Blog Post

April’s Focus on Forage

  • By mark patterson
  • 09 Apr, 2017

Mark discusses whats in bloom this month

Pink cuckoo flowers

Following a very mild March the forage this season appears to be well advanced of recent springs, even in comparison to last year’s very mild winter and warm start to the year. 2017 has started cold and chilly but in late March this has warmed up considerably. So much so that I experienced my first attempt at a swarm during the last week of March and already the new queens have emerged and unbelievably appear to have been mated and are laying in the first week of April!!!

During the first week of April many of our true heralds of spring had already begun to flower across the city. Cherry Laurel Prunus laurocerasus an evergreen shrub who’s flowers are a useful source of spring forage have been out in bloom since mid-March 2-3 weeks earlier than last year. Whilst manning the LBKA stall at Ascot race course on the 2nd April I saw many Andrena Mining bees, Honey bees, Bumble bees, Hoverflies, Queen wasps and Queen Hornet nectaring on the blooms of these tall shrubs growing around the car park.

Damson, Plum, Gage, and other stone fruits have largely flowered and gone over already as have crocus, daffodils and snow drops. My flowering currant normally just blooming now is almost over already meanwhile Blue Bells are coming into flower. 

Blue bells may be visited by Honey bees and can produce a honey crop but they are also popular with some of the longer tongued solitary bees and Garden Bumble Bee Bombus hortorum. Most of the Blue Bells found growing in our gardens and sadly in many of our wilder places are the larger invasive Spanish Blue Bell Hycinthoides hispanica and not the native English Blue Bell Hycinthoides non-scripta. You can tell the two species apart by the way that the individual bells hang on the flower stalk. In English Blue bell the bells all hang on the same side but in the Spanish Blue Bell they hang at different angles all around the stalk. They also have green to blue pollen whilst English Blue Bells have a creamy coloured Pollen. Blue Bells frequently hybridise and these offspring can be difficult to differentiate.

Hawthorn Mining Bee

In two of my local park’s pretty pink Cuckoo Flower Cardamine pratensis is forming carpets of flowers alongside Primeroses and sweet violets. This dainty little pink flower is a true sign that spring ‘proper’ has arrived. It’s an important nectar plant for many pollinators and the main food plant for the larva of the Orange Tip Butterfly – a species sadly in decline.

White and Red Dead Nettles, Dandelions, Coltsfoot, Primulas, Rosemary, Wood Anenemones, Green Alkanet, Comfrey, Lungwort, Cherry, Choiysia (mock orange), wall flowers and many varieties of apple and pear are now in full bloom and putting on spectacular shows of spring colour.  Ceanothus, Pyracantha, cotoneaster and Hawthorn are starting to bloom in some areas. This is also very early. Pyracantha and cotoneaster don’t usually bloom until late April and Early May. The Hawthorn is incredibly early. The blooms are an important source of forage for the Hawthorn Mining Bee Andrena chrysosceles.

Honey Bee on Forget-me-not

Forget-me-nots are now in full bloom and putting on dazzling displays of sky blue blooms. I often hear beekeepers who have had their honey analysed for pollen content claim that Forget-me-not pollen content is very high in their honey’s which leads them to believe that the bees have made honey predominantly from Forget-me-not forage. Whilst Honey bees certainly like Forget-me-nots I don’t think this is the case though, I just think Forget-me-not pollens get over represented due to the abundance of the pollen grains produced by the plants and their very small size not being filtered out by the bees Proventriculus.

yellow archangle

Last year in my garden I planted some Yellow Arch-angel plants given to me by a friend. These pretty foliage plants in the deadnettle family sport masses of lemon yellow flowers which Hairy Footed Flower Bees and Bumble Bee queens love. The plants have done a little too well and have covered the length of my hedge since planting last spring. They can be very invasive forming large carpets and are not suitable for planting in wild areas but perfect for under a garden hedge or shady spot where anything else might struggle to thrive. The bees are currently feasting on the blooms.

honey bee on marsh marigold

In wooded areas Lesser Celendine is forming carpets of yellow which attracts small solitary bees. This plant is unusual in the buttercup family (Ranunculaceae) as it is one of the few buttercups that is attractive to bees. Most other Ranunculus have nectar which contains the toxin protoanemonin which bees cannot digest and can lead to May poisoning. Lesser Celandine however is popular with many of our early solitary bees and occasionally Honey bees. This past few weeks I have seen many of the Micro Andrena solitary bees feeding on the golden yellow flowers. Another buttercup flower sometimes visited by bees are the Marsh Marigolds which can be found in bloom at this time of year around the margins of ponds and streams.

Honeywort

A plant which I don’t yet have in my garden but really must acquire some is Honeywort Cerinthe major 'Purpurascens. This is an attractive annual with silvery grey foliage and pendular bell shaped flowers in purple hues. It is much loved by bees.

Ashy Mining Bee on Willow catkins

Other important sources of forage this month are the willows. Many of the willows I’ve seen have already been and gone but some continue to sport fluffy catkins bearing copious amounts of sulphur yellow pollen. If your honey bees are returning to the hive dusted in yellow they will most likely have been visiting willow. It’s not just honey bees that visit willow. Many bumble bees and Andrena bees will also collect willow pollen. Unlike the earlier flowering Catkins of Alder and Hazel willow will also produce nectar.

Other trees coming into bloom right now include Field Maple, Sycamour, Poplar and Ash (a species which scientists have recently predicted will likely become extinct within our life time due to Ash Die back disease and the invasive Emerald Bark beetle).

box honeysuckle

On the 3rd of April I saw my first Horse Chestnut blossom of the year outside Bow Road Tube station. This is very early indeed and we should be ready for a strong spring nectar flow if the warm weather continues. Chestnut produces very distinctive dark brick red pollen which honey bees will collect with enthusiasm. Chestnuts are one of the best examples of how plants communicate with their pollinators; the individual blooms of the flower stalk or inflorescence change colour as they are fertilised to inform the bees that they need not bother to visit that particular bloom. When they come out in flower watch them and look out for the change in colour.

Also in bloom are the Cherries, before mentioned Apple, pear and Hawthorn. Another shrub in bloom this month which is attractive to bees but unfortunately seldom gets a chance to bloom because it gets clipped so frequently is box honeysuckle. This shrub flowers in April and is highly attractive to bees if not trimmed to within an inch of its life.

Canary Bird Rose

I am not a particularly big fan of roses. Most of the garden types are too showy for my liking and useless for pollinators. I also find they get plagued by aphids, moulds, mildew and rust and I dislike the thorns. I make an exception for the wild Dog Rose Rosa canina and Rosa rugosa which bees loves. My favourite rose is Rosa x zanthina ‘Canary Bird’ which has beautiful single canary yellow flowers. All manner of bees love this rose and in my local park a group of them are just coming into bloom. When the sun hits the bush in the afternoon is gets covered in solitary bees, bumble bees, honey bees and hoverflies. If you have room for a rose in your garden I would highly recommend it.

Rosemary

Later this Month Laburnum should begin to flower. This is a leguminous tree with drapes of yellow pea like flowers. Toxic to humans but apparently safe for pollinating insects this small attractive tree is a magnet for bees.

In rural areas Oil Seed Rape is now coming into bloom and will blanket vast areas of the countryside in swathes of yellow well into mid-May. During a visit to the Yorkshire Beekeeping Association Spring Convention on the 26th March I passed many fields sporting a patchwork of yellow as the crop was coming into flower. Rape is one of the most frequently grown crops in the UK and the source of much of our vegetable oil for cooking as well as oil for cosmetics and biofuel. Beekeepers either love it or hate it for it can produce an abundance of honey but the grainy texture and trend to crystallise rock hard in the comb are a drawbacks. Beekeepers wishing to make a rape honey crop need to supplementary feed their bees from mid-February onwards to ensure spring build up and a strong colony is established in time for the crop flowering. Beekeepers in areas with rape not wanting the hassle of dealing with a quick to crystallise honey can use the rape flow to build up their colonies ready for the main summer flow later on.

