Pollinator Decline

Pollinators, including honey bees, are in decline all over Europe due to habitat loss, climate change and modern  agricultural practices. All the usual culprits. This is fact.

Anybody in doubt about that should cast their minds back to the good old days when car windscreens would be so plastered with crushed insects – regular stops were needed to scrape them off.

Mind you, cars were rather less streamlined then and a bit more – er – ‘boxy’:

Einstein

Einstein said, “If the bee disappeared off the surface of the globe, man would have only four years left to live“.

They now say he probably didn’t say that at all but then they would wouldn’t they.  Whether he said it or not – the bleak nugget of truth in that sentence seems to have reached most people.

Threatened Pollinators

Ireland’s wild pollinators include 20 species of bumble bee, 77 solitary bee species plus 1 species of honey bee. All of these are entirely dependent on flowers to exist so it is bees that carry out most of the pollination services.

33% of these are threatened with extinction.

Other pollinators include flies, butterflies, moths, wasps, ants, beetles.

Between them, their pollination services are thought to be worth €153 billion worldwide and at least €53 million in Ireland.

In response to the very real threat to these insects and (god forbid) the economy, many countries including Ireland have put in place plans to attempt to reverse the trend of pollinator loss.

Ireland’s Pollinator Plan 2015 – 2020

Biodiversity Ireland with Trinity College Dublin and a 15 member steering panel of experts have devised a 5 year plan to address pollinator decline and protect the pollination service these insects freely provide to agriculture, horticulture and the countryside in general.

 Objectives

The plan has 5 objectives:

• Making Ireland pollinator friendly.
  Pinpoint things that can be done on farmland, public land and private land, to create an interconnected network of wildflower-rich pollinator-friendly habitats.
• Raising awareness of pollinators and how
  to protect them.
  Increase awareness of the importance of
  pollinators and the resources they need to survive.
• Managed pollinators – supporting beekeepers and growers. To achieve healthy, sustainable populations of managed pollinators that can play a full role in delivering pollination services.
• Expanding our knowledge of pollinators and pollination service Increase research and knowledge to find the best and most cost-effective ways to protect pollinators.
• Collecting evidence to track change and measure success Survey pollinators and monitor change to ensure the Plan is working.

Eighty one actions have been indentified to achieve these aims and have been shared out among sixty-eight governmental and non-governmental organisations which have agreed to support the plan.

The recommended actions include:

Hedgerows

Planting new hedgerows with native species such as hawthorn, hazel, willow and blackberry etc. Old hedgerows should be maintained properly and cut less often. Vegetation at hedge bases should not be sprayed so wild flowers are conserved.

 Wildflowers

Should be encouraged along hedges, lanes and field corners. Buffer strips containing native wild flowers should be planted along field margins and cut between September and April only. Further management practices can include grazing to conserve and improve these areas.

Nectar and Pollen rich shrubs and trees

Planting of willow, hazel, hawthorn, horse chestnut and blackthorn in hedges and field corners, parks, schools etc.

Nesting Areas

Tussocky grass and nettles provide nesting areas for bumble bees. Bare uncompacted ground for solitary bees.

The Other Bits

I added the photo below to demonstrate just how much land is not hedgerow or hedge base. When these fields are planted with rye grass, rye grass, rye grass  or in modern day crop rotation of barley, barley, barley, wheat, barley, they are as about as useful to bees and other pollinating insects as these flooded fields:

Funding

The plan points to government initiatives that are already in force and it is hoped that communities and local authorities will formulate projects and seek funding from local and national government. There is also the possibility of funding from Europe.

Honey Bees

All of these measures will help honeybees and that is to be welcomed. However, apart from the spectre of mapping and education on diseases the plan is a bit short on specific help for honey bees. All beekeeping associations already provide education on diseases.

The plan describes honey bees as being ‘domesticated’ or ‘managed’.

Domesticated

Before the Varroa mite, which came in with imported bees in 1999 or thereabouts, the honeybee lived as wild as all the other Irish pollinators. Until recently it was thought to be extinct as a wild species but recent research has shown that Ireland’s native bee – Apis mellifera mellifera is in fact alive and kicking in the wild. Presumably it is adapting to cope with Varroa – perhaps becoming swarmier.

Imports

It is a shame that no steps are suggested in this plan to prevent further imports of foreign bees and the exotic pests that come in with them. That would have helped to protect the honey bee.

Managed

Also the plan says this, “The needs of managed honeybees are very different to those of wild pollinators. Beekeepers can move colonies to where forage sources are available, and can provide extra resources over the winter.”

Well, that’s just not true. The majority of beekeepers in Ireland are hobbyists – that is they have a couple of hives in the garden and no other apiary.

To move bees, you need to have somewhere to take them and you need the know-how to move them. It’s not a walk in the park you know. Moving bees is stressful for both bees and beekeepers. It is not for the fainthearted – it is ticklish, potentially dangerous and certainly not for the novice. But that’s for another post.

Conclusion

Much is made of planting wildflowers but there are wildflowers and there are wildflowers. Anyone thinking of sowing wildflowers should try and get Irish natives. Foreign wildflowers evolved with foreign insects and may not be appropriate here.

Irish wildflower seed is available from Sandro Cafolla – more info on his website www.wildflowers.ie

Click here for Biodiversity Ireland and the Ireland Pollinator Plan

Click here for Irish Wildflower seeds

Click here for Hedgelaying Ireland

Click here for more about Bees and Climate Change

Click here for Bee Trees – Hawthorn

Click here for Bee Trees – Hazel

Click here for Bee Trees – Ivy

Click here for  Bee Trees – Horse Chestnut

Click here for  Bee Trees – Sycamore

Click here for Bee Trees – Willow

Click here for Bee Trees – Lime

Click here for Bee Trees – Poplar

Copyright © Beespoke.info, 2015.  All Rights Reserved.

