Tag Archives: scorpion vetch

The winter solstice – a day of sunshine – with flowers, butterflies and bumblebees

When the short day is brightest, with frost and fire,
The brief sun flames the ice, on pond and ditches,
In windless cold which is the heart’s heat,
Reflecting in a watery mirror
A glare that is blindness in the early afternoon.

(from Little Gidding, the last of TS Eliot’s Four Quartets)

low midwinter sun behind pine trees at Roundham Head
Low midwinter sun behind pine trees at Roundham Head – silhouettes and shadows

 

We had a lot of grey, wet weather towards the end of last year, and very little sunshine. A few days before Christmas, however, the forecast predicted a bright, dry and relatively mild day, so I took the opportunity to get over to Roundham Head in Paignton to see what flowers and wildlife might be about. It’s a journey of about ten miles and that morning I took the bus, enjoying the long views across the surrounding countryside. Paignton is a seaside holiday resort but it looked distinctly “out of season” when I arrived, despite the sunshine and blue sky. A few people were walking along the promenade; they were well wrapped up even though it wasn’t a cold day. The little harbour was quiet; small boats bobbed on the water protected by the old stone walls and a gang of turnstones skittered like mice at the water’s edge. Molly Malones food shack was closed for the winter and the booths normally touting fishing excursions were empty.

I walked up suburban streets to get on to the northern side of Roundham Head, the flat-topped, cliff-lined, grassy promontory that protrudes into the waters of Torbay. A line of tall pine trees straddles the first part of the headland and the low sun rendered these as silhouettes casting long shadows across the grass. The path around the promontory follows the cliff edge with views to the sea below and a seal teased me by briefly raising its shiny black head above the water. Eventually I came to southern side of the Head and the gardens that were built in the 1930s partly to stabilise the cliffs. Steep zig zag paths track up and down between flower beds planted with exotic species that, between them, provide colour throughout the year. There are benches should you wish to rest or enjoy the views over Torbay and the shelter, the proximity of the sea and the south facing aspect of the gardens generate a mild microclimate.

low midwinter sun over Goodrington Sands
The low midwinter sun over Goodrington Sands

 

It was the winter solstice that day, the shortest day in the northern hemisphere, the day when darkness begins to give way to light. From the southern edge of Roundham Head, above the gardens, I could see the sun hanging very low in the pale wintery-blue sky casting its light across the beach at Goodrington Sands creating a silvery mirror on the water. Even though this was midwinter, there were plenty of flowers around me in the gardens and the low sunshine created surprising effects. Its intense golden light gave a softness to the air and enhanced flower colours to an almost psychedelic extent. Banks of bergenia acquired a pink brightness worthy of late 1960s San Francisco and the scorpion vetch (Coronilla valentina) that flourishes all over the gardens glowed with a lemon-yellow light.

I paused by a clump of bergenia, enjoying the warmth of this sheltered spot. A small bumblebee, ovoid and furry with black, white and yellow stripes, soon appeared, moving among the bright pink flowers looking for food. Quickly tiring of the bergenia, it flew to one of the white funnel-shaped flowers in a large clump of shrubby bindweed (Convolvulus cneorum), burying its head in the base of the bloom where it stayed, drinking nectar. Based on size and appearance this was probably a buff-tailed bumblebee worker. A drone fly also took advantage of these flowers resting near the mass of golden yellow stamens. Soon after, I got a surprise when a butterfly landed briefly on the bergenia before flying off. It circled for a while before settling on a wall to bask in the sunshine showing me that it was a painted lady, with its characteristic wing coloration of orange/buff, black and white. An insistent buzz announced the arrival of a large bumblebee, black with orange/buff coloured bands. This was a queen buff-tailed bumblebee and she proceeded to feed from the bergenia. I had two more sightings of large furry queens on these pink flowers.

Another plant that flourishes here is rosemary and extensive curtains of the herb cascade from several borders, their slate blue flowers glinting in the sunshine like diamond chips. Rosemary is in flower here for several months across winter providing pollen and nectar for insects and I saw several buff-tailed bumblebee workers moving quickly about the flowers, their pollen baskets well loaded. They were very jumpy and flew off when I got too close. For a short time, they were joined by another queen carrying a small amount of grey pollen, also a basking, but rather worn, red admiral butterfly with its bright red and white patterns on a black background.