 

All this early forage means colonies are building up fast and weekly inspections of our bee hives will be necessary from now until high summer if we want to catch a colony intending to swarm before the bees leave. Already some of my hives have 3 supers above a queen excluder. Already these supers are filling up with honey and with luck I may get a good spring crop this year.

Our Nando's bees sporting 3 supers already
By mark patterson 19 Mar, 2023

If you had asked me this question 5 or 6 years ago my answer based on available published materials would have been a ‘yes’ but… wild bees have a variety of physiological and behavioural adaptations that allow them to compete successfully with other insects and in a healthy environment with diverse and abundant flora, the scale of competition is probably not that severe unless there’s an awful lot of hives in the vicinity. I would have also said that the mechanisms by which competition occurs are also not that well understood and more research is needed. My answer was a cautious yes.

Ask me the same question in 2023 and I’m going to say ‘Yes without a doubt and the competition is real.’

Whats changed my opinion?                        

Prior to 2017 the published evidence available for Honey Bees posing serious competition to wild bees was limited and is summed up in a 2017 review of 147 available studies (see here: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0189268 ). This review concluded that the evidence was inconclusive with highly variable results. 53% of studies reviewed showed that Honey Bees had a negative impact on Wild Bees, 28% showed no impact, others showed the opposite. Not all of these studies looked at resource competition specifically but within those that did the degree or severity of competition varied. At this time the mechanisms of competition were poorly understood and the evidence for population levels of impact was largely absent. Few if any of these studies were able to link causality with a negative correlation.

Since then there has been a wealth of new studies published which demonstrate concerning levels of competition between Honey Bees and Wild Bees. This growing body of evidence has broadened understanding of the competition mechanisms and how exactly Honey Bees can impact Wild Bees. Many of these studies have gone on to quantify the levels of impact and have demonstrated that competition from Honey Bees can have population level effects on wild bees.

Managed Honey Bees are ravenously hungry organisms

We need to clarify that when we talk about Honey Bee competition we are referring to managed hive bees, not wild honey bees nesting in a tree cavity. Researcher Torben Schiffer from University of Wurzberg who recently gave a lecture on the subject makes some interesting comparisons which I’ll describe below.

A wild native Dark European Honey Bee Apis meliffera meliffera is a frugal and efficient organism. Their tree cavity domiciles are thermally efficient, they are frugal with food stores and their impact on the environment is minimal. They can survive winter into spring on as little as 9 pounds of Honey stores. It’s generally recommended that hived bees require 30-40 pounds of honey stores to survive winter and even then many beekeepers have to feed fondant. A wild native type colony will consume 0.2%- 0.4% of the floral resources within a 1km radius of the hive leaving 99.6 % of the floral resources for other pollinators.

Managed Honey Bees are a totally different animal. Firstly in the last 150 years we’ve forced them to live in cavernous square boxes made largely from thin wood and since Varroa we’ve given them open mesh floors making them draughtier. These wooden hives are great for preventing the urge to swarm and making excessive amounts of honey but the poorly insulated houses causes the bees to consume far more resources to maintain the atmosphere inside their nest. The bees are also compelled to fill the large volume boxes with honey and this leads them to consume more resources than the native ecotype bees living in their natural tree cavities. We’ve also changed the genetics of the bees we keep for honey production by importing and cross breeding with other subspecies from warmer climates. This results in hybrid vigour and colonies which make a bigger and more profitable honey crop but consuming more resources in the process. When selecting lines to breed from Beekeepers overwhelmingly select for larger colonies which produce more honey. A modern Managed colony in a large hive box or even a national double brood box set up will consume up to 20 times the floral resources of a native ecotype colony residing in a tree cavity. Each managed colony consumes between 2.6% - 4.5% of the floral resources within 1km radius of the hive. 22 colonies per km2 in an intensive landscape would consume 99% of the floral resources leaving little for other pollinators.

In nature or even in the old days of keeping native honey bees in straw skeps the impact of a dozen colonies per km2 was the equivalent of one large modern colony. Add to this that we have far fewer floral resources than we did 100 years ago and its very easy to see how large numbers of modern managed Honey Bee hives can swallow up available floral resources making life challenging for wild bees.

Competition mechanisms

Recent studies have shed light on the mechanisms of honey bee competition and how it effects wild bees.

When Honey Bees forage they spill out of the hive and disperse across the landscape in search of floral resources. At first they will exhaust the forage nearest the hive before dispersing further outwards. When this is depleted they will disperse further out again, and again and again and can easily reach a 3km radius of the hive in summer. They can forage as far afield as 12 km according to research by University of Sussex. As they disperse outwards they create a halo effect around the hive/apiary. Nearer the apiary floral resources are depleted quicker and visited more regularly so they are repeatedly depleted as the plants recharge the nectar supply. Further away from the hive the visitation rates or density of foragers visiting flowers tends to reduce.

Numerous studies have shown that within the halo area of a hive or apiary flowers contain fewer pollen grains than those on the same types of flowers further away from the hives. It’s also been shown that these plants nearer the hives contain less nectar because they get visited by the honey bees more frequently. So even if you’re a long tongued bee with physiological adaptations evolved to be better adapted to a particular bloom the sheer number of Honey Bees visiting a patch of flowers can deplete the nectar you’re competing for.

Numerous recent studies have demonstrated that within the halo area of a hive/apiary the abundance of wild bees is reduced. Two studies published autumn 2019 studying bees in urban Paris and in southern France both reported that wild bee abundance was halved within 600 meter radius (halo area) of honey bee apiaries and that larger apiaries resulted in the same effect but over a larger halo/radius. The southern France study also demonstrated that the foraging success of wild bees was halved in proximity to honey bee apiaries which lead to a decrease in reproductive success and a gradual decline in species abundance over successive years. This study was one of the first to successfully link causality with correlation something many previous studies had failed to demonstrate. The study found that pollen and nectar was substantially reduced within the halo area of the apiary and that wild bee foraging success was significantly reduced, fewer nests were provisioned and this resulted in a reduction in the population the following year. It’s worth noting that the study also found that within the halo area Honey Bees foraging success was also reduced which highlights competition between hives and raises welfare concerns.

It’s worth noting that the southern France study was undertaken in pristine rural florally rich habitat where there was a seasonal super  abundance of forage, yet despite the healthy environment the presence of 15-30 Honey Bee hives per km2 had a significant impact on wild bee survival and reproductive success. This makes me question my previous thoughts that ‘in florally diverse and abundant environment the scale of competition is probably not that severe.’

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0222316

https://www.nature.com/articles/s41598-018-27591-y

A research paper published February 2020 in the royal society has highlighted that the huge increase in honey bees in the Mediterranean basin is reducing wild bee abundance and diversity and is contributing to wild bee declines, exaggerating declines caused by climate chance and habitat loss. https://royalsocietypublishing.org/doi/10.1098/rspb.2019.2657

Numerous studies have demonstrated that Honey Bees have a negative impact on native pollinators where Honey Bees have established outside of their native range. Most of these Studies come from North America and Australia and suggest that where Honey Bees are not native they have a bigger competitive impact on native bees. See works of kit Prendergast. https://www.researchgate.net/profile/Kit-Prendergast

Honey Bee communication gives them a competitive advantage over wild bees.

