National Insect Week 2023: Celebrating carder bumblebees
By Miranda Shephard, Information Officer
There are around one million known species of insect, and probably quite a few more waiting to be discovered and named! This week it’s time to celebrate them during National Insect Week 2023, so we thought we would take a closer look at our favourite type of insect – the bumblebee! And more specifically, the beautiful carder bumblebees.
Five out of our twenty-four UK bumblebee species are given the name carder bumblebee. This is due to the similarity between the carding process used by people to separate and arrange the fibres of materials, such as wool and cotton, and the way in which these bumblebees arrange nesting material over and around their nests. All five carder bumblebee species tend to nest above ground, among tussocky grass or other dry patches of long vegetation, where they use their legs and mandibles to comb and coax vegetation into a protective insulating layer.
Red-shanked carder bumblebee
The most distinctive carder bumblebee is the Red-shanked carder bumblebee (Bombus ruderarius) which, at first glance, could be mistaken for the more common Red-tailed bumblebee (Bombus lapidarius). However, the clue is in the name as the Red-shanked carder bumblebee does indeed have red hairs on its legs. They are also a bit fluffier and their red tail is more orange than red compared to the Red-tailed bumblebee. This carder bumblebee is quite rare but, if you’re in south and central England, Wales or the Inner Hebrides, it’s always worth keeping an eye out for red hairs on legs.
Shrill carder bumblebee
The carder bumblebee group includes one of our rarest bumblebees, the Shrill carder bumblebee (Bombus sylvarum). Named for its high-pitched buzz, this species is only found in five scattered populations across the south of England and Wales. Usually only seen from May to September, the key features to look out for are the black band between pale straw coloured hair on the thorax and a ginger orange tail at the end of more straw coloured hair on the abdomen.
Common carder bumblebee
Next up are three (one common and two rare) ginger brown carder bumblebees, which can sometimes be confused with each other. Let’s start with the one that many people will be most familiar with.
The Common carder bumblebee (Bombus pascuorum), as their name suggests, is one of our Big Eight common and widespread species. Often found in gardens and across the countryside, this ginger brown bumblebee can be seen from March all the way through to October in many areas. This is a variable species with both very pale blonde and much darker haired individuals. A key feature is the presence of black hairs which, even in the very palest individuals, will be present somewhere on the thorax or abdomen. Common carder bumblebees are also quite messy looking, with longer hair than the next two species.
Moss carder bumblebee
A much neater, sometimes described as velvety, and brighter ginger blonde carder bumblebee, the Moss carder bumblebee (Bombus muscorum) is a rare bumblebee. This carder bumblebee is mainly found in coastal areas in England and Wales but can be more widespread in Scotland. Usually seen between May and September, the Moss carder bumblebee is more likely to be spotted in flower-rich countryside than gardens. Unlike the Common carder bumblebee, this bumblebee never has black hairs on the thorax or abdomen. A beautiful and striking colour variation, with a deep gingery red thorax, can be found on some of the islands around the UK.
Brown-banded carder bumblebee
Last, but definitely not least, is the Brown-banded carder bumblebee (Bombus humilis). Another of our rare bumblebees, the Brown-banded carder bumblebee is confined to the south of England and Wales where it can be seen between May and September. A key feature of this species is the ginger brown band across the top of the abdomen which is a similar colour to the thorax. Look out for the pale blonde hair patches on the side of the thorax under the wing bases and black hairs around the wing bases.
Top tips for identifying carder bumblebees
These three species (Common carder, Brown-banded and Moss carder bumblebee) can be tricky to tell apart, especially when there are faded and worn individuals around at the end of the nesting season, so our top tips for spotting them are:
- Know which species might be present in your area by taking a look at our bumblebee species guide
- Learn how to safely catch and pot bumblebees for a closer look with a hand lens in our helpful video
- Practice, practice, practice! Enjoy looking out for bumblebees and spotting the differences between the species. Spring and early summer can be the best time to start identifying bumblebees before there are too many individuals around
National Insect Week is a celebration of all things insect and is organised by the Royal Entomological Society, and supported by partner organisations throughout the UK and Europe. You can find more information here.
Bees in disguise: the “black bumblebee”
Spring is here! With it comes the arrival of the “black bumblebee” – several bumblebees, cuckoo bumblebees and solitary bees that can look similar to one another and cause confusion to those spotting them. Annie Ives, Skills for Bees: Scotland Project Officer and Information Officer, tells us the differences and what to look out for.
What do you picture when you think of a bumblebee? Many people would say a large, furry insect with black and yellow stripes. But with twenty-four bumblebee species in the UK, the appearance of a bumblebee can vary hugely, particularly when it comes to colour.
Normally we identify bumblebees by first looking at their tail colour and banding. However, a few bumblebees can be entirely black. This makes them much harder to tell apart. Knowing a few helpful facts about the different black bumblebees, and the look-a-like Hairy-footed flower bee (Anthophora plumipes), can help narrow down your options. So next time a black bee buzzes past, you won’t be fooled by its disguise!
