Tuesday, 28 May 2013

Invasion of the bee snatchers - The life of cuckoo bumblebees



Southern cuckoo bumblebee (Bombus vestalis)
If you think there are only the hard-working bumblebees, busily collecting pollen and nectar all day, rearing their young and sacrificing themself for the well-being of their colony then read on as there is another bumblebee around, lazily sipping nectar all day and enslaving the workers of the hard-working bumblebees to rear their offspring.
These other bumblebees are aptly named cuckoo bumblebees and there are six species in the UK. All cuckoo bumblebee species resemble their host bumblebee species in appearance with often the same or a very similar colour pattern as the host species. 
 
The most common species of cuckoo bumblebee in southern and central England is the Southern cuckoo bee (Bombus vestalis). It`s host bumblebee species is the buff-tailed bumblebee (Bombus terrestris). Southern cuckoo bees are often found in gardens, parks and woodlands.
 
Host species of Bombus vestalis: Buff-tailed bumblebee (B. terrestris)

Cuckoo bumblebees often emerge quite late in spring when ordinary bumblebees have already established their colonies. They also have no caste system with queen, worker and males as in ordinary bumblebees but only have females and males. There are important differences between cuckoo bumblebees and ordinary bumblebees, some of them can help you to distinguish between the two types of bumblebee. 

1. Cuckoo bumblebees have no pollen baskets on the rear legs and you will never see a cuckoo  bumblebee loaded with pollen on the hind legs. 
2. They have also shortish tongues and are less hairy than ordinary bumblebees 
3. The body is much harder than the body of ordinary bumblebees which gives them an advantage in fights when taking over a bumblebee colony 
4. The wings are often dusky or dark in colour

A cuckoo bumblebee, good to see is the harder, less-hairy body

Cuckoo bumblebee searching for a bumblebee colony
It is thought that female cuckoo bumblebees find the host bumblebee colony by smell. They go into the colony and kill or subdue the queen and start laying their eggs. The workers are enslaved with pheromones and/or physical attacks and will rear the young of the cuckoo bumblebee now instead of the young of their queen. After the new generation of cuckoo bumblebees emerge they will leave the nest for mating and the females try to find new colonies to attack.
  
As cuckoo bumblebees only have to provide for themselves they seem to have a lot of time to just hang around and lazily sipping nectar from flowers now and again. They will never fly industriously from flower to flower as ordinary bumblebee workers will do on a sunny day.

Several cuckoo bumblebees on Wild marjoram flowers
Cuckoo bumblebees often seem to just hang around
 
So look out for the “lazy” bumblebees which do not seem to collect any pollen and just seem to hang around, it could be a cuckoo bumblebee.

Friday, 24 May 2013

Birds, newts and pollinators

The weather was not in our favour (again) this week; first we had a lack of sunshine and later a lack of warmth with temperatures resembling early March, not late May. So it is not surprising that we have not seen a lot of pollinators this week. Just a few tiny bumblebee workers, 3 solitary bees, no honeybees at all and some flies. We wonder if the pollinators are just hiding somewhere or if the wet summer last year and the cold spring this year have affected pollinator numbers in general.

So here is our week in pictures:

A nice flower-rich road verge in Whitley, but where are the pollinators?
This church in Southampton Street has a wildlife-friendly churchyard
A tiny Red-tailed bumblebee worker in the Laburnum flowers
Cranesbill with wallflower: a nice colour combination
Bombus pratorum (Early bumblebee) in a Ceanothus bush
Even Badger does not appreciate this cold weather
A blue tit waiting for us to go away so it can feed its chicks
And here it is finally flying to its nest where the chicks are calling
Andrena haemorrhoa sheltering in the grass
This beautiful garden pond was full of wildlife
A pond snail and some tadpoles
A Common newt male
Another Common newt
Ellen has found not one cat to cuddle ...
... but two. Here is the other one
This cat seemed to like our data sheets and did not want to move

Next week we will be starting the sampling of our perennial meadows in Reading. Fingers crossed for better weather and more pollinators. Watch this space to see how we are getting on.

Monday, 20 May 2013

A year in the life of an urban meadow

During 2012 the Urban Pollinators Project helped the city councils of Bristol, Reading, Leeds, and Edinburgh to establish urban meadows in their parks. The seed mixes for these meadows contain either annual plants (i.e. those that survive for a single growing season), or perennial plants (i.e. those that live for several years, regenerating from root-stock). This slideshow documents the rise and fall of annual plants at the Inch Park urban meadow in Edinburgh.


video

Friday, 17 May 2013

"What to do with an old shoe?"

The Yorkshire weather has not been in our favour this week - lots of dark clouds looming on the horizon...


But despite the cold, wind and rain, we managed to get out on a couple of dry days, sampling a variety of urban habitats across Leeds...

Pavement in Headingley
Car park in Holt Park (yes, there were a couple of dandelions!)
Verge in Meanwood (excellent quadrat placement despite the obstacles)
Allotment in Meanwood

Fieldwork is not just about counting flowers and hunting for pollinators - if you look around you, sometimes you will come across some unexpected delights.