Different Bee species range greatly in size from just a 2 millimetres in length ( Perdita minima ) to 2.5 inches in length (Wallace’s Giant Leafcutter Megachile pluto ). It’s been well documented and understood for many years that larger bodied bees are capable of flying greater distances to forage than those of smaller species. There are various matrices that allow for the calculation of bee foraging distance from the nest based on body size and wing morphology. https://www.researchgate.net/publication/6347364_Bee_foraging_ranges_and_their_relationship_to_body_size

So for example a small bee like the 7mm long Chelostoma campanularum or Bellflower Scissor Bee only flies to forage within a radius of around 50 meters from its nest site whilst a large Bumblebee is capable of foraging well over 2.8 kilometres from its nest. Some experimental studies have shown that when solitary bees are forced to fly further afield to forage the resulting energy and time expenditure results in a significant decrease in brood being provisioned and therefore reproductive success. Breeding success can be reduced by a third https://jhr.pensoft.net/article/51182/. So if your a small solitary bee and your forced to fly further afield to forage because a beekeeper placed a Honey Bee hive  close to your nest and those bees are going to deplete the food within a few hundred meters radius of your nest your basically screwed.

Several studies have demonstrated that the Honey Bees highly social structure and advanced communication abilities give them a big advantage over other Bees. Communication allows Honey Bees to share information on forage location, abundance and quality with their nest mates and then exploit a floral resource until it’s depleted.

A 2022 study demonstrated that sociality enables Honey Bees to fly much further than other bees of a similar size or even larger than they are. The ability to share information on food resources is thought to cause increased exploitation competition near the hive/apiary due to foraging nest mates competing with one another, which in turn promotes foraging at greater distances as the bees attempt to avoid a “halo” of low food availability in the vicinity of the nest.

The researchers also noted that colony size reflected the range at which the colonies foragers travelled. Larger colonies foraged further from the nest than smaller colonies and Honey bee colonies also foraged much further afield in food limited environments and or to exploit particularly rewarding forage sources. The fact that smaller solitary bees forage at significantly shorter distances than Honey Bees means they are particularly vulnerable to competition from Honey bees and habitat fragmentation, possibly more so if they are a monolectic or narrowly oligiolectic species.. https://www.sciencedirect.com/science/article/pii/S0960982222017122

These revelations go a long way to understanding the mechanics of competition between Honey Bees and wild bees and backs up findings from previous published works.

If we look at the recent French studies which demonstrated 50% reduction in wild bees in proximity to managed apiaries and we apply what we now know about Honey Bee foraging tactics it becomes easy to appreciate how lots of hives in any given area, no matter how florally abundant can result in negative impacts on wild bees.

Over hiving of Honey Bees in Cities

Several recent studies have highlighted how the explosion in urban beekeeping in European cities is quickly becoming unsustainable with numbers of hives outstripping the available forage and having potentially serious impacts on wild bees.

Evidence from Brussels, several Swiss cities, London and Berlin show there are more hives than the habitat can support. A Berlin study appeared to show that high Honey Bee abundance reduced the number of wild bees. https://link.springer.com/article/10.1007/s00442-021-04862-6 and Bee conservationists are deeply concerned by the 16 hives perkm2 average  present in Berlin in summer as migratory beekeepers move colonies into the city to take advantage of the Linden bloom.

Phil Stephenson’s 2019 paper established that the landscape carrying capacity of European cities like London is 7.5 hives per km2 and demonstrated that parts of Greater London far exceed this, demonstrating how unsustainable urban beekeeping has become in the capital. https://nph.onlinelibrary.wiley.com/doi/10.1002/ppp3.10143. According to the National Bee Unit data there is one area of London with almost 400 hives per km2 and several areas close to the city centre exceeding 50 hives per km2!  https://drive.google.com/file/d/1-Y3XCP50RCDy_9jq_oCB8VI6FOQtUns9/view

The before mentioned Paris study found wild bee abundance was reduced by half within 600m radius of urban apiaries.

A 2022 study revealed increases in hives numbers across Swiss cities from an average 6.48 hives per km2 in 2012 to an average 8.1 hives per km2 in 2018 and observed that available resources are insufficient to maintain present densities of beehives, which currently are unsustainable. https://www.nature.com/articles/s42949-021-00046-6

A 2022 review of recent research looking at Honey Bee competition on wild bees summarised that 'the Literature supports significant evidence for competition from managed bees.'

https://www.sciencedirect.com/science/article/pii/S2666515822000154#:~:text=Introduced%20bees%20(predominantly%20honey%20bees,set%20of%20invasive%20plant%20species.

A February 2023 published study from Montreal Canada demonstrated that a 10 fold increase in Honey Bee hive numbers between 2013 and 2020 resulted in significant depletion in pollen availability in the cities Clover crop and a significant decline in wild bee abundance echoing studies in European cities. https://peerj.com/articles/14699/

 

My conclusions

Having studied the findings of recent research on the subject and heard explanations from a number of experts (some of whom carried out the work) I’m now convinced that managed Honey Bees are contributing to wild bee declines.

This is a tough pill to swallow for beekeepers particularly commercial bee farmers who rely on placing large numbers of hives in florally abundant areas to make a honey crop amidst a hostile commercial market undermined by cheap foreign imports and adulterated product.

Many Beekeepers question the evidence pointing out that prior to 1900 there were significantly more hives than today and that most of the studies were conducted abroad.

Firstly the managed bees we keep today are a completely different animal than those we kept 100+ years ago and as pointed out earlier are larger, consume more resources and have an impact up to 20 times greater than the native wild Honey Bee kept in days gone by. Secondly we’ve lost 98% of the flower rich meadows and half of our hedgerows since the 1950s. The UK sits in the bottom 10% of most biodiversity/nature  depraved nations in the world and is ranked least biodiverse nation in the G8. Studies conducted in continental Europe where floral resources are far more abundant than in the UK demonstrated serious levels of competition and impact on wild bees. If these studies demonstrated concerning levels of harm in environments healthier than the UK then its reasonable to assume the impacts here are just if not more serious. Note that in the Study by Gruter et all referenced earlier it was stated that the evidence was that Honey Bees foraged further afield and applied greater competitive pressure on wild bees in environments which were food limited.

Many beekeepers do not have an academic or science background and find the published works difficult to read and understand. Many simply state they don’t make sense and refute them. There’s a need for improvement in how we convey these findings in laymen’s terms particularly to hobbyist beekeepers so they can understand the importance of such research and its implications for beekeeping.

 It’s not the Honey Bees fault we are in the situation were in, and we must not 'bash' Honey Bees,  it’s a manmade problem. We’ve changed the landscape, reduced the floral resources, meddled with the Bees biology, morphology and behaviours through breeding programs and forced them to live in thermally inefficient resource costly manmade boxes.

 

What can beekeepers do to reduce their impact on wild bees?

·        Keep fewer colonies. The threshold for impact being noticed is 3.5 managed colonies per km2.

·        Keep smaller colonies. Smaller colonies create less competition and consume fewer resources.

·        Keep native eco-type bees, don’t import foreign strains.

·        House your bees in more thermally efficient hives by either cladding wooden hives in cork or using poly hives which are 76% more thermally efficient.

·        Ditch open mesh floors. Draughty hives increase resource consumption.

·        Don’t place apiaries within 2.2 km of nature reserves and areas of importance for wild pollinators.

·        Keep your bees healthy to avoid pathogen spill over which is an additional problem to floral resource competition.

 

What are apicultral doing to mitigate impact our own beekeeping activity has on wild pollinators?