From an ecological point of view there are at least 3 reasons:

• Honeybees have evolved in tandem with certain flowers and they have adapted to facilitate each other;
• One bee is able to rapidly communicate the location of a pollen/nectar source to the whole hive and an army sets out;
• The bees then concentrate faithfully on that flower species until the pollen runs out or the nectar dries up, at which point the job of pollination is accomplished.

These features obviously make the honey bee important from an agricultural/commercial point of view. In addition, hives of bees are mobile and can be moved from crop to crop – an arrangement which can suit bees, farmers and beekeepers so long as everyone has a bit of respect. Wouldn’t that be great?

But some detail:

Evolution

In the beginning there was the wind…

The earliest seed-bearing plants were randomly pollinated by wind-borne pollen which would be caught on droplets of a sticky exudation oozing from their ovules. Because of the hit and miss nature of this method of pollination massive amounts of pollen need to be produced in the hope that at least some of it will find its mark. This method is still used by conifers.

Then came the insects…

It is thought that eventually sap-sucking or resin-browsing insects were drawn to dine on the exudation. The effects of this were beneficial to both parties – the insects were introduced to pollen as a  new source of protein and as they moved around from plant to plant they carried pollen with them and pollinated as they went. Plants pollinated in this way needed to produce less pollen than those still relying on the wind. Insect pollination was also more efficient so these plants were able to produce more offspring and the trait persisted.

Co-evolution

As long as such associations are mutually beneficial, their continuance is at least assured and there may even be further co-evolution. Each step along the co-evolutionary pathway creates a more fruitful relationship although things are more prone to disaster.

Over-dependency

Occasionally a plant may devise an almost perfect method of manipulating an insect for pollination purposes but such cases are so complex they tend to involve a single species of insect. One of the best examples of this is the flower of the orchid Ophrys speculum which looks enough like the female of a certain bee species (not Apis mellifera) to entice pollen coated male bees to mate with it and thus pollinate it in a novel way. While this may be a highly successful method of pollination, the future of the orchid becomes tied in very closely to that of the bee; if the bee species should decline or even become extinct, perhaps due to habitat destruction or a surfeit of exhausted males, then the orchid will be doomed to follow.

Honey bee adaptations

The honey bee has not yet been so tightly hemmed in by co-evolution and they remain relatively broad spectrum pollinators. However they have evolved certain adaptations that suit them for their job such as tube-like mouthparts for reaching down into the throats of flowers in search of nectar and the hairy body which is the ideal surface to which pollen grains will easily cling. There are also pollen baskets but these are designed not for the passing on of pollen but to collect the bee’s share to take home to the hive.

Bee flower adaptations

Plants, for their part, have adapted their flowers to attract bees – all sorts of bees. They tend to have  brightly coloured petals, usually blue or yellow, with a landing platform of some sort. The petal markings may include honey guides which are designed to tell the bee where the nectar is. The nectaries are tucked away near the base of the corolla tube, where only the tube-like mouth-parts of a bee can reach and inaccessible to the chewing of beetles.

There are also cunning floral booby traps designed to manipulate the insect pollinators:

• Scotch broom – Cytisus scoparius  is spring-loaded to burst open when a bee lands, the curved stamens and stigma arching over the bee; the stamens to press pollen onto its back and the stigma hoping to pick up some suitable pollen placed there by another broom plant.
• Gorse (Ulex europaeus) is also spring loaded but in this case the stigma and stamens burst from the floor of the flower, hoisting the bee into the air. Here the target must be the bee’s belly.

• Rosemary officinalis is not sprung, but has stamen and stigma strategically arranged to arch out of the upper part of the flower in such a way as to brush the bee’s back.
• Himalayan balsam or Impatiens glandulifera has stamens situated above the entrance of the flower so as the bee pushes its way in – a streak of white pollen is plastered onto its thorax

• Meadow sage or Salvia pratensis has a carefully placed foot-plate which is hinged to the stamens, when the bee treads on the foot-plate the stamens swing down from the roof of the flower stamping pollen onto its back.  The stigma, meanwhile, extends from the upper lobe of the flower and lengthens with age so that bees entering an older flower brush against it on the way in so delivering the pollen. Presumably this age-related lengthening is a mechanism to avoid self pollination. Click this fabulous photo below for a close up of Salvia pratensis pollination in action – not mine and not a honey bee – all credits to Wikimedia.org

So a day in the life of a honeybee can be quite a circus, hoisted into the air one minute and thumped on the back the next.

Honey bee exclusion

Some flowers have evolved to exclude honeybees in favour of other insects.

A common method of exclusion is by having corolla tubes too deep for the bees’ elongated mouthparts and these are butterfly flowers. An example would be honeysuckle (Lonicera periclymenum).  Unimaginative though – don’t you think? How about weight activated trapdoors, ejector seats or that old favourite – a boxing glove on a spring.

However, exclusion can backfire. Some insects are clever enough to chew a hole into the corolla tube to access the nectaries bypassing the pollination step altogether. Honey bees will sometimes use these access holes too.

Another exclusion method is an open door policy. Primitive flowers such as composites (daisy-like flowers) are open to all and sundry. These are little visited by honeybees as they are not mixers by nature and dislike competition.

Wild carrot (Daucus carota) flowers are white composites but they sometimes have one small red flower in the centre (above).This is thought to attract flies who think the little red dot is another fly and flies are great mixers. Just look at horse muck!

Communication

The foraging force of any one hive may number 25 thousand and they will cover the area within a radius of 3 miles from the hive  in search of nectar and pollen. When they find a good source, they become very purposeful, they load up with pollen and/or nectar, then they go back home to the hive. Once home they will hand out samples of what they have found and dance enthusiastically to tell everyone where it came from – how far, how much and which direction. Bees that respond to the dance and go out and find the source are said to be ‘recruited’. For bees, this means they will go out after this species of flower until either they die or the source does. Communication means that a chance discovery by one bee will lead to thousands and thousands following on and obviously the more bees the quicker will be the pollination.