By mid-afternoon, cloud began to bubble up to the south, and eventually a slab of grey cloud obscured the sun. The temperature dropped noticeably, the wind got up and the bees went off to shelter, bringing observations to a close. I made my way back to the bus station pondering what I had seen.

It still surprises me to see butterflies in the winter. I have seen them here before in December and January but in my mind these brightly coloured insects signify summer. Although most red admirals are thought to migrate to the UK from North Africa and continental Europe, a few are thought to be resident now that mild winters are becoming more common. These residents can be seen flying and feeding on gentle winter days. The painted lady also migrates into the UK but is thought to be unable to survive our winters, so the one I encountered is unlikely to see our spring.

What about the bees, aren’t they supposed to be in hibernation at this time of year? Well yes, most bees are, but based on my observations of buff-tailed workers collecting pollen in December, there must be winter active colonies at Roundham Head. I first saw worker bumblebees here in January about five years ago and since then I have seen them at a similar time each year, so this is a well-established phenomenon. There are presumably queens in their nests laying eggs supported by these workers. These queens would have been produced in the previous October to mate with males at emergence. Last year I did see male buff-tails here in December so perhaps these were survivors of the late autumn emergence.

There is abundant evidence now from a variety of sources that colonies of buff-tailed bumblebees are active in the winter across the southern part of the UK. Two factors seem to be important: winter weather should not be too harsh and there should be plenty of flowers to support the colonies.

worker bumblebee on shrubby bindweed
A worker bumblebee on a shrubby bindweed flower

 

drone fly on shrubby bindweed
A drone fly on a shrubby bindweed flower

 

queen bumblebee on bergenia
Queen buff-tailed bumblebee on bergenia

 

painted lady butterfly
painted lady butterfly

 

painted lady butterfly on bergenia
painted lady butterfly on bergenia with wings closed

 

worker bumblebee on rosemary
Worker bumblebee with pollen on rosemary

 

red admiral butterfly
red admiral butterfly – note the damaged wings

 

The meaning of a winter bumblebee

As I drove back from Paignton, the low sun cast long shadows across the sensuous folds of the South Hams hills. But the sunshine was deceptive; the temperature outside was 7oC and in the distance, there stood Dartmoor sprinkled liberally with snow like icing sugar on a cake. It was our first taste of winter and, inspired by Mark Cocker’s recent Guardian Country Diary on “The meaning of a bumblebee”, I had been to Roundham Head in Paignton to see what insects were about on this cold day.

grevillea
Grevillea

 

There were pockets of warmth in sheltered corners of the Roundham Head Gardens but generally it felt cold in the wind and by the time I got back to the car my hands were numb. Despite the conditions, there were plenty of flowers about: yellow scorpion vetch in profusion, hanging curtains of rosemary with a few grey-blue flowers, exotic pink and white grevillea, purple spikes of hebe and the pink cup-shaped flowers of bergenia.

painted lady butterfly in winter
Painted lady butterfly on rosemary

 

What about the insects? I saw a few large black flies and one hopeful hoverfly but my biggest surprise was two smart looking painted lady butterflies enjoying the sunshine. Seeing bumblebees required patience but eventually I was rewarded by the appearance of a few buff-tailed bumblebee workers filling their pollen baskets by probing the rosemary, grevillea and bergenia. I also saw one plump and furry buff-tailed queen meticulously working the bergenia flowers before she flew off.

buff-tailed bumblebee worker 2
Buff-tailed bumblebee (B.terrestris) worker on rosemary

 

 

buff-tailed bumblebee worker 3
Buff-tailed bumblebee (B.terrestris) worker on bergenia. The pollen baskets are visible.

 

buff-tailed bumblebee queen1
Buff-tailed bumblebee (B.terrestris) queen on bergenia

 

Mark Cocker attributes his surprise sighting of a bumblebee in Norfolk on January 1st to anthropogenic global warming and anomalous weather linked to El Nino but there must also be suitable forage for the bumblebees if they are to be active in winter and survive. The British penchant for gardening and for planting winter-flowering shrubs seems to supply this forage.

tamarisk by torbay
The view across Torbay from Roundham Head Gardens with tamarisk in the foreground

 

I visited Roundham Head Gardens on January 15th 2016

Winter-active bumblebees in a Devon seaside garden

It was a sunny Sunday morning in January last year and we were walking through public gardens at Roundham Head in Paignton, South Devon. Passing a bank of flowering rosemary, we spotted a bumblebee. Surprising? Well yes, bumblebees are supposed to be hibernating in January, aren’t they?