When pointing out research demonstrating Managed Honey Bee impacts on wild pollinators I’ve been repeatedly called out for being hypocritical and ‘holier than thou.’ I’ve been especially critical of companies pumping more and more managed hives into inner London where its quickly become ridiculously unsustainable to keep the number of bees present and calling out beewash.

Firstly, we’ve never introduced hives to inner London resulting in a net increase in hive numbers. Most of the hives we manage have been placed there by other beekeepers on behalf of clients, often more than a decade ago and we’re simply the current apiary managing contractor. Whenever we take over an apiary the first thing we do is reduce the number of bee hives down to just 2 in an attempt to reduce our impact at that location. Since 2016 we’ve reduced the number of hives we manage by almost two thirds. in 2022 we reduced the number of hives in the City of London by 3 and were removing a further 2 hives in March 2023. In the last few years I've convinced 5 clients to give up keeping bees because I felt it was not worth while or in the best interests of the bees welfare.

When we have introduced bees to a new client (We've only done this 3 times in 10 years) we have not brought bees in from outside the area adding to a net hive increase. We’ve only ever redeployed hives and the redeployment has been kept to within the same neighbourhood.

We keep our inner London colonies small. We don’t use double brood box set ups or over stimulate colonies to be big to maximise the honey crop. We go out of our way to explain to the clients why their bees are not as productive and that its to minimise competitive stresses to wild bees.

Most of our bees are kept in poly hives which are thermally superior to wooden hives, the bees are healthier, and survive on fewer resources. Some of our hives like Mansion House and Selfridges are poly hives inside wooden protective lifts which are even better still.

We’re delivering significant habitat investments for clients and delivering in depth wild pollinators surveys to monitor our impact and promote wild bee conservation over Honey Bees.

By mark patterson 10 Apr, 2020

Like many beekeepers up and down the country I was excited to receive my National Honey Monitoring Scheme results in Late March.

The national scheme run by the Centre for Ecology and Hydrology is a citizen science project which aims to find out which species of flowering plant are most important for honey bee nutrition in the UK. The scientists behind the scheme hope to use the results of their study to make informed decisions on future rewilding projects to benefit honey bees.

I have always been sceptical of the accuracy of pollen analysis from honey samples as a means of finding out what plants are important for bees. There are many caveats and flaws involved and I was keen to see what the results from my samples would reveal.

The CEH national Honey Monitoring scheme relies on DNA analysis to provide identification of species contained within the sample and to estimate the volume of material from each species found. The DNA found in the sample is compared to a digital database of already sequenced material.   This differs from conventional methodologies which rely on identification and counting using microscopes. This method is quicker and less laborious to perform but the results are often not accurate.

Some issues with reliance on this type of analysis

  •  Firstly the results of any analysis will rely on what is locally available for bees to feed on and that can differ widely from one location to another. Often it’s the case that honey bees will make the best use of what’s growing in abundance around them rather than what is best for them.
  • Summer honey samples often omit the important early season forage which is used up by the spring brood nest or lost following shook swarms of the colony and the old combs discarded. This means forage sources important to bees early in the season may be omitted or under represented.
  • Some plants are frequently over represented in honey samples because their pollen grains are very small and are less efficiently removed from the nectar by the bees proventriculus – an organ at the junction of the honey crop and digestive stomach which filters pollen grains from the nectar in the crop. Bees are highly efficient at removing pollen grains from nectar in the region of 30,000 fold reduction in pollen grains. Therefore plants with smaller pollen grains are often over represented in samples while larger grained species are filtered out and underrepresented. Furthermore plants don’t produce pollen grains in equal abundance, some produce very few grains per flower whilst others produce many so the numbers of these pollens present (absolute pollen concentration APC) is a poor indicator of the nectar contribution from that flower towards the honey crop produced. Scientists can factor these caveats into their analysis of honey by applying a pollen coefficient value (PCV) which compensates for over or under representation of pollen grains in the honey to provide a more realistic interpretation of the results. Habitat type, species composition and abundance in the local environment is needed to formulate PCV for different locations.
  • DNA barcoding techniques used to decipher the species contained within a sample rely on the comparison to an existing data base of already sequenced species. Species identification is assigned to pollen grains contained within the sample based on similarities to the existing data base. Closely related species, hybrids or regional variance in genetics can confuse the analysis. Species not yet sequenced and held in the catalogue can also not be correctly identified. At best these species may be assigned to genus or taxanomic family level.

  • Not all bees use the same species of flower to the same degree as honey bees may do so using this sort of analysis to inform rewilding schemes will not benefit many wild bee species which are in decline and need prioritising for conservation measures. Honey bees are not a conservation priority species not being threatened, endangered or in decline in the UK nor globally.

So far I have received results from 2 out of the 4 samples submitted. One is from the City of London and contained 71 species. The other was from the Olympic park and contained 47 species which is far less than I would have expected.

Of my City of London Sample I was surprised that Turnip Brassica rapa was the most abundant pollen. The very centre of the city has few extensive vegetable plots where my bees could find so much Turnip Pollen. In fact 3 of the top 5 species found in the sample were Brassicas or cabbage family members including Rape and Cabbage. It’s possible these inclusions are subject to misidentification of similar and closely related species such as Wild Raddish, Wild Field Mustard, Bitter Cress, Rocket and other crucifers which are frequently found on city centre green roofs. All these species are also known to have inflated pollen representation which will skew the results. Brassicas and Crucifer plants readily hybridise, have been selectively bred into many varieties and frequently cause problems for those who study their pollen grains.

Bramble was second most abundant pollen found in the city centre sample and a kilometre or more from the apiary there are significant amounts of bramble along over ground railway sidings so this is not so surprising.

I was pleased to see many species which I have planted on a nearby 3500m2 biodiverse green roof represented in the honey sample. Species include round headed onion Allium spharocephalon, Wild Carrot Daucus carota, Echium’s (though not the species listed in the results which I think must be confusion over the exact species). Also listed was Broad Bean Vicia faba. Whilst there are several small patches of broad beans on rooftop gardens in the city centre there are also many other vicia species which frequently occur in abundance on green roofs. These include hairy Tare, Tufted Vetch and Common Vetch. Furthermore Honey bees have short tongues and often steal nectar from Broad Beans by biting a hole in the base of the flower bypassing the organs releasing the pollen. It’s possible that Broadbean is another misidentification. One species present did baffle me. Allium ursinum the Wild Garlic. In London this plant blooms in Late march through to April and the colony the honey sample came from was shook swarmed onto undrawn foundation in Early May so I can’t see how this species could be present in the honey sample submitted. The nearest substantial area of this plant is Tower Hamlets Cemetery Park almost 1 mile away. I’m assuming that this was an error in identification.

By mark patterson 30 Mar, 2020

There has recently been a number of research papers published highlighting undeniable evidence that the exponential worldwide increases in managed honey bee hive numbers is having a detrimental effect on wild bees and on plant communities.

Contrary to popular believe honey bees are not threatened any where on Earth, they are not in decline and are considered by the International Union for Nature Conservation (IUCN) as being of ‘least concern.’ The UN’s Intergovernmental Panel on Biodiversity and Ecosystems services (IPBES) reports that globally numbers of managed honey bees are increasing with a current estimate of 81 million managed bee hives ( https://ipbes.net). Despite high seasonal losses in some regions of the world few areas are experiencing actual declines and globally the picture is one of exponential increases. This increase is being driven by a growing human population, requiring higher agricultural outputs and increased demand for pollination services (Breeze et al 2014).