Good Youtube video on dancing bees here:

Fidelity

The fidelity bees show for a single species helps pollination in several different ways.

• Once they have been discovered by the bees, increasing numbers of bees are recruited to forage on that species moving from flower to flower depositing pollen as they go.
• They will continue to visit until either the nectar dries up or the weather changes. They make the most of spells of good weather.
• When the bees return to the hive they all tumble around together in the hive, passing pollen from bee to bee as they brush shoulders. This increases the likelihood of cross pollination as bees will then be carrying pollen from several individuals of the same species.
• Focussed attention means plants need not produce so much pollen.

Mobility

From a commercial/agricultural point of view, hives of bees can easily be moved from crop to crop where all of the above apply. Bees are regularly employed to pollinate crops of oil seed rape, borage (star flower) and top fruit in the UK.

Meanwhile in the USA, fruit farmers and beekeepers have evolved a highly efficient annual migratory existence following a variety of crops west to east by the truckload across the country. They are paid for their services as pollinators and of course there is the honey too. Crops they are paid to pollinate include apples and pears, cherries and almonds, melons, cucumbers and squash, cranberries and sunflowers. For honey there are orange blossom, alfalfa, California buckwheat, blueberries, Brazilian pepper, palmetto, basswood, clover and gallberry to choose from.

It could be said that they have, between them, created a specialist relationship like the delicate orchid/bee example above. One that is very focussed and even efficient but also very vulnerable and we’ve seen what can happen with the disastrous Colony Collapse Disorder.

Here in Ireland, while farmers will welcome beekeepers onto their land when they are growing oilseed rape or apples etc there are few who will pay the beekeeper to move.

But read on…

The Future

The drive towards increasingly intensive agriculture is accelerating. Each year, more hedgerows and patches of scrub are ruthlessly wiped off the landscape and mixed meadows  reseeded with rye grass. Habitat destruction causes the extinction of wild pollinators and this may lead to an increase in demand for mobile beekeepers here but we should know where that stuff leads.

But always look on the bright side of life – that’s my motto!

Click here for the mechanics of Pollination

Click here for more on Gorse Pollination

Click here for more about Himalayan Balsam

Click here for Ireland’s Pollinator Plan 2015-2020

Sources

Attenborough,D.  Life on Earth – A Natural History. BBC, William Collins and Reader’s Digest. 1979.

Campbell,N.A.  Biology – Second Edition. The Benjamin Cummings Publishing Company Inc. USA. 1990.

Mairson,A.  America’s Beekeepers – Hives for Hire. In National Geographic Vol. 183 No. 5. 1993.

Raven,P.H., Evert,R.F. & Eichhorn,S.E.  Biology of Plants. Worth Publishers Inc., New York. USA. 1986.

Copyright © Beespoke.info, 2016.  All Rights Reserved.

Or you might wonder – ‘IS there a flow at all?’ Because often there isn’t and you can never tell in advance if it will or if it won’t. Heather honey is the most bewitching and frustrating of all honeys; if you can get a crop of sections or cut comb honey it’s close to heaven and so costly and disappointing when it fails.

But there’s more to it than the weather. It’s the ecology – Stupid!

Distribution

Calluna vulgaris or Ling heather is widespread at all altitudes across Northern Europe from Spain to Scandinavia and from the Azores to the Urals but tends to dominate where the environment is harsh and/or nutrient stressed. As we all know, it tolerates extreme cold without damage but it is intolerant of shade.

Soil

Calluna is seldom found in fertile lowland situations because it is a ‘calcifuge’ ie it can’t bear limey or base soils but likes instead, an acid soil. This tends to make it a plant of stressed environments, either mountain or bog where excessive rain and cold create acid soils which are also usually low in available nitrogen.

It can get a foothold in moderately receptive soil environments. Once established, the cast-off leaves decay to a dark brown acidic humus. In this way Calluna is able to adapt certain soil environments to suit its own requirements.

Moisture

While Calluna is almost always found in areas of high rainfall – it is actually intolerant of waterlogging and grows best where there is moderate drainage. In super-saturated areas Calluna tends to give way to Ericaceous heathers ie Erica tetralix or E. caerulea – also Molinea caerulea or Purple Moor Grass.  Where Calluna is found growing in bogs, the roots tend to be restricted to the top few inches of peat and above the upper extent of the summer water table. If this is still too wet – it will pull up its skirts and occupy the hummocks.

Growth Habit

When it finds conditions it likes – C. vulgaris is a long lived, woody dwarf shrub – often reaching 30 and even 35 years old. The life cycle is divided into four phases:

• Pioneer – 3-6 years – flowering after the 1st year;
• Building – Up to 15 or 20 years. Densely branched shrub with maximum canopy cover and nothing growing beneath. Flowering freely;
• Mature – Over 20 years. Plants become leggy – up to 1.2 metres – with mosses and lichens beginning to occupy the open area at the centre of the plant;
• Degenerate – Over 25 years. Central branches die out leaving a gap which may be colonised by other species perhaps upland trees such as Rowan or Scots Pine before young Calluna plants can establish.

For the beekeeper, the Building and Mature phases are most useful to the beekeeper as they can give rise to vast areas of carpet-form heather which is when flowering is most profuse.

Careful burning of heather at intervals in concert with managed grazing can remove stands of degenerate heather and create instead a shifting mosaic of different aged stands of heather which are of great benefit to wildlife – especially Red Grouse (Lagopus lagopus), many species of bees and other insects. Beneficial to Hill farmers also.

Burning correctly is a skill. Ideally the fire should only kill over-mature specimens leaving younger plants to regenerate from the base and creating space to allow seeds to germinate. A slow moving fire over dry peat can get too hot, killing all heather plants and destroying the seeds present in the seed bank. In such cases regeneration is slow, if at all, and other species may move in instead. And there may be soil erosion.

Grazing

Calluna benefits from moderate browsing which can promote the aforementioned dense, single-species, topiaried carpet.

