Friday, 30 December 2016

Review of "Universal : A guide to the Cosmos" by Brian Cox and Jeff Forshaw

Just finished reading Universal : A guide to the Cosmos by Brian Cox and Jeff Forshaw and thought it might be worth sharing a few thoughts about this very interesting book.

Universal aims to take the reader on a journey that shows how, from very simple beginnings, we can use observations of the world around us to answer surprisingly big questions such as "How much does the earth weigh?" and "How far away are stars?

To take one example, Universal mentions the experiment performed by Lord Rayleigh to give an upper limit to the size of an atom. NSB had a try at it and you can too - all you need is some cooking oil, a paperclip, a ruler and a bowl of water.

The oil drop NSB used to estimate the maximum size of an atom

Equally simply, if given a suitable landmark off the coast and using a little geometry [developed by Al-Biruni], one can hazard a guess as to the size of the earth - something that the book describes using the geography of from Ogmore-on-Sea.

NSB, living far from the coast, had a bash at replicating the experiment using suitable seaside photographs on the Internet, specifically this image of Keros taken from Koufonissia.

Universal goes on to look at the distance to the stars and the size of the universe, taking time to gently explain to the reader how data was corroborated at each step

Indeed, if you are an amateur astronomer with a small telescope in your garden and some photographic equipment; and make an assumption or two; you can show that the universe is expanding, and at what approximate rate!

NGC 4414, about 60million light years away
(The Hubble Heritage Team)

An important point that Universal makes is explaining how science works and how our confidence in measurements is strengthened when they can be determined via different techniques - for example, there is confidence in the age of the solar system being ~4.6billion years because estimates of the age of the sun (using knowledge about nuclear fusion and the heat received by the earth) and estimates of the age of the earth (using knowledge about radioactive decay in rocks) both give values around this figure. As the book comments:
"It is easy to cook up a scenario, however fanciful, that casts doubt on some measurement or other. But it is usually extremely difficult to argue for a radical change in one area without making large parts of the whole interlinked [scientific] edifice inconsistent"

The book also mentions the words of Richard Feynman:
"In general, we look for a new law by the following process: First we guess it; then we compute the consequences of the guess to see what would be implied if this law that we guessed is right; then we compare the result of the computation to nature, with experiment or experience, compare it directly with observation, to see if it works. If it disagrees with experiment, it is wrong. In that simple statement is the key to science. It does not make any difference how beautiful your guess is, it does not make any difference how smart you are, who made the guess, or what his name is — if it disagrees with experiment, it is wrong.”

Another point that is made is how hard, and for how long, people have worked to obtain key pieces of information, such as the distance from the Earth to the Sun.

Towards the end of the book, having taken the reader on an incredible journey through space, time (and space-time), Cosmos ponders why the universe is the way it is, so finely tuned to allow the formation of suns, planets, water and us. The book also explores theoretical possibilities such as that of the "multiverse"

Universal : A Guide to the Cosmos

Related NSB Stuff:
Fee- An Autobiography
Curiosity, Twitter and the British Connection
Interview with Prof Aragon-Salamanca
Interview with Prof Chris Lintott
Some background to the Space Shuttle
Lecture by Chris Lintott on 2011 Astronomy highlights

Wednesday, 14 December 2016

Making Science Public in 2016

NSB is a fan of the "Making Science Public" blog at the University of Nottingham and thought it might be nice to highlight some of the articles that have particularly caught NSB's attention over the last year...

Antibiotic resitance
January saw a post that talked about the hot topic of antibiotic resistance. It turns out that this is far from a new concern, with Alexander Fleming voicing concerns in 1945, and by 1969 there were calls for restictions to be placed on the use of antibiotics in animal feed.

The Trough of Disappointment
February was the month that NSB learnt about the Hype Cycle and the Trough of Disappointment.

The Hype Curve

The Impact Agenda
A guest post by Prof John Holmwood warned of dangers with the "Impact Agenda", commenting that:
"Where an earlier tenet of research policy.... was that there should be no public funding of research for private beneficiaries, that has been inverted such that there should be no public funding unless there is a direct, identifiable user."

Scientific Authority
March saw a post about the relationship between scientists, politicians and the public - with a number of interesting links, including a Demos article that described how badly the relationship between these groups fell apart in the wake of the BSE fiasco in the early 1990's.

John Gummer - A cautionary tale.

Another reference was to an article by David Demeritt who commmented that :

“The proper response to public doubts is not to increase the public’s technical knowledge about and therefore belief in the scientific facts of global warming. Rather, it should be to increase public understanding of and therefore trust in the social process through which those facts are scientifically determined. Science does not offer the final word, and its public authority should not be based on the myth that it does, because such an understanding of science ignores the ongoing process of organized skepticism that is, in fact, the secret of its epistemic success.Instead scientific knowledge should be presented more conditionally as the best that we can do for the moment. Though perhaps less authoritative, such a reflexive understanding of science in the making provides an answer to the climate skeptics and their attempts to refute global warming as merely a social construction.”


