A strange title for a blog post you might think?
(You’ll just have to read to the very end of the post to understand).
At this time of year, it becomes pretty-obvious that whilst some might pigeon-hole (hur hur) me as a “birdwatcher”, I am not – nor have I ever been one.
Oh sure, I do like watching birds. They’re pretty obvious things to see - in general.
They sing, shout, squawk and of course fly .... and so make themselves pretty conspicuous.
But at the height of the summer, the more inconspicuous, smaller critters tend to grab my attention.
Heliophiles quite often. Like myself.
Whether that be dragonflies, bees, butterflies or perhaps even wasps.
Let's deal with bees briefly.
I suppose that if you asked many people to name as many “types of bee” as they could, they might struggle to get beyond “honey bee” and “bumblebee” but there are something like 270 species of bee in the UK, of which only one is a honey bee and only something like only twenty-one are bumblebees.
That leaves approximately two-hundred and fifty other species of bee in the UK – often known as solitary bees, or more correctly – non-social bees.
Now my favourite British bee of all is a tiny, beautiful, gold-coloured solitary bee (Osmia caerulescens) – the blue mason bee (see below)
but we have none nesting with us at our current home – so I’ve been instead watching some other, very specialised non-social bees in the garden for a week or so now – leaf cutter bees – or Megachile bees.
Leaf –cutter bees are great fun to watch.
They are so-called as the females cut little discs from leaves (and rose petals in our case) to line their nest cells with.
About the size of a honey bee (maybe a bit smaller but ‘chunkier’) they can be seen during the summer months air-freighting bits of leaf and petal back to a “secret” nest.
If you get an exceptional view of a leaf-cutter female (without a leaf disc in legs), you may see that she has an orange or golden scopa (pollen brush) under her abdomen – this is quite indicative of leaf-cutters.
As I’ve stated, leaf-cutters are “non-social bees”. This doesn’t mean they don’t nest in groups (that’s why solitary bees is a bit of a misnomer), it simply means that each female builds her own nest independently of other individuals of the same species – even if they can nest in what appear to be “colonies” – especially if you construct (or buy!) a bee hotel for them to nest in. (See below).
Most leaf-cutter bees prefer to nest in existing cavities (in wood or masonry) but some, if pushed, will excavate burrows in the ground.
Each nest cell will be lined (and enclosed) with leaf discs; and each will contain a food supply of pollen and sometimes nectar for the developing larva to feed on. The singular egg is laid onto this food source brought back to the nest by the female, before she seals the cell with more pieces of leaf and starts another.
The leaf-cutter bee will stick these discs of leaf and petal together (often rose leaves and petals) using a mixture of the leaf’s sap and the bee’s saliva.
The egg develops into a full-grown larva pretty quickly during the late summer. The fully-fed larva then spins a silk cocoon in which it overwinters.
Pupation will occur in the late spring & the resulting adult leaf-cutter will emerge from the nest from the end of May onwards.
As is normal in these cases, once the adults’ work is done, they’ll die.
Their offspring will never see them.
There will be no “parental care”.
ALL the bees’ gene-pool is locked up in these little leafy-cigar-like cells, ready to emerge as the new (ONLY) generation in late spring the following year.
It is only the female that exhibits the orange scopa. Likewise it is only the female that cuts discs from leaves, using her mandibles.
It is a fascinating process to watch, I think – and very amusing.
She’ll select a leaf, (a fresh one often), land on it and quickly slice a scalloped or circular-shaped section from the leaf edge.
Invariably, like a cartoon character sawing a circle around himself on a wooden floor, the female bee will make the last cut, and leaf disc and bee will fall ground-wards together.
She’ll be holding onto it though, with all six legs – and like a miniature helicopter she’ll soon be climbing into the sky with her leaf disc – and heading towards her nest.
And that is exactly what these bees remind me of, with their air-freight of chlorophyll – helicopters lugging a bit of cargo around underneath them.
It’s clearly some effort. If you are lucky enough (like me) to have “colonies” in the garden each year to watch, you’ll notice that some leaf-carrying females have to stop and rest en-route to their nest.
There are, as I say, eight (I think) species of leaf cutter bees in the UK.
They are harmless (the females will only sting like all bees if you roughly handle them. You’d really have to squeeze leaf-cutter females for them to sting and males can’t (of course) sting at all.
All non-social bees are as (if not more) useful in terms of pollination (of our crops and flowers) as our more “famous” honey bees and bumblebees.
So yes… eight species (of leaf-cutter bee) there are - but probably only three species you’ll encounter regularly, (should you look), especially in the south of England.
Megachile centuncularis (deep orange scopa –scarce in Scotland and Ireland),
M. versicolor (orange scopa – widely distributed throughout the UK) and
M. willughbiella (golden scopa – common all over the UK and Eire).
You’ll see them (if you spend as much time as I do outside and look) from early June (after the mason bees have done their business, often) until late August.
But you can do better than that if you’re lucky enough (like us) to have a garden.
Attract them TO your garden.
Just take an empty tin can and fill it with 6 inch lengths of hollow bamboo poles, glued to the inside of the can.
String the ensemble up so that it faces south, catches the full sun (more important for leaf-cutters than mason bees) and ensure that it tips slightly down so that the tubes don’t tend to collect water, should it rain.
Or if you really can’t face all that work (like me!) garden centres sell “bee hotels” these days – for a few quid.
If you do the above - invariably you’ll have beautiful, amusing-to-watch leaf cutter bees carrying about bits of leaf all summer long in your garden.
A win for you and a win for the bees.
Easy as ABC. (DE).
“I bees see. (tee-hee)”…..
As is always the case, all photos on this site are mine. Please contact me if you’d like to know technical details.