The wondrous diversity of garden bees

About a month ago, I posted some musings about what can be found in a bee-friendly garden - after all, problems with a decline in pollinators are well documented and gardens can be an essential habitat. So, after a few weeks of largely warm dry weather (not typical for April in England!), I thought I'd see what was using our little suburban strip of goodness...

The Hairy-footed Flower Bee (Anthophora plumipes) remains active (particularly females) and are now visiting the wider range of plants that are available - lavender is very popular. However, these have probably been outdone on the activity stakes by the Tawny Mining Bee Osmia rufa. These have spent the last week or two mining soil from the damper parts of the garden (there's a flurry of activity when the garden has been watered) and taking it to the bee log where the drilled holes have been well used. These contain cells formed in sequence with the entrance sealed with packed soil. I shall await the appearance of the early summer generation soon; the log will be stored in the shed to over-winter from late September until being hung up again in the spring to await emergence of the next generation. Not only that, but they are great pollinators, especially of fruit trees, and our garden has apple, peach, quince and cherry either in or adjacent to it.

Female Osmia rufa basking on a paving slab - note the short prongs on the face just below the antennal bases; these are used to tamp mud into place.

 

Mmmm... soil

Back to the log

Spot the completed holes - and the retreating bee-bottom just right of centre

Of course, there are plenty of other bee species which could use a suburban garden, and several of these (some of which I have yet to identify as I'd need to capture them) have indeed appeared. Some are commonly seen like the the Buff-tailed Bumblebee Bombus terrestris and of course the essential Honey Bee Apis mellifera; others may be less familar e.g. leaf-cutters of the genus Megachile, and other genera such as Andrena and Lasioglossum. Some very general observations suggest that many of these are nesting elsewhere but using our garden a source of food i.e. I have seen several species which appear to always fly in, feed, then fly out again.

Another bee-bottom, this time approaching a clematis flower

A specimen of Bombus terrestris found deceased - note the sting rarely deployed in life

A small bee, possibly of the genus Lasioglossum

Bee caught in flight; probably Andrena haemorrhoa

Most of this activity is, at least on the surface, pretty harmonious (feed, collect, breed), but nature being nature, that's not the whole story - where there are breeding adults, there are eggs and larvae, and hence parasites. For example, Fabricius' Nomad Bee Nomada fabriciana parasitises Andrena bicolor and I have found both in the garden, the latter on dandelions. Similarly, the nests of Osmia rufa are parasitised by the jewel wasp Chrysis ignita, which I have again recorded in the garden, although I haven't yet found a specimen that would stay still long enough for a clear photo. I'll also be on the lookout for more host-parasite pairings, so do watch this space for updates.

Nomada fabriciana - note the red and black antennae (and the unwanted household fluff)

To finish, a couple of days ago I found another specimen dead on the window-sill - this has just been ID'd as the common small bee Lasioglossum calceatum - enjoy the images...

Dorsal view of L. calceatum

Wing veins - on the forewing, vein 2m-cu is weakly S-shaped and does not bulge outwards at the rear end. Hence this is not a species of Colletes. Also, the cross-veins become thinner towards the wing-tip and the basal vein is strongly curved.

Abdominal tip (5th tergite) with the small teardrop-shaped area surrounded by dense hairs. Pale flattened hairs at the side of the segmental bases.

A bit out of focus, but clearly with pollen-collecting structures (scopa)