Twenty bees and counting

I've written on a few occasions about insect-friendly gardening and farming, and sometimes focused on a single species that has been attracted such as my recent observation of an unusual specimen of the wool-carder bee. I'd noticed that the combination of pollinator-friendly planting and the provision of habitat features such as bee-logs, so having seen a few more species yesterday during a welcome sunny patch, I decided to look through my list of garden species records for 2012 so far. I knew there was fairly good bee diversity in our garden, but was pleasantly surprised to find that I have already identified 20 species this year, with some others remaining unidentified so far. So, though the English drizzle has returned today, I thought I'd celebrate by sharing a few of these species...

First of all, a quick look at one of the species that has definitely made good use of the insect hotel I built in time for spring this year, the red mason bee Osmia rufa.

Bee-log with pre-drilled tunnels filled by Osmia rufa cells and sealed with mud.

Osmia rufa exiting a tunnel in the bee-log.

O. rufa is well-known to bee-friendly gardeners as it often entirely takes over artificial bee nest-boxes in the same way as it has used the bee-log above. It occasionally causes concern due its habit of burrowing into soft mortar between bricks, but is rarely if ever a problem. If you watch carefully, you can even see the females using special prongs on their faces to tamp the mud into position after bringing it to the nest as pellets held in their mandibles.

The second is a very different species, the parasitic bee Nomada marshamella.

Nomada marshamella posing helpfully on my finger.

N. marshamella is one of the commoner species in this genus of parasitic bees, and this specimen was seen crawling in through an open window. Like other Nomada, it is an effective wasp mimic, looking more wasp-like than bee-like, and can be confused with N. goodeniana (including by me, though courtesy of Nick Owens, I now know that they can be separated by the colour of the wing-base or 'tegula' - orange here as opposed to bright yellow). It is a parasite of the common mining bee Andrena carantonica (and possibly the rarer A. trimmerana), though interestingly none of those that I have so far recorded in the garden (which doesn't mean they aren't there of course). This is also a good point to plug the excellent BWARS (Bees, Wasps and Ants Recording Society) website, including a very fine photographic gallery.

Finally (I'm being relatively brief today), I'd like to introduce my 20th garden-bee identification of the year so far, a female Osmia caerulescens (I originally thought these photos were of Lasioglossum morio which has also been recorded here - thank you again to Nick Owens for letting me know).

Osmia caerulescens female approaching Lotus corniculatus flowers, tongue at the ready...

Osmia caerulescens female on Lotus corniculatus flower - note the blue-green metallic sheen and pale hairs.

This small bee is widespread and common (I'm pretty sure it's been using the garden for a while but I hadn't managed to get a close enough look), and feeds from a wide range of flowers. Females nest in existing holes such as in dead wood, including fence posts, and masonry (we have plenty of both) where it closes the hole with a plug of chewed leaves, and is well-known from both gardens and woodland edges.

So, just three of 20, but I hope they provide a little inspiration if you are thinking about planting bee-friendly plants and other garden features - for example, we have a small patch of open sand created to encourage invertebrates that like this sort of thing; it is possible to create a diverse habitat structure even in a tiny rectangle of Britain like ours. The list so far is below and I expect to identify more, especially as I have plenty of hosts with no parasites and parasites with no hosts...

• Bombus terrestris
• Anthophora plumipes
• Apis mellifera
• Bombus lapidarius
• Andrena haemorrhoa
• Osmia rufa
• Bombus hypnorum
• Bombus pascuorum
• Nomada flava
• Lasioglossum calceatum
• Lasioglossum morio
• Bombus lucorum
• Colletes daviesanus
• Sphecodes monilicornis
• Hylaeus communis
• Andrena flavipes
• Anthidium manicatum
• Hylaeus confusus
• Andrena labialis
• Osmia caerulescens
• Nomada marshamella