In the UK hive numbers have recovered quickly following declines at the turn of the 20th century and post world war eras. The National hive count reported by DEFRA to the EU hive census is around the 247,000 colonies number (National Bee Unit 2019). In the UK urban areas are where the largest increases in hive numbers are being noticed. In Greater London hive numbers have more than tripled in the past decade to around 7000 colonies (DEFRA 2019). Parts of the city now host 40 or more hives per km2. The science suggests that landscapes rich in flowers could support 12 colonies per km2 (Ratnieks 2014, the biologist) so in parts of London it appears that hive numbers are exceeding the carrying capacity of the landscape by a large magnitude as most of the city has less than 2 ha of good bee foraging habitat per km2 (2009 London borough green space survey data held by Green Space Information for Greater London).

Many ‘save the bees’ messages being circulated by well meaning but misguided campaigns continue to focus on honey bees which are not in any danger and are not well aimed at the bees really at risk which are wild bees, the bumblebees and solitary bees. Wild bees have recently been proven to perform the bulk of commercial crop pollination and current best estimates are that overall honey bees are only responsible for 30% of insect dependant crop pollination in the UK. There are also individuals and organisations with financial interests in honey bees who whilst aware of the situation perpetuate honey bees in danger messages and encourage more urban hives for their financial gain.

The decline in wild bees has serious implications for agriculture and ecosystems services.

Previous papers published before 2017 had concluded that evidence for honey bees outcompeting wild bees were inconclusive and showed mixed and highly variable results. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0189268

Opinions among the scientific community are however now shifting based on new evidence being made available.

Two studies published autumn 2019 studying bees in urban Paris and in southern France both reported that wild bee abundance was halved within 600 meter radius of honey bee apiaries and that larger apiaries resulted in a worse effect. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0222316

It’s worth noting that in the Paris study honey bee apiary and hive density was no where near as high as London or cities like Berlin and Brussels which have very high honey bee densities.

Studies have shown that wild bees often fair better in urban landscapes where more diverse plant communities which includes exotic plantings can support a wider variety of bees but bee abundance is ultimately dependant upon floral resources - which can be limited. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0225852

The southern France study also demonstrated that the foraging success of wild bees was halved in proximity to honey bee apiaries which lead to a decrease in reproductive success and a gradual decline in species abundance. https://www.nature.com/articles/s41598-018-27591-y

A research paper published February 2020 in the royal society has highlighted that the huge increase in honey bees in the Mediterranean basin is reducing wild bee abundance and diversity and is contributing to wild bee declines, exaggerating declines caused by climate chance and habitat loss. https://royalsocietypublishing.org/doi/10.1098/rspb.2019.2657

Several papers published recently have highlighted the role of anthropomorphic honey bee disease, pest and pathogen spread on wild bee populations with some wild bee species being driven to the knife edge of extinction. Imports of honey bee queens and packages from Southern Europe, New Zealand and Argentina continue to grow year on year to meet the increasing demand for bees mostly from new hobbyist beekeepers. In 2019 more than 19,000 queens and 2400 packages of bees were imported to the UK from continental Europe (National bee unit SE region report February 2020). Each year the UK also imports thousands of packages of bumblebees from Turkey and Belgium. Research has shown that as many as 70% of these bumblebee packages harbour 3 or more honey bee pathogens known to be spreading to wild bees (Dave Goulson, Sussex university).

One study reported that instances of honey bee diseases found on flowers was high within several hundred meter radius of honey bee apiaries and that there was potential for this to be a vector for honey bee virus transmission to wild bees.

A paper by Dave Goulson 2 years ago warned about the increasing instances of honey bee pathogen spread to wild bees and recommended measures across economic regions to prevent further impact on wild pollinators. https://www.sussex.ac.uk/webteam/gateway/file.php?name=goulson-hughes-15-review-mitigating-anthropog...

Finally several papers published recently have highlighted that honey bees often favour ornamental and non native species of plant when foraging or favour a small group of native plants over others. Various papers have shown that over time honey bees are effecting landscape level changes in plant diversity to meet their foraging preferences which is effecting the survivability of plants and their co-dependant pollinators. https://www.nature.com/articles/s41598-019-41271-5

In London and other large cities we are seldom any further than 500 meters from another beekeepers apiary and in many instances much closer. We all need to be mindful of the impacts our beekeeping has on the wider environment and wild pollinators. high density urban beekeeping is likely having an adverse effect on declining and struggling wild bee populations.

some European cities are now restricting establishment of further urban apiaries to conserve wild bees.

Urban environments are becoming increasingly important for sustaining populations of wild bees which are suffering catastrophic declines in rural areas. For example in London Borough of Tower Hamlets and LB Newham urban areas are supporting the only inland populations of the black mining bee found in the UK, and many London parks support rare brown banded carder bee and red girdled mining bee - a nationally scarce species. London also hosts several species of bee found nowhere else in the UK including Hoplitis adjuncta the vipers bugloss mason bee and hawks beard Nomad bee.

In short keeping honey bees does not help the environment or improve biodiversity. Suggesting it does so is #BeeWash and counter productive to conservation efforts.

Should we be keeping bees then?

There are of course plenty of good and justified reasons for urban beekeeping. It’s a convenient window into the word of insects and makes a great education tool, can be used as a form of therapy with people suffering mental health complications and learning difficulties and it’s also a fun and enjoyable hobby. For many beekeeping is as much a social activity and an outlet to meet and mingle with like minded people through a beekeeping club or association.

If businesses such as hotels and restaurants want to have their own in house honey on their menus then that’s perfectly legitimate too. But businesses going down this line of thinking need to be aware of the bees needs, welfare and the impact their hives may have on the wider environment. It may be a better option to support a small local producer on the edge of the city where the habitat is better, honey yields are higher and to promote your businesses actions supporting a small artisan producer through sponsored hives.

What we do need to curb though is the trend for businesses to plonk bees on city roof tops without giving thought to the wider environmental issues and using a hive as a green tick box exercise claiming they are saving the environment when they are not. Unless your business is involved with structured research with a conservation outcome, investing meaningful sums of money in planting for bees or making efforts to educate and raise awareness among staff, clients and your supply chain then hosting a hive of bees on its own has no positive environmental benefit.

How can you reduce your beekeeping activities impact on wild bees.

1) Plant for pollinators. Bees and flowers go together. Especially helpful is to plant flowers wild bees prefer and not just plants honey bees favour. This could be flower pots on your buildings windows, a biodiversity green roof if you don’t have a ground level garden. Businesses could sponsor planting projects in the public realm where local authority budgets have been cut.

2) Plant for seasonal continuity with a variety of flowers in bloom throughout the year.

3) Include solitary bee nesting habitats in your gardens. These could be dry aggregate soil mounds, nest boxes containing tubes or dead wood habitats. Only honey bees nest inside bee hives, wild bees need these other sorts of nest sites to breed and hibernate.

4) Practice exemplary good apiary hygiene which reduces disease risk spread to wild bees. Keep bits of wax, honey and hive products sealed and out of reach of robbing bees. Regularly clean equipment including scorching of hive bodies. Dispose of beekeeping waste efficiently.

5) Keep small apiaries. Saturating urban areas with many hives literally takes food out of the mouths of wild bees.

6) Avoid imported bees which can bring in novel pathogens lethal to our native bees as well as being more productive than locally adapted bees which means they consume more floral resources and are more likely to rob neighbouring colonies or apiaries.

By mark patterson 30 Mar, 2020

Most of the world is in lockdown. Millions are working from homer, Millions more have lost their jobs as whole industries shut down and everyday human life grinds to a halt. The streets and roads are deserted as a deadly disease ravages the human population world wide…. No this is not an apocalyptic sci-fi movie this is real life present day Planet Earth.

A few weeks or months ago no-one could have foreseen the circumstances which we currently find ourselves in. It’s a humbling reminder of how fragile life can be.

Whilst human life is slowed down and most of the population is locked down following stay at home orders, life for bees and other wildlife continues on as normal.