Sheep and Deer are browsers rather than grazers such as cattle: they pick and choose – mostly young shoots which is like light pruning and beneficial in its effects. However, overstocking of  sheep/deer forces them to browse more deeply, and damagingly, into the woody heart of the plant. It also reduces the ability of heather to regenerate; young plants are unable to establish or are grazed to extinction leading to thinning stands of gangly, senescent heather. Excessive trampling creates bare patches leading to soil erosion or invasion of other less valuable species.

Cattle are disastrous for heather – they graze indiscriminately and their great heavy feet cause severe damage to soft peaty soils leading inevitable to soil erosion.

Heather also provides habitat for the Red Grouse (Lagopus lagopus) which relies on heather for 90% of it’s adult diet. It also requires heather of varying ages  for shelter and cover and areas in which to nest and to rear young. The young birds are reared on insects foraged in the heather – the only carnivorous phase in the bird’s life. As such it is completely dependent on heather for its life-cycle.

I never heard of overgrazing by grouse – instead this bird can be regarded as the ‘canary’ when recognising when conservation is necessary. In other words – if it is absent or dwindling from heathery uplands something is wrong. Click here for the Irish Red Grouse Association.

Heather Beetle is a wild creature whose boom-and-bust life cycle can lead to overgrazing by the larvae and even death of great swathes of heather. Sometimes the whole system is replaced by other less desirable vegetation communities such as Molinia caerulea  aka Purple Moor Grass with or without assorted sedges and moss. This creature, the heather beetle is also known as Lochmaea suturalis. Here it is:

In a ‘normal’ year, heather beetle harmlessly carries out its life cycle eating heather leaves and hibernating in the soil. However in some years the population rockets and the heather suffers a beetle-grazing epidemic to the extent that extensive areas are wiped out.

Here’s a picture of severe heather beetle damage in a lowland raised bog, Narraghmore, Co.Kildare:

Pollination

The flowers of Calluna are able to both self and cross pollinate but an outside agent either the wind or an insect is required in both cases. In experiments where flowers are enclosed and outside agents excluded, pollination does not occur.

If you look closely at the flowers of C. vulgaris you will see that the arrangement of pollination paraphernalia lends itself to a generalist approach enabling both insect and wind transfer of pollen.

Either way, once a flower is pollinated by the wind or another insect rather than one of your honey bees, the secretion of nectar dries up!

Wind Pollination The pollen-bearing anthers are safely enclosed within the heather flower. When weather is damp and wet, the pollen remains clumped on the anthers and is not washed away by the rain.  When weather is dry and windy, however, it is liberally shaken out and blown hither and yon. The stigmas meanwhile are out in the elements where they can obviously take advantage of passing clouds of pollen. So if there is a long period of dry windy weather and the flowers are quickly wind pollinated the likelihood of a strong nectar flow is reduced.

Here’s a picture of my dog Bunty in the heather. She used to love a trip to the hills but the poor girl was the victim of a pollen allergy and the free release of heather pollen on a sunny day would set up such an itch she would spend most of her time rolling around and scratching till she bled.

Insect Pollination  We are all familiar with the buzz of activity in the flowering heather what with bumble bees, honey bees, butterflies and others. Flowers are visited by about 35 species of insects.

Nectar to attract insects is secreted from nectaries inside and at the base of the flower below the anthers.  As such, visiting insects inevitably transfer pollen from their bodies onto the stigma and pick up pollen from the anthers as the reach down for the nectar.

Bumble bees and honey bees are the most efficient pollinators as they carry the most pollen and they get up very early in the morning!

Thrip pollination The architecture of heather flowers does not allow for rain pollination. However where Calluna lives it can rain for days or even weeks on end.  No surprise then, that heather does have a trick up its sleeve for those wet years when neither wind nor flying insects can do the job.

There is a tiny creature – a thrip – called Taeniothrips ericae – which is found on both Calluna and Ericaceous heathers. It spends almost its entire life cycle within the flowers, romping about between the anthers picking up pollen and eating nectar.  There are about 4-6 thrips per flower but male thrips are rare. As a consequence females leave home on sexual maturity and roam from flower to flower looking for a mate. The picture below from Hagerup (1950) shows a female thrip using the stigma of a flower as a launch pad (Figure 2.). No doubt she lands on many of these during her wanderings and inevitably pollination must occur. Later work in Norway by Haslerud (1974)  concluded that pollination by thrips was only significant in very wet climates. Click picture for a close up.

By the way, pollination aside, these insects have the same boom and bust life cycles as the heather beetle and Irish developers. In boom years each flower may be full of baby thriplets eating all that heather nectar before our bees can get there. And you know yourself how the honey bee hates competition – they’ll just go for the ivy instead!

In Essex I remember plagues of tiny black corn thrips or ‘Thunderbugs’;  some years the air would be full of them. They’re probably extinct now.

A Hardy Plant?

In the absence of over-grazing by mammals, birds or insects – Calluna fares surprisingly well in hostile environments on acid/nutrient poor soils and in cold, wet, upland areas with strong winds etc. It grows quickly into a large, long lived, vigorous plant which puts out a profusion of flowers year on year.

How does it do it?

Read on…

Mycorrhizal Symbiosis

To cope with the stresses of the very extreme environments of mountain and bog, Calluna has evolved a  symbiotic relationship, with an assortment of soil fungi including Rhizocyphus ericae and Phialocephala fortinii complex. Fungi involved in these symbioses are termed Mycorrhizae or ‘fungus roots’.

Don’t go away – this is simpler and far more interesting than you can imagine!

Here is the simplified basis for Calluna’s mycorrhizal symbiosis:

• Calluna is nitrogen-limited because there is so little available in the stressed environments it inhabits but it does have an unlimited supply of carbon which it captures from the air via photosynthesis.
• Fungi, on the other hand, are enzymatic powerhouses – well able to break down acidic litter and suck up nitrogen in conditions which thwart most plants. As a result, soil fungi have an abundance of nitrogen but they are carbon-limited.