Also worth looking at this related paper on public perception of risk.

Crowdfunding Science
NSB had no idea there were crowdfunding sites for science projects, but it seems they are indeed a thing - see here

Worth mentioning, however, that another way to support science is to donate to research charities

Post-Truth
Some comments on the "Post-Truth" world we now seem to live in, including this comment by Alice Bell :
“We pool our resources to allow a few people to cut themselves off and become experts in particular subjects. We do this so that they might feed back their knowledge and we can, collectively, try to make a better world.”

Related Content
Communicating Risks of Earthquakes
Rick Borchelt on Science Communication
What would the Public want?

Image Sources
Hype Cycle, Burger

Saturday, 10 December 2016

The difference between NUMBERS and RATES

Was talking to No3 Son recently about a piece of science homework in which he had to chart and comment on 2012-2014 cancer statistics. The data was a great example of how the NUMBER of cases can give a very different picture to the RATE of cases. Looking at the NUMBERS chart (red) one might think that 70-79 is where the biggest danger lies - but this may be misleading as the graph shows the number of cases not the rate (e.g. per 100,000 people). Using 2011 census data from Wikipedia, one can work out the RATE of cases per 100,000 people (blue chart). It is clearly different and now you can see that the older you are the more chance you have of getting cancer.

2012-2014 Cancer Data

Cancer NUMBERS

Cancer RATES

Saturday, 26 November 2016

Citius, Altius, Fortius - Hervé Morvan's inaugural lecture

NSB was chuffed to find that the recent UoN Inaugural Lecture by Professor Hervé Morvan, Director of the Institute for Aerospace Technology and Head of Gas Turbine and Transmissions Research Centre has been posted onto YouTube. This post is based on the lecture, with some additional bloggage and linkage.

Prof Morvan began by explaining that the translation of the lecture title was the well known Olympic slogan "Faster, Higher, Stronger" before moving on to talk a little about Britany, the French region he grew up in. The Prof commented that he had a passion for comic books and illustrated novels and that, unlike fellow Gaul Obelix, he "doesn't need a potion to get energised".

Obelix and his Menhir

Prof Morvan started his UoN career applying Fluid Dynamics theory to hydraulic applications such as dams, water systems etc. An early collaborations with Donald Knight at Birmingham Uni on the "roughness" of river channels won the Schoemaker Award from the IAHR Hydraulics organisation. You can download the paper here and read more about this area of research at this UoN Page.

Rough flow...

...Smooth flow !

The Prof also worked on models of cataclysmic prehistoric floods in the Altai region of Siberia, where flows were in the region of 6-9million m3/sec, some 10,000 times as great as flows in a normal river. You can read the paper here.

Gigantic current ripples in Kuray Basin, Altai, Russia, as though a huge amount of fast moving water has flowed over this surface

Prof Morvan became involved with Rolls Royce around 2006, starting in hydraulics, then holding a RAEng industrial fellowship in 2008 before working at Rolls Royce for one day a week as a specialist until the responsibilities of the IAT and other efforts meant that Prof Morvan had to give up his Rolls Royce position.

Much of Prof Morvans work with Rolls Royce has been in the area of ensuring effective fluid cooling of the engine core, bearings and other areas. Computational Fluid Dynamics (CFD) models were important because should the fluid flow had dead spots, or did not reach certain areas, then there was a risk that these might overheat and fail.

To give a feeling for what a Rolls Royce Trent aeroengine has to deal with, Prof Morvan pointed out that a Rolls Royce Trent jet engine would typically take in 1.4 tonnnes of air per second.

The front fan sucks in the air, the turbine squeezes it, burns it then blows it out the back.
Turbines at the rear are spun by the exiting gas and power the fan and turbine at the front of the engine via the central shaft.

Alongside his Rolls Royce work, Prof Morvan became involved in a very different project in the lead up to the 2008 Olympics. This project involved helping Speedo to develop their LZR low-drag swim costumes and built on previous efforts started by the late aerospace engineer Barry Bixler, who became became interested in the subject when his daughter took up swimming. The costumes work use a number of techniques to reduce drag, including a foam layer that makes the swimmer more boyant and the use of elasticated panels that squeeze the body and reduce cross-section. The project involved analysing the swimming actions and shape of hundreds of swimmers, and then using CFD to see how the swimmers shape could be modified to reduce water resistance. More information can be found here, here, and here. Some of the Speedo patents are GB2444803 and GB2444804

Computer model of the Speedo LZR 

Looking at how technology has progressed, the Prof pointed out that fuel requirement per passenger was down some 70% since the days of the Comet, while engine noise has been reduced by some 70% in the same time period. The aero industry was not resting on its laurels, however, and has committed to significant further efficiency improvements, such as the roadmap by IATA and others to achieve a "50% reduction of the world air transport’s carbon footprint by 2050". These savings are hopefully going to be delivered by projects such as "Clean Sky 2" and "Horizon2020".