Worker bumblebee on veronica in winter
Worker bumblebee on Hebe (January 4th 2015)

 

Fast forward 12 months to January 2015 and we are passing through these same gardens. As we enjoy the sunshine we notice another bumblebee, feeding on a very smart looking purple Hebe. This time we take a few photos before the insect flies off and we confirm that it’s a worker bumblebee with loaded pollen baskets.

I was very intrigued by these observations and felt compelled to find out more, but first I need to tell you about the gardens as they are a bit special.

Roundham Head

Roundham Head
Roundham Head from the southern side showing the Cliff Gardens above the esplanade with the red cliffs on the far right.

 

The popular seaside holiday resort of Paignton is enclosed by urban sprawl and Roundham Head is a surprising botanical oasis in this part of South Devon. To the North of the headland is Paignton harbour with its many tempting summer treats (wildlife and angling cruises, Molly Malone’s seafood stall and so on), all sadly closed at this time of year. To the South is Goodrington Sands, fine for a pleasant summer’s dip but, in winter, a dog and doggy walker’s paradise. The headland itself is surrounded by steep red cliffs and is grass-topped with a fine stand of pine trees offering Mediterranean views across the Bay to Torquay.

Pine trees at Roundham Head, Paignton
Pine trees at Roundham Head – Mediterranean view?

 

Goodrington Sands
The view from the gardens towards Goodrington Sands

 

The cliffs on the southern side are where we find the Cliff Gardens (sometimes called Paradise Gardens). A maze of flower beds and zigzag paths ascend and descend the cliffs and there is an occasional secluded seat for those who wish to contemplate the sea or simply rest. The Gardens themselves seem to enjoy a very mild microclimate. Many of the borders are protected from the wind and for much of the day, the sun, when it is out, warms the soil. The Gardens are home to tender, sub-tropical plants and there are flowers throughout the year. The predominant colour in January is yellow from the scorpion vetch (Coronilla valentina, a native of the Mediterranean ) which thrives here.

scorpion vetch
Scorpion Vetch

 

My visits to the Cliff Gardens

Five days after the most recent sighting, I am back in the gardens with my camera, looking for bumblebees and getting a few odd looks from passers-by. I had scoured the forecasts on the Met Office web site and the weather today was predicted to be sunny and mild (12oC, good for bees), although rather gusty and getting windier (not so good for bees). It is a bit of a gamble but I decide to risk a visit.

worker with pollen
Worker bumblebee on rosemary (January 9th 2015)

 

When I reach the Gardens I take the first path, half left downhill, where there is a huge bank of rosemary facing in to the sunshine, enveloping the border and the wall below. It’s a mass of small blue flowers and I immediately see a worker bumblebee on the blooms, its pollen baskets laden. It’s either a buff-tailed (Bombus terrestris) or white-tailed (Bombus lucorum); the workers of both species look similar. I zigzag up and down the paths and don’t see any others until I come across a large island border just below the top of the cliffs. This is filled with flowering rosemary, some tired-looking bergenia, and more scorpion vetch. There are two or three queens here, definitely Bombus terrestris based on their buff-tails, feeding from the bergenia and rosemary flowers. They don’t use the vetch. It’s quite gusty but they are very determined and forage despite the wind. I feel sorry for them: one gets blown off a flower stem another seems to shelter for a while but she could be warming up. Eventually I give up as the wind is too strong.

Queen bumblebee in winter
Buff-tailed queen on rosemary – by comparison with my hand she is about 2.5 cm long (January 9th 2015)

 

Bumblebee queen on bergenia
Bumblebee queen on Bergenia (January 9th 2015)

 

Despite the weather, it was worth the visit but I now have many questions. How many bees and how many colonies? Are they all buff-tailed? Where are the nests? Why is there a mixture of workers and queens?

……………………….

So, two weeks later, the weather again looks possible and I am back. The temperature today is ~9oC, a mixture of sunshine and cloud with a light wind. There was frost the night before in Totnes and, although it probably didn’t frost in Paignton, I wonder how the lower temperatures will have affected the bumblebees.