The roots of the heather link up with microscopic fungal hyphae thus plugging themselves into a fungal network of mycellium which ramifies outwards through the soil breaking down litter and supplying nitrogen to the plant which in return supplies carbon products to the fungus.

There’s more – these fungi are termed endomycorrhyzas which means they actually penetrate the roots and grow inside the plant as well – a hand in glove relationship! Fungal hyphae can be found throughout the plant even as far as the ovules with their ripening seeds. Sounds a bit like The Borg (1992,1996) don’t it? Researchers believe that in this way, plants are inoculated with their mycorrhyzal partners when they are seeds – how clever is that!

Conservation

A survey of potential Red Grouse habitat in Ireland in 2008 revealed 22% of the total grouse habitat to be severely damaged by overgrazing, 30% moderately damaged while only 34% remains undamaged. For Red Grouse Habitat read Calluna vulgaris.

It should be of concern to beekeepers as well as sheep farmers that over 50% of total heather is damaged.

Sources

Crushell,P. & O’Callaghan, R.J. (2008) A Survey of Red Grouse (Lagopus lagopus) Habitat in Ireland 2007 – 2008: an assessment of habitat condition and land-use impacts. Report for BirdWatch Ireland & The National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Ireland.

Gimmingham,C.H. (1960) Biological Flora of the British Isles: Calluna vulgaris Journal of Ecology

Hagerup, O. (1950). Thrips Pollination in Calluna. K. Danske vidensk. Selsk., Biol. Medd., 18 1-16

Hazard.C., Gosling.P., Mitchell.D.T., Doohan.F.M. & Bending.G.D. (2013) Diversity of fungi associated with hair roots of Ericaceous plants is affected by land use. Article first published online: 28 NOV 2013. DOI: 10.1111/1574-6941.12247. © 2013 Federation of European Microbiological Societies

Haslerud, H.D. (1974) Pollination of some Ericaceae in Norway.
Nord. J. Bot. 21: 211–216.

Mahy, G., De Sloover, J., & Jacquemart,A. (1998) The generalist pollination system and reproductive success of Calluna vulgaris
in the Upper Ardenne. Can. J. Bot. Vol. 76 1843-51

Mohamed, B.F. & Gimmingham,C.H. (1970) The Morphology of Vegetative Regeneration of Calluna vulgaris. New Phytologist. 69, 743-750

Rayner,M.C. (1925) The Nutrition of Mycorrhiza Plants : Calluna vulgaris. Journal of Experimental Biology

Star Trek: The Next Generation: I Borg  Season 5, Episode 23 (1992)

Star Trek: First Contact (1996)

 Copyright © Beespoke.info, 2015.  All Rights Reserved.

There are three castes in a honeybee colony: the queen, the worker and the drone. There is only one queen per colony and she will live for about three years. During her reign there are numerous workers although the numbers of workers per colony fluctuates with the seasons reaching a peak in early summer and dwindling to a minimum in the depths of winter. In the early summer the colony begins to produce drones who emerge to live the life of Reilly until the end of the season when they are forcibly evicted to die in hungry heaps in the long grass.

The details of the control of the complicated demographics of the honeybee colony are for another day! Only the mechanisms of how the colony manages to produce three castes from two sorts of egg will be dealt with below.

Cross your fingers and click table for bigger picture.

There are three phases of development – the egg, the larva and the pupa.

The Egg

All three castes come from eggs laid by the queen, however the queen can only lay two kinds of egg – fertilised and unfertilised. Fertilised eggs become females, that is workers or queens, while unfertilised eggs become males – the drones. So the egg-type sorts out the most fundamental differences between the castes – sex. Unfortunately there are only two sexes and three castes so something else must cause the differentiation of queen and worker.

The Cell

Honeybees build three sorts of cells for their queen to lay her two types of eggs in.

• Small hexagonal worker cells;
• Large hexagonal drone cells;
• Downward pointing, cup-shaped queen-cells.

It is not known how the queen knows to lay fertilised eggs in small hexagonals and unfertilised eggs in large hexagonals but Hooper suggests she measures the cell top with her forelegs then acts accordingly. All fertilised eggs can become either queens or workers but it depends entirely first of all on how they are housed and secondly how they are fed subsequently which influences larval development.

Larval Development

All honeybee eggs hatch after 3 days into small crescent shaped larvae whose mission in life is to eat-eat-eat. To this end they are fed bee-milk by the nurse bees. Bee-milk is produced by glands in the heads of the nurse bees and it contains just what a baby bee needs for healthy growth and development.

Drones and worker bees are fed as much as they can eat for about 3 days after which they receive smaller daily rations until the cell is sealed, drone cells having domed cappings which help accommodate their larger bulk. Cells are sealed between 8 and 10 days, drones taking slightly longer than workers and queens (see Table 1.).

While the workers and the drones are getting their bee-milk rationed, the larval queen or queens continue to float in it in their deluxe, queen size cells and continue to be fed as much as they can eat until they are capped. The bee-milk fed to queens contains more sugar than that fed to workers and because it seems to have queen-making properties it is called royal jelly.

During this growth period queen larvae increase their weight by about 3,000 times and workers by 1,500. Such a rate necessitates five laval moults, four before capping, the fifth shortly after. Much of this increase in weight is as stored fats, carbohydrates and proteins, which are to be used in the next phase to convert the simple maggot-like larval body into that of the more complex adult insect with hopes and dreams and a lust for life.

Metamorphosis

Until the cell is capped the larval stomach is shut off from the intestines in other words it is a simple sac with no exit. Once the cell has been capped the larval stomach is plumbed in to the intestines and waste is evacuated via the anus into the inner end of the cell. The larva then spins the cocoon within which metamorphosis will take place, thus forming the propupa, but forming it inside the fifth and final larval skin (Snodgrass). The larva then moults for the last time but it does not shed the skin, instead it is retained as an outer cuticle within which, the body wall of the larva has already taken on the shape of the pupa. This stage is reached at 11 days in the worker, 10 in the queen and 14 in the drone (see Table 1.).

