle leave near the entrance.

After sitting there for a while the hornet hoverfly started to creep closer ...

... and closer ...

... until it was right near the entrance of the hornet nest with the hornets flying past it in and out of the nest (you can see the hornet hoverfly sitting on the left in the picture above, a hornet flying to the nest entrance on the right). The hornet hoverfly sat there for a while, watching the hornets flying past, then it started to fly towards the nest entrance, sneaking past the angry looking hornets at the entrance (see picture below) and disappeared in the hornet nest. The hornets seemed not to notice the hoverfly at all and just continued flying in and out.

We found it amazing to watch this hornet hoverfly behaviour first-hand after we read about it in a book and on the internet. Allotment sites are always good for a surprise.