Bumblebee worker on Grevillea
Bumblebee worker on Grevillea (January 23rd 2015)

 

In fact all seems to be well. I see workers with pollen on the hanging rosemary, on the hebe and on a shrub covered with unusual spiral-shaped red flowers that I identify later as Grevillea, a native of Australia. Some of these workers fly at me as if to shoo me away; perhaps they feel threatened. At the island border I see a worker and several queens feeding off the rosemary. At one point, a queen flies to the ground where she wanders about apparently looking for something. There are no bumblebees on the bergenia today but, astonishingly, I see a red admiral butterfly on this plant.

bumblebee queen on rosemary
Buff-tailed queen approaching rosemary (January 23rd 2015)

 

Red Admiral on bergenia
Red admiral (a little tattered) on Bergenia (January 23rd 2015)

 

I don’t think I learnt very much from this visit except that this is a very mild spot with plenty of bee forage even in midwinter.
………………………..

So, I decide to visit again just under two weeks later on another sunny day. In Totnes the air is very cold (~5oC) but, when I get to Roundham Head, the sun is shining directly on the Gardens, it feels quite warm and there is little or no wind. My experience today is different: I don’t make any definite sightings of queens but I do see several workers and with one exception these are all feeding on rosemary. The workers differ considerably in size but that’s a common observation. They all look in very good condition; their wings are not frayed so they are relatively young. While I stand near the Grevillea, a large bee, probably a queen, flies at me, does a few circuits around my head and then flies off. I get the impression I am being warned but perhaps I am overreacting!

Bumblebee worker on rosemary 2
Bumblebee worker approaching rosemary (February 4th 2015). If you click on the photo you should be able to see the brown band before the white tail (typical of B. terrestris)

 

Bumblebee worker on rosemary 3
Bumblebee worker on rosemary (February 4th 2015) – note the brown band before the white tail (typical of B. terrestris). I am not sure where this one found the yellow pollen?

 

Later, when I have a good look at the photos of the workers I notice that they have a narrow brown band just before the white tail. This is typical of buff-tailed bumblebees and is not seen on white-tailed workers so it is likely that the active nests are buff-tailed (Bombus terrestris).

What does it all mean?

Over a period of about four weeks in the middle of winter, I have been able to see buff-tailed bumblebee queens and workers quite easily at this location. I get the impression, however, that there are actually not very many about: perhaps four queens and eight workers?

The presence of foraging workers as early as January 4th indicates an active nest. I have no idea about the site of the nest but I assume there is a queen, tending larvae and being fed by the workers. The nest was probably established in the last few months of 2014.

At this time of year, bumblebees typically hibernate but since the 1990s there have been reports of winter-active colonies of mainly buff-tailed bumblebees, largely confined to the southern part of the UK. Speculation has been rife as to what is causing this change in behaviour. Some suggest it is linked to warmer winters associated with climate change. This can’t be the whole story as, according to Dave Goulson, bumblebees in Brittany do not exhibit the same winter activity. The magic ingredient may be the availability of winter forage in the UK linked to the British passion for gardening and planting winter-flowering shrubs.

The sub species of Bombus terrestris found in some parts of continental Europe can also have two nesting periods a year, when climate is suitable and winter forage is available. A litter is produced across spring and summer and fertilised queens find suitable places to hibernate for 2-3 months before emerging in late September to set up new colonies across the winter. The Roundham Head colonies probably arise from fertilised queens produced during summer 2014 who emerged after a few months rest to set up winter nests. The microclimate and the abundant local forage make this activity possible.

There has been speculation that the continental sub species of Bombus terrestris, imported for pollinating vegetable crops, may be escaping and establishing itself in the UK. Given that this sub species sometimes produces two generations, it is possible that these continental bumblebees could be the winter-active bumblebees seen in the UK. The Roundham Head colonies, however, have the physical characteristics of the British sub species so they cannot be foreign escapees.

What about the queens that I saw? Here it all becomes rather uncertain. They could be founding queens from active autumn/winter 2014 nests coming out for a feed or they could be new queens generated by these nests. Alternatively, they could be queens from summer 2014 nests emerging from hibernation on a warm day. What might happen to these summer 2014 queens is also a bit unclear. They might set up new nests if the weather stays warm. Perhaps if the weather turns cold they return to hibernation after feeding but, it is not known if this actually occurs.

So, more questions than answers, but there definitely are active winter nests at this favourable seaside spot. It’s been fascinating and great fun to observe these bees and I shall continue watching over the next few months to see what else I can learn.

I should like to thank Dave Goulson (University of Sussex) and Tom Ings (Anglia Ruskin University) for helpful comments.

Goodrington Sands
Another view over Goodrington Sands at low tide