Credit: Chris Slaney
Hairy-footed flower bee
One of the most common reasons people contact us in early spring is to ask for help in identifying a “black bumblebee”. Often this turns out to not be a bumblebee at all! The Hairy-footed flower bee is a solitary bee, yet its round, furry shape means it’s easily mistaken for a bumblebee.
Most often seen between February and May, male and female Hairy-footed flower bees are small, though remain distinct from one another. The males are a pale gingery brown and have yellow faces, while the females are black all over. If you look closer, a key feature to help identify a female Hairy-footed flower bee is the orange-red hairs on her hind legs.
Did you know? Hairy-footed flower bees are active in early spring. They are especially fond of lungwort (pulmonaria) flowers. Grow some lungwort and you’re bound to attract them!
Credit: Ralph Goodson
Melanic bumblebees
Usually, the pigment in a bumblebee’s hair gives it a bright tail or yellow bands. But this is not the case for melanic (dark) bumblebees. Melanism occurs when a natural genetic mutation causes the over-production of a pigment called melanin, resulting in different colourations or ‘forms’. This causes the bumblebee to appear partially or completely dark.
Melanism is most often observed in Tree bumblebees (Bombus hypnorum) and Buff-tailed bumblebees (Bombus terrestris), but it can affect all species. This makes it very difficult to identify melanic bumblebees from their appearance alone.
Credit: Richard Dowling
Ruderal bumblebee
This late-emerging bumblebee is generally seen from May onwards and has a variety of different forms, including a melanic form. Ruderal bumblebees (Bombus ruderatus) have an exceptionally long tongue and are very fond of tubed flowers such as foxgloves. One particularly distinctive feature of this species is its large size. You should count yourself lucky if you spot one of these bulky bumblebees as they are rare and mainly found in the south and south-east of the UK, with a small number of recent records in Wales.
Credit: Nick Owens
Field cuckoo bumblebee
Being sneaky is part of the nature of cuckoo bumblebees. Much like the cuckoo bird, cuckoo bumblebees use the nest of other bumblebees (called hosts) to raise their young. In order to slip into the nest of an unsuspecting host, many cuckoo bumblebees mimic the colouration of their host species.
The most common form of the Field cuckoo bumblebee (Bombus campestris) has a yellow tail and a general yellow appearance (especially in the males). This is to mimic their preferred host, the Common carder bumblebee (Bombus pascuorum). However, there is also a melanic form of the Field cuckoo bumblebee which can appear completely black.
Top identification tip: Cuckoo bumblebees have thin, hairy back legs which never carry pollen. They often have dark, smoky wings which also helps distinguish them from the social species they mimic.
Kickstart diaries – My time with the Bumblebee Conservation Trust
31 May 2022
Over the past year, Tilly Hopkins has worked with the Trust through the Government Kickstart Scheme. Tilly has had the opportunity to gain experience working in the environmental sector and learn from passionate and skilled staff. Read Tilly’s conservation journey from creating social media content to bumblebee identification in the field.
Buzzing to begin
After losing my first role due to the pandemic in 2020, I was feeling quite lost about the next steps in my conservation career. Then the new government Kickstart Scheme came along and I was so excited to see the Bumblebee Conservation Trust was involved. After a successful interview with Trust CEO Gill Perkins and staff members Andy Benson (Senior Education Officer) and Lisa Scott (Digital and Operations Officer), I started as a Bumblebee Conservation Assistant in the Public Engagement team on the 6 May 2021 (my birthday!), with Barnaby Smith (Public Engagement Manager) as my bee-rilliant Line Manager.
I had such a warm welcome to the organisation, alongside my fellow Kickstarter’s Sinead, Kamal and Sam. The first few weeks can be a daunting time in any role, especially after being on furlough and job searching for months beforehand, but everyone was so friendly and helpful. I remember receiving a wonderful welcome pack from Gill with a hand-written note, a pack of bee-friendly wildflower seeds which I swiftly planted (they looked stunning that summer!), a White-tailed bumblebee pin badge which has lived on my rucksack ever since, and of course plenty of Trust reading material.
From desk to field
In the first half of my placement, I was home based working for the Public Engagement team. It was a really enjoyable time as I settled into my role. I got to watch lots of bumblebee and wildflower identification videos, read lots of bumblebee books, familiarised myself with the Trusts social media style and website content, learnt about the Trust in general including their values, and built working relationships within the team with Helen King (Senior Communications Officer) and Chloe Headdon (Bee the Change Officer) who were incredibly supportive. One of the highlights during this time was getting the chance to be involved in the Trusts latest online campaign, ‘Bee the Change’.
I was so excited to contribute to this brilliant project led by Chloe. The purpose being to inspire people from all backgrounds to help bumblebees thrive in their communities through simple actions that anyone can take. Whether you have a large garden or a small window box, being a part of this project opened my eyes to how all of us can help make a positive difference for these very important pollinators. I was given the opportunity to create a blog for the microsite, draft up multiple social media posts, and help to create free downloadable resources such as an autumn/winter garden maintenance guide and a children’s seed balls activity sheet.
