One of my entomological heroes is the Frenchman Jean Henri Fabre (1823-1915). He was not a great explorer, collector or taxonomist – he simply watched insects and recorded the details of their behaviour. He spent hours, sitting on the ground under the hot provencal sun, watching bees and other insects going about their daily lives. He wrote up these “stories”, some for children, but mostly for anyone to enjoy and learn from. The picture on my wall shows that he also brought the insects indoors ” en observation”. Many years ago Sally and I cycled down to Provence to visit “L’ Harmas de Jean Henri Fabre”, the house where he lived. It is now a musuem.
A few days ago, Alan sent me a short video of the mining bees visiting his “bee nest box” – you will probably have seen these for sale in garden centres and home made versions are also popular. So I watched the video and decided I would look more closely at the boxes in our garden. It seemed the appropriate thing to do given that we can’t get out and see what’s going on in the countryside. The bees have just started to hatch and leave the nests. The males emerge first and spend much of the day buzzing around the boxes waiting for females to emerge. One of the first things I discovered was that, like most bees, they need warmth and sunshine to get them flying. But they all disappeared as soon as the sun went behind a cloud. Where did they go? My nest boxes have a small viewing chamber and when I opened this I discovered that the bees had all gone back into the empty tubes for shelter. Just before dark, I had another look inside – that’s where they spend the night too!
I decided that it would be a good idea to take out many of the occupied tubes so that I could watch the bees emerge. So I placed the tubes in some plastic sweet jars that I use for rearing galls wasps etc, covered them with nylon mesh and put them on the kitchen table. The table is a little bit crowded at the moment as I do have some gall wasps emerging that I want to keep a close eye on (most are in my rearing shed). Anyway, my side of table has plenty of room but Sally is a bit squashed into a corner on her side.
The bees emerge during the day and, as long as we keep them out of the sun, they are fairly quiet. I release them next to the outside bee nests, but if I can’t get them out quick enough, the other bees are attracted in and I end up with more in the sweet jar than when I started. Pheromones are in the air! I have released two females. One I put on the box and she was immediately mounted by a male.
The other female was still on my finger when she met her mate! Perhaps I should say now that these bees Osmia bicornis are really not aggresive. On several occasions I have watched the bees with a magnifying lens, with my head virtually in the box, and a swarm of bees flying around. It’s fun and very therapeutic .
Back on the kitchen table, it is not only bees that are coming out of the tubes. There have been lots of a small beetle, apparently known as the Six spotted spider beetle because it has rather long legs (for a beetle). I have opened some tubes and the beetle (and/or its larva) are very messy feeders. Not sure what they are eating but there are certainly no bees left afterwards! And we have also seen lots of flies. I can’t work out whether they eat the bee larva (ie they are parasitoids or predators) or whether they eat the pollen placed in the tube by the adult bee for its larva to eat (ie they are kleptoparasites). Whatever they do is bad news for the bee. Outside, I have seen them waiting on the edge of a tube – are they males waiting for a female to come out or are they females waiting to sneak into the tube to lay their eggs in the nest of the bee?
In one of the tubes that I opened I found the remains (perhaps partly eaten by the beetle) of a parasitic wasp. Hoorah! This must be an internal parasitoid of the bee larva – it is a species of Monodontomerus. It has a single tooth on the (dark green) femur of the hind leg. So far, a live Monodontomerus has not emerged. Please, please, please. I want one! Still, three more weeks of lockdown yet.
None of this is really new of course but it is nice to find out for yourself. Jean Henri Fabre studied bees and wasps of several species and when we visited his “L’ Harmas” we saw the bee boxes that he had designed himself and used for his experiments. I have never found a good website for Fabre but some of his books can be downloaded. I recommend “Fabre’s Book of Insects” – My Work and My Workshop would be a good start. Fabre wrote hundreds of stories but there are thousands and thousands more to tell.
I also recommend that you don the biggest sunhat that you have (just to look the part) and sit out in the garden (if you can) and watch the insects around you.
Me – I have just decided we must go back to L’ Harmas de Jean Henri Fabre. Thanks to Sally for the photographs (except the one below -me!). Malcolm