Its late march and on warm days an increasing variety of bees are venturing outside from their underground burrows, nesting tubes and wall cavities to continue their annual cycle of finding a mate, building a nest and continuing the species. Hairy footed flower bees hurriedly fly about our parks and gardens collecting pollen from Comfrey and Pulmonaria flowers, Bumblebee queens flit between patches of white Deadnettle, Flowering shrubs and Spring flowering bulbs. Bee flies whiz back and forth among primeroses and the earth moves as Chocolate Mining bees emerge from beneath the ground.

With most of the worlds Human population in lockdown the Earth once again belongs to the wildlife around us. Road verges, parks and playgrounds go unmaintained, the grass growing longer than usual without it’s regularly mow allows wild flowers like Dandelions, Lawn Daisy and Speedwell to prosper. These are food for many bees but particularly lawn specialists like Andrena labiata the Red Girdled Mining Bee. I’ve noticed this nationally scarce species more and more frequently in London’s open spaces in recent years as austerity and council budget cuts have meant more areas of lawn are left longer between cuts. This is an example of a species who might just benefit from the current Corona Virus lockdown as it benefits from reduced lawn interventions.

By mark patterson 29 Oct, 2019

Beware of spooky flesh eating zom-bees this Halloween

It’s well known that bees are vegetarian and get all their protein from plants in the form of pollen right…..? Wrong! There’s a little known group of more sinister sounding bees that feed on decaying flesh and Halloween is the perfect time to learn about them.

Vulture Bees are a group of bees belonging to the Trigona genus found in Central and Southern America from Panema, The Amazon basin to Guiana. The Trigona genus comprises of about 80 species, all of which are social bees nesting in small colonies and producing modest stores of honey. They are often referred to as stingless bees along with Melopinini bees since they don’t sting in defence of the colony like other bees do and instead they bite aggressors to defend their colony. They build neat little nests in tree hollows and hollow branches using wax and plant resins. Their nests are a series of disks with the hexagonal honey pots arranged on the upper side of the disk – sort of like a wasps nest but upside down.

Of the 80 or so Trigona bees, 3 of them are referred to as vulture bees because of their unusual habit of scavenging dead carcasses for protein. They are what entomologists refer to as obligate necrophages meaning they must feed on flesh for protein. These tiny bees lack a pollen carrying brush on their legs like other bees in their family and do not store pollen in their nests. Whilst they still visit flowers to collect nectar from which to make honey andi n the process still pollinate plants, they do not collect pollen and instead feed on decaying flesh as their sole source of protein.

Until recently little was known about Vulture bees. One of the 3 species Trigona necrophaga was only discovered in 1982 and its only more recently that they have been properly studied to understand exactly how they live.

The bees home in on decaying carcasses with their keen sense of smell and are probably also able to detect the thermal signature of warm decaying bodies. When they find a suitable corpse to feed on they need to find a way into the flesh. They are small bees and not capable of chewing through thick animal skin to get to the flesh so like flies they rely on entering the body through open wounds or natural openings like the nose, eyes sockets, ears and mouth.

They chew on the soft decaying flesh and store it in an adapted honey stomach until they return to the nest where they regurgitate the rotting flesh which is fed to the bees larva. These bees add enzymes to the flesh to prevent it decaying completely and will make a bee bread like substance from the flesh for longer storage.

Unlike the Honey Bee which performs a complex waggle dance to communicate to their nest mates where they have found good sources of food the Vulture bees are thought to communicate using pheremone trails and trails of saliva - so dont expect to see these bees dancing to Michael Jacksons Thriller any time soon - though if they did it would look pretty cool.

So who’s dressing up as a Vulture bee this Halloween?

By mark patterson 08 Sep, 2019

Varroa destructor is an external parasite of the Western Honey Bee Apis mellifera  which originated in Asia on the closely related Apis cera. Whilst Apis cera has naturally occurring adaptations to allow it to cope with Varroa, the mites presence in Western Honey bee colonies is detrimental given that the Western Honey Bee has a longer sealed brood period which enables the mites to reproduce on their hosts at a faster rate.

Varroa is now endemic throughout Western Honey bee colonies and is found in almost every apiary in Europe and North America. If left unmanaged infestations can cripple a colony in less than a season.

How they reproduce

Mature mites live on the bodies of adult Honey bees where they wedge themselves between the plates on the underside of the bees body and feed on the bees Fat Body. The fat body are a series of organs which are important in the bees immune system regulation, nutrient storage and act as the bees liver removing toxins. They are found in clusters on the roof and floor of the abdomen. In order to breed gravid mites with mature eggs inside their bodies enter the bee’s brood cells just before a larva is due to be capped and hide beneath the larva. The mites are sensitive to the bee’s pheromones in the hive and can tell by the larva’s smell that it will soon be capped. Once sealed inside with the pupating larva they then begin to feed on the developing pupa. After 3 days inside the cell feeding the mite then begins laying eggs on the Pupa at 30 hour intervals. The mite may lay 5-6 eggs on the larva but depending upon whether the mite is in a drone cell or worker cell she can only raise 1-3 daughters at a time due to the length of time they take to mature and the duration of the pupa’s transformation. The first egg to be laid and hatch is always a male mite. The consecutive offspring are females. Development from egg to maturity takes 6-7 days. Once mature they mate with their brother inside the cell. When the pupa emerges as a fully formed bee several young female mites will exit the cell along with their mother to repeat the cycle. The male mite and any immature female mites die upon uncapping of the cell.

Each female may live for 2-3 months and complete 3-4 brood cycles. In ideal conditions from a single mite entering a hive it is possible within its life span to generate a population of almost 200 mites. A mite population of over 1000 mites is deemed unacceptable and the tipping point in terms of colony health. Only a handful of mites surviving a treatment can lead to the threshold population establishing again in a matter of months therefore effective and regular intervention is required.

By mark patterson 08 May, 2019

For many years there has been growing concerns about the increasing numbers of managed honey bees in Greater London versus ever diminishing floral resources that honey bees and other pollinators rely upon.

One of the first influential figures to propose such a statement was LBKA's former chair and beekeeper to the Royals John Chapple who openly stated that he felt there were 'to many bees' in some parts of London more than a decade ago.

At first suggestions that there are too many honey bees in London was met with scepticism (some of which was not very pleasant) one London Bee Farmer went as far as to call the suggestion 'Bullshit' but has since redacted that statement and now thinks there's some truth in the statement. Naysayers were quick to point out that London is almost 70% greenspace and there's plenty for bees to forage on. What the Naysayers dont appreciated though is that whilst the city may appear green much of the greenery is green desert for pollinators offering no pollen or nectar to support their populations. But before I get onto habitat for bees lets first take a look at the nutritional and caloric requirements of a typical honey bee colony.

Carbohydrate

Firstly bees whether they be bumblebees, solitary or Honey Bees rely on plants for food. They   need energy rich carbohydrate food to fuel their metabolism and power flight. Unlike most other insects bees are actually more like endotherms and generate their own body heat through consuming calories and vibrating their thoracic muscles to increase their body temperature. This consumes a lot of energy. 

Bees meet their caloric requirements in the form of nectar which is fuel for their metabolism but in the honey bee its also the raw building materials for their nest as they use it to fuel the wax glands in the abdomen which they use to build the wax comb. Honey Bees also store nectar as honey to see the colony through the winter when there is a shortage of blooms to feed upon.

Nectar is mostly water and sugars (fructose, glucose and sucrose plus other forms of sugars in various concentrations)Nectar also contains trace elements and micronutrients (that sugar syrup dose not contain).