Between this and emergence are 10 action packed days, only 6 in the queen, with numerous big changes taking place. The progress of development can be followed through these days as in Hooper’s table by the colour of the pupa’s eyes, thorax or abdomen. Eventually the larva loses the maggoty shape as some of the 13 larval segments expand while others become constricted to differentiate the head and thorax from the abdomen of the adult insect. The adult head develops from the larva head, the first 3 segments become the neck and thorax and the last 10 become the abdomen although the first of these last ten is tightly constricted connector and strictly more a part of the thorax than the abdomen. According to Snodgrass – projections such as legs, wings and antennae are turned inside out early on. This suggests to me that the larva had them all along, but was wearing them on the inside, like inverted jumper sleeves.

When all the external changes have taken place the larval insides become broken down and digested to build adult organs. When all is complete the young adult splits the pupal shell, chews its way through the wax cell capping and emerges baffled and fluffy to potter clumsily about the brood nest until its cuticle stiffens and the hectic life of work engulfs it – unless it happens to be a drone.

Sources

Hooper,T. Guide to Bees and Honey. Blandford, London. 1991.

Snodgrass,R.E. The Anatomy of the Honey Bee. In The Hive and the Honey Bee. Ed. Dadant and Sons. Dadant Publications. Illinois. USA. 1979.

Copyright © Beespoke.info, 2014.  All Rights Reserved.

Photo from https://beeinformed.org/2012/04/queen-bee-identification/

It is also known as the Grey bee because 3 segments of its abdomen are broadly covered in a thick pelt of short grey hairs which partially conceals the underlying dark abdomen giving it a frosted look. Photo from queen bee identification article on www.beeinformed.org

It is similar to the Italian bee in that it is a medium sized bee with a long narrow body and limbs and it also has the same long proboscis which enables it to make full use of the red clover – an important forage crop in Europe. Here in Ireland, your bees will have to be quick off the mark if you want to get to the clover before that army of sacred cows  known as the ‘Dairy Industry’

Coming, as it does, from a region where summers are predictably long and warm, it has a strong swarming tendency.  In its native range, winters are long and cold so it does fares better over winter than the Italian bee, being very thrifty with a smaller brood nest. In spring, the build-up can be very rapid indeed an adaptation to take advantage of an early flow. If there is one…

Like all honey bee subspecies in their pure form, Carniolan bees can have a gentle nature which is good.  When matings are mixed, aggression can be expected.

Here in the far west of Europe we have our own native bee, the Irish native honey bee, Apis mellifera mellifera,  which has evolved over thousands of years and ‘knows’ how to cope with whatever this clammy, wet and unpredictable Irish climate can throw at it.

If you are thinking of importing Carniolan bees – or buying from somebody else who imports Carniolan or any  other bees for that matter – remember that you will be helping to erode the genetics of the Irish bee.  Ask yourself – why would you want to do that? Wouldn’t you prefer to be a proper beekeeper? Learn to work with your locals and rear your own queens?

Lots of information on that here : Queen Rearing

And don’t forget – small Hive Beetle is out there waiting for somebody just like you. You don’t want to find yourself in front of god explaining why you destroyed your neighbour’s native bee breeding programme and at the same time introduced the most devastating bee parasite to Ireland now do you?

Best not mention you knew what you were doing.

Click here for more on Small Hive Beetle

Click here for more about the Native Irish Bee

Click here for updated list of Irish Native Honey Bee suppliers

Click  here for more about the Italian bee

Click here for the Buckfast bee

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Brother Adam (Karl Kehrle 1898-1996) came to Buckfast Abbey from Germany at the age of 12 and began to assist the beekeeper there.  In 1916, 30 of the 46 beehives at the Abbey were wiped out by Isle of Wight disease, now recognised as Acarine – a parasitic mite which moves in and occupies the windpipes of bees.

Brother Adam began to repopulate the Abbey’s hives using the existing bees which were a mixture of Italian or Italian x English dark native bees. He brought in more Italian bees and also travelled 100,000 miles across Europe and North Africa in search of desirable strains of bees to improve his ‘Buckfasts’ using an isolated mating station on Dartmoor.

What resulted was a hybrid bee which had many very good qualities. It seems likely that many of these qualities were due to the hybrid vigour of first generation crosses – and which cannot therefore be reliably passed on to subsequent generations. As a result, users of Buckfast bees must rely on breeders to requeen their bees at regular intervals otherwise their Buckfasts will simply out-cross with native stocks resulting in ‘mongrel bees’ which have, at best, mixed characteristics and are often very aggressive.  Even requeening is questionable – if you have to keep doing that something is wrong. So, ask yourself – are you a beekeeper or are you just someone who hasn’t  mastered the art of keeping bees?

Because of its mixed ancestry and assorted provenance the modern Buckfast bee is very variable in appearance so I’m uneasy about supplying a photo. In fact just about any bee with an orange band or two can be called a Buckfast but what on earth does that mean?

Below is a picture from Wikipedia of ‘Buckfast’ bees. They seem a bit light to me but anything is possible. However, more interesting is that two of the bees seen here are markedly darker than their sisters ( one at 12.00 and one at 8.00) which suggests that their mother, however ‘pure’ (and there is no such thing as pure Buckfast because at best Buckfast is a hybrid) has mated with a mixture of drones.

What any hybrid bee does not have in the real world is any reliability when bred from and subsequent generations will always be a mixed bag. Brother Adam was working in a different world, when Britain’s bees were thought to have been killed by Acarine and Chronic Bee Paralysis Virus (CBPV) also known as Isle of Wight Disease so it would have been much easier in those days to control the mating of queens. Such control is seldom possible here and now.