For the remaining months, I was lucky enough to work in the Conservation team as part of the ‘Short-haired bumblebee reintroduction project’ based in Kent, led by Dr Nikki Gammans (Project manager) and supported by her trainee Clare Alley. It was an amazing opportunity to experience practical conservation work in-person and meet the dedicated group of volunteers for this project, some of which have been volunteering for the Trust for over 10 years. It was also great to meet fellow staff members face to face, and to make lovely new friendships with both Nikki and Clare.
I experienced so much variety during these months, from attending a Trust life members event, running merchandise stalls at talks, selling raffle tickets at the annual fundraising quiz, completing risk assessments for each site, arranging volunteer get-togethers, taking photos/videos for social media, attending bumblebee blitzes, carrying out BeeWalks, designing a series of seasonal churchyard signs, to habitat work parties (I’ve lost count of how many primroses and cowslips I’ve planted, but enjoyed every one!). I love driving around my local towns and villages and being able to point out to family and friends where I’ve sowed wildflower seeds, or planted seasonal forage for bumblebees. It’s even more of a thrill when you actually see a bumblebee enjoying your efforts!
Fond farewell
Like all good things my placement is now coming to an end, but it has been the most fantastic experience. I was even able to fit in attending the full team meeting held in Cheadle before leaving, which was the icing on top! I feel so lucky to have met such inspiring and motivational staff members and volunteers. Everyone is very passionate about helping bumblebee populations to flourish, and it’s not hard to understand why.
Before I started with the Trust I was interested in the natural world, but bumblebees were a new subject to me and something I was keen to learn more about – and what a learning journey it’s been! Once you start to know a little about these charismatic insects, you can’t help but become hooked. They live truly fascinating lives and I encourage everyone to take a look on the Trusts website for a better idea of their lifecycle, and the invaluable ecosystem services they provide for free.
It’s been a memorable adventure. Thank you so much Bumblebee Conservation Trust!
Bumblebees in heatwaves
The gentle buzzing of bumblebees is one of the iconic sounds of the British summer. But how will our favourite furry bees respond to the UK’s unprecedented temperatures?
Bumblebees are built for cooler climes. Unlike most insect groups, they actually prefer the milder temperatures of the temperate regions – that’s why Britain has almost 10% of the world’s bumblebee species, a much higher proportion than for most other insects. The reasons for this date back around 35 million years, to the proto-bumblebees of northern India.
At that point the Himalayas were a relatively low mountain range, with some fairly average bees. But as the Indian sub-continent pushed into Asia, the climate changed to become cooler and damper, and the bees had to adapt to survive. They already generated a lot of heat through flapping their wing muscles, but they became furrier, to keep that heat in, and rounder and larger to reduce surface area to stay warmer for longer. Eventually they became our familiar bumblebees.
But their adaptations limited their options. They were so good at remaining warm, that if they tried to fly in hot climates they couldn’t vent heat quickly enough. In trials, the American Yellow-faced bumblebee Bombus vosnesenskii started to overheat after just three minutes of flight at 42°C. The bees started trying to cool their heads by regurgitating a droplet of nectar and stirring it round with their proboscis, increasing the surface area and cooling their heads down by around 2°C. When temperatures reached around 44-45°C, the bees did this even without flying.
That temperature intolerance meant that instead of dispersing south from the Himalayas into the tropics of Northern India, they had to spread northwards, into the cooler temperate regions of Asia, Europe and North America. It’s also the reason why, in the tropics, bumblebees are generally found at high altitudes, where it’s that bit cooler.
Britain, then, was more or less ideal for the group with our mild summers. Our general lack of drought suited them too – warm and wet is good plant-growing weather, which means lots of pollen and nectar available all summer. We know that drought stresses plants, causing them to produce fewer flowers, smaller flowers, and less nectar and pollen within flowers, and that droughted flowers attract fewer bees. Hot, dry landscapes are worse for bees than warm, damp areas.
British bumblebees aren’t as temperature-tolerant as Bombus vosnesenskii. In the UK, bumblebee activity starts to drop off at around 28°C. Cuckoos and males tend to tuck themselves away in the shade and wait it out: workers keep foraging, but species gradually give up as they reach their thresholds. Buff-tailed and Red-tailed seem to be the last to go, along with some of the rarer southern species. Once temperatures reach about 32°C, virtually all outside activity ceases, though nest-fanning (workers using their wings to blow air through the nest) will continue.
Bumblebees are still able to forage on hot days – they’re out first thing in the morning and last thing at night, they just need more of a siesta in the middle of the day. But that cuts into their foraging time, and drought-hit plants are less rewarding to visit – the day’s foraging suddenly brings in a lot less food for the colony. For bumblebees that are already struggling, that isn’t great news.
Dr Richard Comont, Science Manager
Twitter @RichardComont
With the world talking climate, our science team take a look at what a changing world means for the UK bumblebees.
