Bumblebee flowers, which to choose? And their ecology

Most popular bumblebee flowers in late July

The garden centre is the obvious place to compare the attractions of different garden flowers. And, I discover, a good place to observe the ecology of bumblebees.

The main bumblebees on view today were white tailed: B terrestris and B lucorum

The most popular flowers by a mile were all colours and varieties of Salvia:

But if you look closely you can see that the bees are cheating the flowers by robbing nectar through a hole in the calyx [sepals] or corolla [tubular petals]

In the photos, nearly every flower has been broken into. 

 


The next most popular flowers were Echinacea



And after that: Penstemon, Veronica, Alstomeria, Cirsium, Helenium, Physostegia

and the Common Carders favoured Nepeta

Where to find bumblebees in late July

In Gardens

My neighbour's Lavendar is buzzing with B terrestris, lapidarius, pascuorum and pratorum, the early bumblebees are still plentiful here. Also a cuckoo bumblebee, R rupestris

In Grassland

The bramble flowers still attract B terrestris 
but the main bumblebee interest is around scabious: B lucorum, 

B terrestris, 

B pratorum

 And these oddities: a cuckoo bumblebee B rupestris?

And a faded B terrestris?

B pascuorum on thistle

Flowers for bees in July

Which flowers attract bumblebees this July?

I've seen fewer bumblebees in my garden and the countryside in the South West this week.

 Cue a visit to the nearby Botanical Garden to find which bumblebees are active and which flowers are providing pollen and nectar.

  Hebe flowers from New Zealand seem the most attractive; here's a Bombus lucorum [queen?] heavily weighed down with bundles of pollen

Also among the Hebe flowers, there were tree bumblebees: Bombus lapidarius 

Another popular flower is the   St Johns Wort : Hypericum which attracted common carder been, Bombus pascuorum carrying red pollen loads

 

And Bombus lucorum, here carrying a yellow pollen load

And Japanese anemones

Do bumblebees hold grudges?

Do bumblebees hold grudges?

Late June and the Cotswold brambles are coming into flower. 

attracting our smallest bumblebees, like this Bombus pratorum worker

and our largest, like the White-tailed bumblebees, Bombus lucorum, 

 each lucorum bee seems to linger on the bramble flower to savour every single drop of sweet nectar. Sometimes colliding with bramble thorns as they search for new flowers. Are they intoxicated? Sometimes they seem a little dizzy and poorly coordinated as they fly between the thorns.

I startled one lucorum sunning itself on the grass. It flew up into the brambles and barged a fellow lucorum bumblebee that was gorging on bramble nectar. She was taken unawares and fell like a stone onto the grass. Moments later she reappeared and smacked into the offending bee, causing it to fly off in search of another flower.

Could they be from the same colony? Or were they rivals for the food which seemed plentiful. All around, there were open bramble flowers; why pick on the bee on this one particular flower?

Should I be surprised? Bumblebees are active

September bumblebees

White-tailed bumblebees are still collecting pollen, 

Here's a white-tailed bumble on a windy day on 18th September, feeding on an evergreen Hebe shrub, [sapphire variety] in a park in Bristol:

Around mid-September I expected queen white-tailed bumblebees to be seeking a quiet underground tunnel to overwinter. In fact I photographed a queen bee doing exactly that back in August. 

But this worker bee indicates otherwise.

She's carrying a pollen basket, signifying that she's still collecting pollen for her colony. After many mild winters and speculation about global warming maybe I shouldn't be surprised at this even on mild days in October. 

I guess you're still going to find bumblebees if you look in October and November. 

But if you do see one, is it a queen about to hibernate, a lone survivor or a worker and member of a persistently active colony?

Menawhile here's a common carder been on white deadnettle in the same park

The strong wind was causing this bee considerable problems.

And here's a common carder bee feeding on a Fuchsia in a Bristol garden after 5pm. 

That's a long day's work.

Bumblebee sightings

Where bumblebees go in September

Here in Gloucestershire there are two places where you can reliably find bumblebees, well OK after borage, teasel, Corydalis, laurel and Buddleia...

  In gardens around here an annual that returns every year is popular with white-tailed bumblebees: Sedum

It's easy to grow and would fit into a small space like a car port.