A honey Bee colony is a large super organism and has a very large caloric requirement. In summer a full strength Honey Bee hive contains around 50-60,000 workers and needs to consume around 1800 calories per day - the same as an adult human. In winter their mass and caloric intake reduces enormously and is more like that of a cat or small dog.

On an annual basis a typical colony collects 300-500 lbs of nectar just to rear its worker force which is an annual turnover of 200,000 worker bees (standifer 2008). That's a couple of bath tubs of nectar just to rear the colony's worker force. Wild bees dont live in huge colonies and their energy requirements are substantially less. A paper published by Cane et al  in 2016 established that the forage needs of a single honey bee hive between June and August could provision the nests  and progeny of 100,000 leafcutter or mason bees. Honey bee hoover up enormous nectar and pollen resources from the surrounding environment to meet their energy and nutritional demands.

Factor in the volumes of nectar required to produce new wax combs (up to 8 litres per lb of wax), enough nectar to produce enought honey to see them through winter (40 lbs of honey which might require up to 6 x the volume of nectar when you factor in the energy needed to fuel the metabolic process of turning nectar into honey plus the nectar to honey itself) and then produce a honey crop for its master a typical colony can easily hoover up over 100 gallons of nectar per year.

London has around 5,500 registered bee colonies, factoring in all the ones that are not registered (there's quite a few) and going by a conservative estimate of 6,600 colonies, If all the honey bee colonies in London were gathering this volume of nectar then each year they would gather enough nectar to fill the Olympic Pool at Stratford...That's a mind boggling amount of nectar!

By mark patterson 09 Mar, 2019

February is typically a very cold month of the year. According to the MET office the 17th February is on average the coldest day of the year however this year it was far from being cold. We’ve had a very mild February this year one that has broken all previous records for being the warmest February since records began and beating the record for the warmest winters day since records began. In late February 2019 the mercury rose to 21 degree Celsius in parts of London and the South East of England – temperatures we usually enjoy only in summer.

This very mild winter follows 2018 as being the hottest British Summer ever on record and in fact the past 3 summers in succession have broken all previous records for the highest summer temperatures. In summer 2018 we had a severe drought across much of Southern England with some parts of the country going without rain for almost 4 months.

We’ve also had more than our fair share of extreme weather events in recent years with sudden torrential downpours of rain leading to intense flooding events, sudden snow blizzards and freakish storms becoming more and more frequent. It’s not just here in the UK where these extreme weather events have become more noticeable. The recent artic like conditions to hit the USA’s Midwest is also evidence of climate change. This winter Chicago was subject to temperatures colder than Antarctica and the Arctic. Some scientists have said it was warmer on Mars than in Chicago this winter such was the extent of the extreme cold. Meanwhile summer ice cover over the Arctic has hit an all-time low with images of starving Polar Bears raiding human homes for food being widespread in the media.

The change in timings of the seasons has also become more noticeable with many plants now being recorded flowering typically 2-3 weeks earlier than they used to 20 years ago, and many of their pollinators emerging from hibernation even earlier still. In February 2014 the Botanical Society of Britain and Ireland recorded a staggering 300 species of flower in bloom in the British Isles at a time of year when there would normally be fewer than 30.

This is all evidence of climate change.

But what is climate change exactly? Is it the same as global warming? The answer is no , though the two are linked.

What is Climate Change?

Climate change is defined as being ‘a significant and lasting change in the statistical distribution of weather patterns over periods ranging from decades to millions of years. It may be a change in average weather conditions, or in the distribution of weather around the average conditions (i.e., more or fewer extreme weather events).’

Climate Change has been happening since the Earth was formed. Over long geological time periods the Earths temperature and weather patterns have evolved and changed going through multiple periods of cooling and subsequent warming. At either end of this weather pattern continuum we’ve had severe hot periods and at the other ice ages and every variation in-between.

These slow and progressive changes in climate have occurred naturally and are fuelled by many factors including but not limited to variations in solar output from the sun, Changes in the composition of the Earth’s atmosphere influenced by the spread of photosynthetic plants and volcanic activity, Changes to the Earths electro-magnetic field and changes to the Earth’s axis rotation.

These changes normally naturally occur slowly over tens of thousands or millions of years and species of plant and animal either adapt and survive or they become extinct and are replaced by new species which evolve to fill niches left behind by now extinct forms. Slow changes to climate allow species room to adapt and cope or evolve into new forms.

The problem with current climate change is the rate at which the change is occurring. Man-made influences such as the burning of fossil fuels releasing vast volumes of carbon into the atmosphere and striping of the Earths vegetation mean climate change occurs at a much faster rate than has previously occurred and many of the Earths lifeforms simply cannot adapt fast enough to the current changes.

Climate change or global warming?

Many people think of climate change and assume that it means an increase in global temperatures and call it global warming. Climate change is not global warming but global warming is a part of climate change. Confused?

The Earth has several systems which effect global climate and weather pattern stability. The two most important ones effecting the northern hemisphere are the Atlantic conveyor and the  polar jet stream. An increase in carbon emissions and greenhouse gases resulting in an increase in global temperatures effects both the Atlantic Conveyor and the jet stream in ways which destabilise weather systems and effect the climate.

By mark patterson 02 Jan, 2019
On a mild winters day in December 2016 I stumbled upon an active Buff Tailed Bumblebee nest in Acton, West London.
I've frequently observed winter active Bombus terrestris all over London and the numbers of winter active individuals appears to be on the increase.

Bumblebee scientists and authors like Dave Goulson have suggested that factors like climate change, warmer city micro climates and a shift towards planting more winter flowering shrubbery in urban gardens is encouraging these bees to alter their nesting biology.

Increasingly instead of entering hibernation in autumn more and more Bombus terrestris queens are founding nests in autumn and remaining active throughout the winter months. There have been suggestions that these colonies may fair equally if not better than their spring and summer active brethren due to the lack of competition for floral resources during the colder months - most other insects are hibernating.

For several years now the Bees Wasps and Ants Recording Society has ran a winter active bumblebee survey to try and assess the extend to which our bumblebees are active during the winter. Most of the records relate to Bombus terrestris but there have also been records for Tree Bumblebee Bombus hypnorum and Early Bumblebee Bombus pratorum. In 2017 winter there have been records of Bombus hortorum and Bombus lapidarius but these are more than likely queens which were disturbed from hibernation and not examples of winter active nests. Results of the recording effort have informed us that 75% of winter flower visitations by Bumblebees are to a single plant - Mahonia. Mahonia is a tall evergreen spiky leaved shrub which flowers from November to February and appears to produce nectar even in very low temperatures when other plants can't manufacture or metabolise soluble sugars.

So the winter active Bombus terrestris that I found were nothing new but what may be a first time record is discovering the location of the winter active nest which these bees emerged from and following its progress during the entire winter. Having spoken to other bee recorders on the BWARS facebook group it appears that no one else has yet to achieve this feat of biological recording.

Discovery of the nest occured on the morning of 15th December 2016. Whilst walking from my allotment to a nearby school where I was delivering a workshop about bees I noticed a Bombus terrestris worker emerge from a pyracantha bush and fly in a direct line across the street to a large patch of flowering Mahonia. I paused and a few seconds later observed another worker with a large pollen load fly into the same bush.

I stood and observed the bush for about ten minutes and observed several other bees coming and going and was able to locate the nest entrance.  From the amount of activity it was clear that this nest was now well established and must have been started by the queen in October or Early November. The nest was in an abandoned rodent burrow at the base of the bush. The entrance was well camouflaged with leaf litter and rubbish (crisp packet, plastic bags etc). A record was submitted and accepted on irecord. In addition to this record a brief video showing workers emerging from the nest was posted on the UK Bees Wasps and Ants Facebook Page which attracted comments from some of the recording scheme verifiers. 

