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| Nectar markers on nasturtium |
After Julia’s concise, clear and inspiring talk, were you out in the garden yesterday (in spite of the wind) examining your autumn flowers for their visual lure to attract pollinating bees? I certainly was.
Why do Bees Need Gardeners?
3/25 of UK’s Bumblebees are extinct & 7 species are critically endangered
Private gardens = vast acres of the UK
Bumblebees are much more numerous in suburbia than in farmland
< 2% of our flower rich, ‘unimproved’ grassland remains compared with 60 years ago
Whilst Julia’s professional life was initially in medicine, her passion was always about wildlife and bees in particular. (Julia’s father was the late Prof. Donald Piggott, plant ecologist who in the 1980s he was director of the Cambridge Botanic Garden.)
In 2010 Julia started her ‘not-for-profit’ business Bee Ed to provide information and education about pollinators, particularly bees. She and her team are based at Brigsteer Bee Reserve; a private wildlife reserve on the west-facing slope of the Lyth Valley in Cumbria. The eighteen acre reserve focusses on habitat provision for bees, harvest mice and glow worms. Hay meadows have been established in conjunction with Cumbria Wildlife Trust. In the autumn Shetland cattle graze these meadows.
We are all aware of that life sustaining symbiosis between flowering plants and bees. Bees rely on flowers for their food & flowers achieve optimal fertilisation for their species with the transfer of pollen by bees.
So it is no surprise to learn that following bee evolution there was an explosion of flowering plants (angiosperms) in the mid Cretaceous Period (120 – 100 million years ago). Fossilised bees in amber (which is fossilised tree resin) confirms their existence from this period!
How do flowering plants compete on market for bee attention? Well any early or late flowering plant must have better odds for bee pollination. Bees have a preference for pink/ purple/ blue flowers. Interestingly they see yellow as blue! Visual pollen and nectar markers may be present. Easily accessible pollen is a bonus (e.g. roses). With long tongues bees can access nectar nestled in trumpet shaped flowers. Scent is always attractive!
The British Isles became islands about 6 million years ago (as sea levels rose). As a result there has been less bee evolution and resultant species (due to isolation) compared to mainland Europe.
N.B. Honey Bees (Apis Mellifera) evolved in south east Asia ~ 7million years ago. Thus their descendants were not present during the formation of our Isles and so are NOT native in Britain. Four species of honey bee exist worldwide. We have only the European honey bee in Britain.
For clarification, in relation to bees:
Pollens
These are a vital source of food protein, fat & vitamins for bees and their young.
Nectar
This acts as a quick carbohydrate energy fix for bees so they can fly, build needs / ventilate hives etc. Honey bees use nectar to make honey.
Propolis
This is a ‘bee glue’ made by honey bees. It is made from floral oils & resins along with bee's own saliva and wax.
BUMBLE BEES
(Family – Apidae / Genus – Bombus)
In Britain there are 22/25 species in existence (7 of which are endangered). Like honey bees, they are cobiculate! I.e. the girls have sacs / ‘baskets’ on their hind legs for gathering pollen.
They have four wings (a larger fore wing & smaller hind wing) that are clear in appearance. Unlike honey bees they do not die once they string;
“Honeybees have a sting that has little barbs on it, which get caught in your skin when they sting you, and the unfortunate bee usually dies as a result because its body breaks in two when you swipe it away, leaving the sting still caught in your skin. Bumblebees have no barbs on their sting – it’s smooth – so they are able to sting and fly away. So the fact that they generally aren’t stinging people all the time is testament to their very placid natures!”
https://www.bumblebeeconservation.org
Bumblebees buzz pollinate. They cleverly ‘zizz / bizz’ at specific frequencies in different flowers causing mechanical release of pollen.
They like to nest in mouse holes or banks in sunny spots. Unlike the regular hexagonal structure of honeybee combs, bumblebee nests are more chaotic in structure! Are you a honeybee or bumblebee when it comes to looking after your home?
New queens emerge from hibernation & fly in February/ March looking for suitable nest sites. Once found they lay their eggs. Female workers emerge from fertilised eggs. They too join the marathon of nest building. Later drones emerge from unfertilised eggs. These drones mate with new queens. The new queens will hibernate later in the summer whilst the current years worker, queen and drones die. So early flowering plants (e.g. hellebores / snowdrops / aconites / willow catkins) are an essential food source for bee survival.
https://www.youtube.com/watch?v=1gysdWdZIBk
https://www.youtube.com/watch?v=NQuI6wB9TvY
[Be aware that Cuckoo Bees exist. Such bees have evolved the kleptoparasitic behaviour of laying their eggs in the nests of other bees. They appear similar to their pollen- collecting host bees; however their wings are more opaque or coffee coloured and they have sabre-like mandibles. Typically, they enter nests and lay their eggs in cells provisioned by the host bee. When the cuckoo bee larva hatches it consumes the host pollen ball & kills the host’s larvae!]
SOLITARY BEES
By definition they do not live in colonies. There are some 250 species in the UK. They make up approx 90% of the bee population. They include mason bees, leafcutters, mining bees, white faced bees, some carder bees and digger bees. Only the queens have a sting.
They prefer to be cooler so create nests in hollow reeds or twigs, in holes in wood or masonry, or most commonly in tunnels in the ground. These can be about one metre in length.
The female solitary bee typically creates a compartment (a ‘cell’) with an egg and some provisions for the resulting larva, then seals it off. A nest may consist of numerous cells and usually the last cells (those closer to the entrance) contain eggs that will become males. The adult solitary bee does not provide care for the brood once the egg is laid and usually dies after making the nests.
Solitary bees do not have pollen baskets. Because they have no baskets they are fabulous pollinators; losing pollen which is carried on their tummies. A single red mason bee is equivalent to 120 honeybees when it comes to pollination.
HOVER FLIES
Many hoverflies have evolved to resemble unpalatable or stinging insects like bees and wasps, while remaining harmless themselves, to deter would-be predators – a type of mimicry called Batesian mimicry. They have two wings.
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| Marmalade Hoverfly - Episyrphus Bulteatus |
Unlike honeybees and bumblebees that have 'tongues' for accessing and drinking nectar, most hoverflies have simple mouthparts with no tongue. This means they prefer to visit flowers with easily accessible nectar and pollen, so most tubular flowers like foxgloves, lavender and penstemons are off the menu.
A SUGGESTED ACTION PLAN for GARDENERS
Please create habitats in your garden for solitary & bumble bees
Provide Nests – remember they need to face the sun!
Leave some other natural nest & hibernation sites – compost heaps / ‘wild’ areas
Try to include single flowers plants e.g. cosmos
Include early & late flowering shrubs, perennial & annuals
Pink / Blue/ Purple / Yellow flowers are preferred by bees
Consider ‘No Mow May’
The horticultural industry is not yet as robustly regulated as agriculture in the avoidance of using neonictinoid pesticides.
She also recommended various books by Dave Goulson such as A Sting in the Tale.
Written by Trish R using various internet resources
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