More recently it has come to light that the British native bee had not been wiped out at all but only seriously set back and efforts are now under way in parts of Britain to bring the native back. A difficult task given the number of imports of non-native and hybrid bees however, beekeepers in Cornwall have had some success and a native bee reserve has been created in the west country. Click here for more about that http://www.b4project.co.uk/

Also, and here’s interesting, the beekeeper currently running Brother Adam’s former apiary at Buckfast Abbey is breeding English native Apis mellifera mellifera again.

Because Buckfast bees reputedly build up a large colony early in the year they are thought by some to be the best ‘honey getters’. If you are one of those people, absorb and remember this sad fact – in Ireland only 2 years in any 10 can be classed as good summers, another 2 will be bloody awful summers and the remaining 6 will be the average shitty stuff.  Only in the 2 good years out of 10 will a Buckfast colony have a chance of out-performing the native bee; in the other 8 you will wish you had native bees.

Also bear in mind that honey bees are the result of a 350 million-year-long breeding programme called ‘Evolution by Natural Selection’.  Since the last ice age departed, they have undergone a further 12,000 years of fine-tuning during which time the native bee has survived and thrived despite every foul thing that fate and the climate has thrown at it. Do you, in your arrogance, seriously think you can better that?

Please also consider your neighbours. Tucked away in the landscape somewhere close to you could be a keeper of gentle, low-swarming native bees – the product of a breeding programmme honing the native and going back years. Your ill-considered colony of Buckfast bees will trash the work of decades. I ask you: – is that fair?

If, despite all this, you are still considering importing Buckfast bees, or buying from somebody else who imports Buckfast bees, or buying from somebody who claims to have ‘Irish Buckfast bees’ – remember this – out there Small Hive Beetle is waiting for someone just like you.  Click here for more on Small Hive Beetle.

Good article on the Buckfast bee here by Roger Patterson on Dave Cushman’s website http://www.dave-cushman.net/bee/buckfast.html

Click here for more about the Native Irish Bee

Click here for updated list of Irish Native Honey Bee suppliers

Click  here for more about the Italian bee

Click here for more about the Carniolan bee

Copyright © Beespoke.info, 2014. All Rights Reserved.

As you can see from this photo, borrowed from http://beeinformed.org, it is mainly light brown in colour and strikingly striped with dark brown on the abdomen.

As you would expect, it has its origins in Italy and is well adapted to the warm Mediterranean climate but it can also do well further north. The great beekeeper Johann Dzierzon – he of beespace fame imported them to Poland and worked them there for many years. They were also much imported to England and Ireland for a time as they do have many admirable qualities:

• In a good year they will bring in enormous crops of honey.
• They are very placid and easy to handle.
• They have a low swarming instinct.
• They also have a long proboscis which means they can take full advantage of the red clover which is a flower with a very deep throat.

They fare less well when the weather gets shitty though, and for a number of reasons:

• They are smaller, slimmer bees so less able to maintain body temperature.
• They bring in less propolis which makes them easier to work but in a cold, windy winter they might feel the draughts whistling round their ankles.
• They continue to breed very late in the year and as a result go into the winter with large colonies and many mouths to feed. Then they start to build up again very early – another drain on precious stores in the chilly north. They are renowned for the amount of stores they will go through in the winter.
• They drift and they rob;
• Small Hive Beetle has been found in Italy so before you go importing Italian bees or buying bees from someone who imports Italian bees – think about what else you might be importing. Click here for more on Small Hive Beetle;
• Also bear in mind – if you are outside Italy, you will only have Italian bees for one year – after that you will have mongrel bees because they will interbreed with your neighbour’s native bees and you will have to consider re-queening with more imported queens every year.
• And you will mess up your neighbour’s breeding programmes.

Cordovan Italians are a paler variant and as you can see from the picture below, again from beeinformed.org they are very beautiful and almost yellow.

I saw these once, they were working the blackberry, along with a number of their dark brown A.m.mellifera cousins, in south east England. I could hardly believe my eyes – they really are this pale.

Protection for Local Bees

In parts of Italy, breeders of Italian bees are tearing their hair out because people are importing foreign and totally inappropriate bees there and messing up the gene pool. In the Emilia Romagna region, the beekeepers have managed to declare a reserve for the Italian bee so it can be protected from extinction by hybridisation.

This is the same problem we have in Ireland and the Native Irish Honey Bee Society (NIHBS) is working towards similar protection for Apis mellifera mellifera.

Click here for more about the Native Irish Bee

Click here for updated list of Irish Native Honey Bee suppliers

Click here for the Grey bee – Apis mellifera carnica

Click here for the hybrid Buckfast bee

Copyright © Beespoke.info, 2014. All Rights Reserved.

How to recognise the Irish bee…

…these are some of my native Irish bees. Click the photo for a better view.

Here are some of the characteristics to watch out for when selecting breeding stocks:

• Dark brown, almost black in colour with no amber or yellow rings on the abdomen;
• Quite ‘burly’ in comparison to other races and hybrids – makes it easier to maintain body temperature;
• Narrow bands of sparse dark hair on 3 abdominal segments;
• Longer hairs than A.m.carnica and brown rather than grey;
• Thrifty overwinter with a longer broodless period;
• Slow spring build-up;
• Will work in drizzly weather;
• Tendency to supersede – less risky than swarming in bad climate;
• Small, compact brood nest;
• Short tongue reach – adapted for white rather than red clover;
• Much pollen stored all the way round the brood nest to sustain bees through long spells of shitty weather;
• Very fluid weather-reactive behaviour – will quickly throw out drones midsummer if weather is foul;
• Nosema resistance;
• Apiary vicinity mating – mating can be achieved even in vile weather. There is the risk of in-breeding though.

You’d be lucky to spot that last one but keep your eyes peeled.

The final arbiter is wing morphometry and a Cubital Index of 1.6-1.9.

Bee improvement links below:

Click here for more on Colony Assessment

Click here for more on Colony Appraisals

Click here for more on How to Improve your Bees

For more info on the Irish bee click here for Native Irish Honey Bee Society (NIHBS) website

Copyright © Beespoke.info, 2014. All Rights Reserved.