Workers were again observed leaving the nest to forage on the nearby Mahonia on the 26th December despite very cold conditions that day. I passed the colony twice that day whilst walking to and from the train station and my allotment where my ducks pond had completely frozen over due to the freezing temperatures.

We then had about two weeks of very cold weather when no activity was observed until the 16th January when workers were again seen coming and going from the nest to the nearby Mahonia patch. That same day a worker was observed on Mahonia blooms on Carlton Drive 738 meters NW of the nest site, other workers were observed that day in a community garden 758 meters NW of the nest location feeding on winter flowering Heather and Rosemary and finally at nearby allotments 237 meters to the south of the nest location. The bees foraging on the allotments were seen visiting a winter flowering Clematis and Helleborus orientalis. It has been previously established by various scientists that Bombus terrestris are quite capable of flying a kilometer or more to forage if necessary and experiments have also shown that they have the ability to navigate  back to their nest if released further away than this so it is plausible that the bees recorded almost 800 meters away from our nest were from that colony but they could also just as easily have belonged to another winter active nest in the neighbourhood.

On the 19th January workers were again seen leaving and returning to the nest. By this point the nearby large patch of Mahonia located approx 40 meters away was past its peak flowering and there were increasingly less blooms available for the bees to feed on.

Bees were observed coming and going from the nest at weekly intervals throughout February. Bees were observed foraging on several occasions on the nearby allotments and also on Hebe autumn glory flowering outside a nearby school 272 meters NE of the nest site. On several occasions workers were observed in February foraging on plants in pots in the nearby Homebase Garden centre. Plants being visited included Mahonia, Cycleman, Heathers, Hellebores and Pansies. The homebase store is located 192 meters due east of the nest location. By this point the nearby Mahonia shrubbery had finished flowering.

In Early March the nest appeared to still be active with several queens seen in the immediate vicinity of the nest. There was no way to be certain they had emerged from our nest though.

On the 9th March the nest was still active with workers coming and going. In addition there were several dead and dying bees littered around the nest site. These were all aging workers. This same day the first Hairy Footed Flower Bees of the year were observed on the nearby allotments on Pulmonaria and Muscari.

Over the next week a number of queens were observed foraging within a 700 meter radius of the nest. These queens could have quite easily been bees emerging from hibernation and are no proof of successful reproduction from the winter active nest.

In late March I revisited the nest location and found no activity. A number of dead bees were found among the leaf litter around the nest site which included a tatty looking male - evidence that the nest may have been successful in producing queens and drones before it died out.

I had planned to revisit the nest site shortly after the last observation with the intention of excavating the nest and dissecting the remains to search for clues as to whether or not the colony had been successful in producing queens and drones. Sadly when I returned with a spade to follow through with this plan the Pyracantha hedge had been grubbed out and hording erected around the site as construction of a new housing development had begun on the site.

Its a pity that the nest could not have been retrieved and analysed as the contents may have made for some new discoveries and furthered understanding of winter active nest biology. Im confident that as more and more of these bees adopt a winter active lifestyle it will only be a matter of time before someone again locates a winter active nest and is able to follow its progress through the winter months and hopefully retrieve the nest at the end.

Some interesting observations which raise further questions about winter active nest biology.

I have stumbled upon plenty of spring and summer active Bombus terrestris nests over the years. Early on these nests tend to produce workers of varying size. Some of the workers are initially very small and diminutive whilst others are larger and more robust looking. Later on in the life cycle of the colony as the colony produces fewer workers and invests more resources in producing queens and drones the workers seen leaving nests are also much smaller and diminutive than normal. In his book a sting in the tail Dave Goulson talks about worker size variation and attempts to explain possible causes for this phenomena.
The winter active nest observed seem to produce workers which were all quite large in size. No small diminutive workers were observed (though they could have been present inside the nest and out of sight). This has me thinking whether  these smaller workers survive in winter when  smaller bees with a higher surface area to mass ratio would lose heat more quickly and be less effective foragers in the cold temperatures.

The longevity of the nest also seemed to be longer than most spring and summer active nests. Spring nests of Bombus terrestris are typically founded in March/Early April and By June have produced sexuals. Second generations then produce sexual reproductives by September meaning most colonies from start to finish span about 3 months. This nest would have been founded in October or early November as it was well established when discovered on the 15th December. The nest persisted until early March meaning its active period spanned approximately 5 months. Do these winter active nests typically tick over at a slower pace than their summer counterparts?

These are all questions which would make for a fascinating study if more winter active nests can be located.
By mark patterson 01 Jan, 2019
'Bees and flowers go together' is the big message which the London Beekeepers Association  is trying to put out there to the public in an attempt to encourage more Londoners to grow for bees and other pollinators in the city environment.

The association has evidence based data that in some areas of the capital bees are struggling to find sufficient food as we loose green space, patches of flowery habitat decline whilst at the same time continuing to experience a rise in the number of Honey Bee Hives.
Many people want to help bees and assume that the best way to do so is to become a beekeper themselves and get a hive of bees. The associations message to the public is that everyone can help bees by planting for them and you dont have to become a beekeeper to help the bees.

When my beekeeping association decided it would like to give out packets of bee friendly flower seeds to the public  to help spread this message I was tasked as forage officer with choosing an appropriate mixture.

The brief was short and simple, we needed a seed mix that was:
  • Great for bees
  • Cost efficient for us to buy in bulk and distribute for free with the funding we had available
  • Easy to grow
  • Looks good and is suitable for growing in an urban environment
  • Suitable for pots and containers as well as directly in the ground
  • Would cope with a variety of soil types including London Clay
Having a background in ecology and horticulture I was familiar with most of the seed suppliers offering various different sed blends having already used many of them myself on previous planting projects. But there were also some which I hadn't yet tried for myself so I decided to trial them to see for myself which ones worked  best.

I started by comparing the prices of available seed mixes. I put these into a table and then went out and bought packets of the annual mixes I wanted to trial.

I set up a series of 1 meter square growing beds at the Westcott Park Community Garden, a bee friendly community garden I designed and built in 2011. In each bed we sowed a different seed blend sowing at the suppliers recommended sowing rate. Seeds were all sown in late March and monitored until the end of the growing season. The mixtures we trialed were all annual mixes. We wanted to give out annual mixes because they are quick to establish, low cost and the ease of growing encourages first time gardeners with little to no experience or confidence to give them a try.

Mixtures grown were:
  • Flower Scapes flower power mix
  • Flower scapes monet mix
  • Flower scapes Van Goth Mix
  • Nature scapes corn field annual mix
  • Naturescapes deluxe annual and biennial mix
  • Pictoral meadows by Nigel Dunnet Classic mix
  • Meadow in my garden/Nova Flora Bees Mix
  • Really wild flowers native cornfield annual mix
  • Grow Sure pastel colours mix
  • Grow Sure red hot mix
  • Miracle Grow Flower Magic mix
For each mix a bed was prepared in garden top soil by digging over the ground, removing any weeds and weed roots. The soil in the garden was heavy london clay so this was broken up and had sharp sand and compost added to improve the growing conditions. We then scattered the seed onto the ground and lightly raked in and watered. Seeds which came blended with coir and or seed husks such as the Nova Flora and Grow Sure mixtures were sown direct from the packet. Other seed mixes containing only seeds were mixed with a little soft sand to aid in sowing. This helps to ensure an even distribution.

I monitored the growth of the flowers over the whole season noting the number of different flower varieties present in the mix, ease of germination, how they performed aesthetically, number and variety of pollinators which each patch of flowers attracted and the length of time each mix flowered for.
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