Can you spot the real frog hiding under the violets in a garden pond?
Green-veined white butterfly (Pieris napi)
Cheeky cat inspecting our fieldwork kit
Beautiful beds in an allotment

And our favourite photo of the week (hence the blog post title)...

Old shoes needing a new lease of life? Why not add them to your allotment!

A typical fieldwork day in Reading

A typical fieldwork day in Reading normally starts with consulting the weather forecast. The weather forecast is really important for our fieldwork as we can only sample if temperatures are warm enough and if there is no rain. It looks sunny and reasonably warm with a threat of showers in the afternoon so we all gather in the fieldwork car and drive to the first field site which happens to be a cemetery today. The grass is quite short and flowers are few and far between so it will not take long to count the flowers and sample the pollinators.

Our Caversham cemetery pollinator transect

 Especially on cemeteries we often find plastic flowers from the graves in between the real flowers. Wonder if the bees get confused ;-).

A plastic flower from one of the graves nearby

Not far from our transect we find this nice area, planted with rosemary bushes and flowering trees (see below). 


And sure enough there are the bees we could not find in our transect nearby. The rosemary seems to be far more attractive to the bees than the daisies and buttercups in our transect. Not surprising really.

A honey bee visiting rosemary flowers
The next habitat we visit is a school playing field. The grass has just been cut so just a few daisies left for us and the bees (see below).


A little surprise awaits us in a little woodland area attached to the playing field. It is full of bluebells! What a nice sight. (see below). 


 But unfortunately no pollinators are around apart from a lonely bumblebee flying past.

Peter looks for pollinators in the bluebells

But there is something else which catches our interest. A huge badger set with several deep entrance tunnels.

One of the entrance tunnels of the badger set

And it is obviously an active badger set as we can find these big foot prints.

A badger foot print in the mud outside the entrance

We leave the school playing field and sample a pavement next. You might think pavements are just tarmac and devoid of life but look closer and you can see weeds growing out of cracks and garden plants encroaching on the pavement from the adjacent gardens.

A red dead nettle waiting for pollinators

After our lunch break we visit a park which has just been mown by the council. But to our delight they have left islands of  flowers uncut which not only looks nice but is also good for the pollinators. What a good idea! We would like to see these islands of flowers more often in parks and green spaces.

Lots of flowers thanks to a pollinator-friendly cutting regime

It is quite a nice and sunny day but we mostly find little black flies today, sitting in the daisies and dandelion flowers (not very exciting). We start to wonder where the bees are hiding. They are probably all in the rosemary flowers in the cemetery we visited earlier.
 
The most common pollinator today are little black flies

We visit a local nature reserve next and hope for a nice bluebell display. But what a disappointment, no bluebells and also no other flowers in our transect. But the woodland still looks nice with the fresh green leaves and the dappled sunshine (see below).


On our way back to the car we find a little patch of bluebells which look like our native bluebells (Hyacinthoides non-scripta). But not far, closer to the edge of the woodland, we find another patch of bluebells, this time the Spanish bluebell (Hyacinthoides hispanica). We also find some bluebell hybrids nearby. This is what happens quite a lot now, Spanish bluebells are planted in gardens because they are bigger and showier. They escape into natural habitats and hybridise with the native bluebells which is not really good. If you want to plant bluebells in your garden please only plant the native bluebell and not the Spanish bluebell.

Native bluebell (Hyacinthoides non-scripta)

And finally we find a pollinator in a little clearing,  a Speckled wood basking on a bramble leaf in the sunshine. So there are pollinators in this woodland after all.

A speckled wood butterfly

A look  at the sky confirms, showers are building up. So we hope to visit one more site before we are heading back to the University. Our last field site for today will be the BBC Berkshire car park in Caversham.

Our fieldwork car in front of the BBC Berkshire entrance

Our transect across the car park yields no flowers and no pollinators (see below).


But as we walk past the main entrance we see some flowering Berberis shrubs which attract quite a lot of pollinators, mainly bumblebees. We can count 4 different species of bumblebees, Red-tailed  bumblebee (Bombus lapidarius), Common carder-bee (Bombus pascuorum), Buff/White-tailed bumblebee (Bombus terrestris/lucorum) and the cuckoo bumblebee Bombus vestalis or B. bohemicus (they are very difficult to distinguish from each other). The cuckoo bumblebee is very interesting as it takes over the nest of Buff/White-tailed bumblebees, kills the queen and lets the workers raise its offspring. Not a really nice fate for the Buff/White-tailed bumblebees.

A cuckoo bumblebee (Bombus vestalis or B. bohemicus)
A buff/white-tailed bumblebee worker at Berberis flowers

We watch the bumblebees for a while but it is time to go now, so we get in the car and head back to University. We have only caught 6 pollinators today (mostly little black flies) but have seen lots of other interesting things including bluebells, a badger set and a cuckoo bumblebee. So all in all a successful day.