Look out for orange/brown pollen loads – along with the brighter orange from the snowdrops.

In fact, when the weather does warm up and the bees are active and bringing in that brown pollen it is worth going out to watch them working the gorse because the flower is specially designed to  make best use of the bees for pollination. Enjoy the strong coconut scent of the flowers while you’re at it.

The flowers each have a keel (lower part) and a banner (upper part). The banner is as the name suggests – a brightly coloured flag to lure insects. The keel is the boat-shaped lower part which offers itself as an insect landing pad. But all is not what it seems. The first bee to land on a freshly opened flower triggers the keel to burst apart releasing the spring-loaded reproductive paraphernalia which shoots forth like a boxing glove on a spring. The unsuspecting bee is hoisted into the air and a bunch of stamens, like a paint brush, dusts its abdomen with pollen.  At the same time, the style (female bit) jabs the bee in the belly and picks up gorse pollen from a previous floral heist. In fact here’s a photo I took – click it for a close up:

They say that the bees only get pollen from the gorse but if you watch them, they battle their way past the stamens and strive to get to the very throat of the flower. I think there must be a little smear of fresh nectar down there to draw them in – not enough for a crop of course but enough to act as a lure to a poor creature that’s struggled through winter on reconstituted and regurgitated honey.

Gorse is also under threat from the strangely named ‘Heritage Bill’ which came before the Seanad in 2017. If this bill is passed then among other acts of environmental vandalism we will have to watch out lovely gorse grubbed out and burned in full March bloom.

Click here for more about the Heritage Bill

Click here for more on gorse pollination

Copyright © Beespoke.info, 2014. All Rights Reserved.

For the bees, this fresh pollen and perhaps a little nectar heralds the beginning of a new year and may help nudge the queen into lay.

From the point of view of the snowdrops – the bees are welcome pollinators. Pollination is the transfer of pollen from the male parts of one flower to the female parts or another flower. Wind pollination is where male flowers or catkins of a plant, hazel for example,  release massive amounts of pollen into the air where it is carried on the wind to the female flowers. Insect pollination is where the same job is carried out by an insect. To attract insects, the flowers of such plants often exude nectar.

That’s the bare bones of it and that might be enough. For the nitty gritty though – read on…

The sex lives of plants can be confusing. Some plant species have individuals which are either male or female. Male plants have male flowers and female plants have female flowers. However, most plants are both male and female – they are hermaphrodytes. Either way, the flower is the reproductive organ. Some hermaphrodite plants, such as alder (Alnus glutinosus), have male flowers and female flowers. The male flowers are the familiar catkins and while the female flowers are smaller and purplish. If fertilised, the female flowers go on to form the little black alder cones which contain the seeds. I should add – so far as I know, bees don’t do alder.

Most hermaphrodite plants however, have flowers which contain both male and female organs. The female organ is the ovary which contains the ovules which in turn contain the female generative material. When fertilised it is the ovule which goes on to become a seed. The male organ is the stamen, the anther of which contains pollen grains.

Pollen grains contain male generative material and although it is their destiny to fertilise the ovules of a different plant, perhaps many miles away, they are obviously incapable of independent movement and depend instead on carriage either by insects or by the wind.

Pollen grains are microscopically tiny, they have a tough, highly durable and often richly ornamented coat and contain among other things – two nuclei – a tube nucleus and a generative nucleus. On the ripening of the pollen, the generative nucleus divides into two sperm nuclei and the anther bursts open to release the pollen to the wide world.

Some plants can self-pollinate – that is the ovule is receptive to pollen from the same plant. This is ‘self pollination’ and is generally considered to be a bad plan; it is better if they can be pollinated by pollen from another plant, so there are mechanisms in place to prevent selfing.

One such method is a sort of biochemical repulsion built in to the surface of the stigma which prevents the germination of all unsuitable pollen – a category which may include its own.

Fertilisation

The stigma is a sticky pad at the tip of the style designed to catch and hold grains of pollen. If the surface of the stigma is receptive to the pollen grain it will germinate, the tough coat rupturing to allow the growth of the pollen tube down between the cells of the style and guided towards the ovary by a chemical attractant – usually calcium. The growth of the pollen tube is controlled by the tube nucleus and the tube contains the two sperm nuclei. On reaching an unfertilised ovule the tip of the tube penetrates a tiny pore called a micropore and the two sperm nuclei are released into the ovule. One of the sperm nuclei fertilises the egg which goes on to develop into the seed embryo. The other nucleus somehow combines with two other nuclei and goes on to make the seed endosperm – a nutrient-rich ‘fodder’ which nourishes the growing embryo and will eventually fuel the tiny seedling that will eventually burst from a germinating seed.

Click the links below for photos of:

• Gorse pollination
• Hellebore
• Garden Heathers
• More on the booby-trap mechanics of gorse pollination

Glossary

Anther The part of the stamen producing the pollen grains.

Filament The stalk attaching the anther to the flower.

Carpel Female parts of a flower – stigma, style and ovary.

Generative nucleus Contains genetic information for use in fertilisation. On the ripening of a grain of pollen the generative nucleus divides to give two sperm nuclei.

Nectary Little ducts within the flower, which secrete nectar.

Ovary The ovary is the portion of a flower in which the ovules are contained and mature.

Ovule Structures that contain the female genetic information of what will become the seed of the plant.

Petal Little decorative flag unfurled to announce presence of ripe pollen and nectar to attract pollinators.

Pollen Male regenerative particle of flowering plant or conifer.

Pollen tube A structure which sprouts from a germinated pollen grain to convey the sperm nuclei down the style to the plant ovule.

Stamen Male reproductive organ of a plant consisting of the filament and the anther.

Stigma Receptive surface at tip of style to which pollen attaches and germinates.

Style Tube connecting stigma and ovary.

Tube nucleus One of the two nuclei in a pollen grain it contains the DNA needed to control the growth of the pollen tube.

Copyright © Beespoke.info, 2014. All Rights Reserved.