Out in the countryside 

there seems to be a lot of unclaimed nectar among the white and red clover, trefoil and vetches which are still in flower. 

Is it too windy out in the fallow strips beside the ploughed fields?

The place where I can reliably find bees is by the stream where the mint grows.

Do bumblebees fix on just one source of nectar? 

Sometimes bees can be seen flying from one flower to another of the same species, usually starting from the bottom and working there way upwards. 

Do they overlook other possible sources in a bid to save time? 

Just occasionally I see a bee darting from teasel to corydalis to cranesbill to take tiny sips. 

Is this a sign of desperation due to falling nectar production in late summer?

There are some tree bumblebees around; I just haven't been able to catch one on camera. 

I am trying to find bees other than common carder bees and white-tailed bumblebees.

Bumblebees: using all the senses

Sight, sound and smell are all needed 

 to track down bumblebees in September. 

On windy days like today bee flight can seem erratic. Even if you catch sight of a bee it can rapidly disappear.
   Listening to the buzz may help you to tell wasps, flies and bumblebees apart. The tone of a bumblebee is deeper and by listening carefully you can work out the bee's speed and direction. There are probably differences in tone between bumblebees that would help you identify which bee it is.
  Smell is helpful too in noticing when flowers are producing nectar. Stand by a fruiting ivy in September and you can smell the nectar on the leeward side [the opposite side to the wind].
Yellow Corydalis is a self-sown plant [also known as a weed] attracting bees during mild weather in mid-September:

On mild windy days, yellow corydalis which grows beside walls offers a source of nectar that's less blown about.

The other reliable fall back for bumblebees in rain is white deadnettle:

which seems to provide nectar even on windy and wet days:

Maybe it's more productive than clover and scabious which don't seem to be visited as often in September.

Best time for bees

The best time to watch bumblebees

When's the best time to watch bumblebees in September? Is it on sunny mornings? I've noticed that white-tailed bumblebees and common carder bees seem active at 8am when the sun's shining.

  In my garden, it's the self sown weeds that are attracting the bumblebees at the moment:

Evening primrose

Sweet Pea

Teasel

Do Bees behave differently in September?

This morning I watched a white-tailed bumblebee racing from one evening primrose flower to another without collecting nectar or pollen, almost bumping into a carder bee that was leaving a flower, revisiting flowers it had just rejected, flying towards other plants with flowers but rapidly flying onwards. She gave the impression of being desparate for a fix of sugar-containing nectar.

  I wondered if the combination of warm sun, cool shade and less nectar was affecting her behaviour; the available nectar-containing flowers seem to have been well visited by bees and hoverflies.

  On the other hand I watched a white-tailed worker get caught up in a strand of spider's web and after being held for a few seconds she flew strongly enough to free herself.

A carder bee drinking from a blue sow-thistle

Carder bees will chase off common blue butterflies and small coppers who were feeding on white clover:

Clover is about the only nectar-producing flower in grass meadows around here.

September bumblebees

Where do bumblebees go in September?

You don't see as many bumblebees in late summer but they haven't all disappeared. 

Where to look?

  4 places you could try

1 Ivy

IVY is in fruit throughout September so you could look there but just at the moment wasps and hoverflies seem to dominate:

There are some bumblebees,

 I wonder if wasps are competing with bees and winning, though I think the balance may change as wasps die back in autumn.

2 Garden and wasteland flowers: 

such as the ever abundant Buddleia 

And lavendar

  But also wasteland plants like green alkanet and white deadnettle that are attracting common carder bees:

And of course garden centres and open gardens. 

                                     3 Beside streams:

The much maligned alien plant which aggressively colonises streams and rivers.  In Somerset this week, this is one of the best places to look: the tallest annual in Britain has established a niche: Himalayan Balsam, Impatiens glandulifera

 It may be a musty-smelling invader that flings its seeds explosively up to 4 metres through the air but it's an ideal source of nectar.
In Somerset you find Common carder bees and white-tailed bumblebees climbing inside the policeman helmet-shaped flowers. 

                                     4 In lawns and in the undergrowth:
You might look in the undergrowth, where queen bees are looking for places to hibernate.

Here's a white-tailed queen bumblebee burrowing a hole in a lawn in Somerset.