The Rolls-Royce composite carbon/titanium (CTi) fan blade under flight test as part of "Clean Sky"

A significant part of the talk gave an overview of how Prof Morvan and his team had spent several years researching fluid dynamics to improve their CFD models so that they do a better job of simulating the complex oil flow in engine areas such as bearing chambers. The challenge in this area is significant, as the model needs to replicate both thin films and pools of fluid, as well as how the oil interacts with high speed rotating machinery such as bearings.

You can read more about the (surprisingly long) history of fluid dynamics studies in this presentation by Andre Bakker. And there is an easy to understand comparison of computational and experimental fluid flow analysis techniques in this set of slides by Dmitri Kuzmin at Dortmund University.

Engine core cooling is vital, not least because the engine core is becoming more compact and the turbomachinery working at higher speeds and higher pressures and temperatures. The simulations Prof Morvan's team does are one step in the direction of right-first time digital design, which reduces the need for testing and shortens the design process, which is key to ensuring that Rolls Royce engines remain competitive. You can read one of Prof Morvan's latest papers, on the modelling of oil droplets in a bearing cage, here.

CFD simulation of two liquids with differing densities interacting

Prof Morvan then went on to talk about future developments, which he placed in two categories:

Firstly, there are future engine architectures, such as the Rolls Royce Ultrafan™ Engine, scheduled for introduction in 2025 (which means engine testing has to start in the next few years!). This is a geared design, which allows the bypass fan to operate at a different speed to the core. This, in turn, gives the core freedom to run smaller, faster, hotter and more efficiently. The engine aims to offer at least 25 per cent improvement in fuel burn and emissions against the current baseline. Prof Morvans team is using their transmission and modelling skills on this project.

Another engine architecture being considered is the "Open Rotor" concept (see also here), although this had a number of technical and certification issues to be overcome (in particular, how would a broken rotor be contained so that it did not hit the fuselage).

Geared fan in the forthcoming Ultrafan™

Rolls Royce Open Rotor design

The second area of future development related to the use of electric or part electric propulsion systems. Initial steps are being taken with the Airbus E-fan aircraft whose ducted fans are driven solely by battery power.

While E-fan has shown that electric flight is possible, it is not a revolutionary technology. Prof Morvan believes that the IAT has great ambition and capability for the next stages with its G2TRC and PEMC groups. Radical changes are likely with the progressive marriage of mechanical and electrical systems and a direction of travel towards all electric.

At present just a few percent of aerospace research effort is directed at electric propulsion but this is bound to grow ten fold and Prof Morvan's group intends to be a key player both nationally and internationally.

An Economist article describes how so-called "Distributed Electrical Power" architectures could dramatically change many aspects of aircraft design, efficiency and capability.

To see what is happening in the US, worth having a look a couple of NASA presentations (see here and here) - some remarkable stuff on the drawing board.

In Europe, Airbus and Rolls Royce are working on the "E-Thrust" project, which is a design study for a hybrid powered airliner.

With electrification, cooling remains a key concern (together with reliability), so the IAT expects to be contributing here also.

Airbus E-fan

Airbus E-Thrust hybrid airliner

NASA X46

Prof Morvan closed out the talk by commenting on forthcoming projects and the industrial infrastructure in the Midlands, commenting that:
"... the Midlands is doing very well, it's a good place [for centres like the ATI] and that is because universities are working with industry..."
The Prof commented that the region was the premier destination for CleanSky funding - with some 32milllion Euros coming into the area and added that the "Midlands Engine for Growth" was another positive factor in the areas favour.

These regional investments benefit not just the University of Nottingham, but also Loughborough, Warwick, Birmingham, Aston and Leicester Universities as well.

One nice touch that the Prof added to the talk was to randomly pop up images of famous aircraft and ask the audience, rhetorically, to identify them. These included the Dassault Super Etendard, legendary pilot Chuck Yeager, stills from "The Right Stuff" and the Mirage 2000 which Prof Morvan described as "the most beautiful aircraft, in my view, ever made".

The Right Stuff 

Prof Morvan has a blog at the University of Nottingham. In addition, you can read more about Prof Morvan's life and comments on industry in this rather nice interview. The following comments are taken from the interview and seem like a good way to close out this post:

"Make the most of any opportunity that is given to you. In a university, opportunities exist for initiative-takers, so go after things and make a difference; people will notice and you will go places. I have learnt from Rolls-Royce that as long as you deliver and can be trusted, your ideas can have a real future and make a difference.

Be flexible and adaptable, too. I wasn’t necessarily dead-set on solving a particular fluids problem when I arrived at Nottingham (I started on hydraulics in Civil Engineering!); I had fluid skills; I was very interested in aerospace; in energy and I made these skills available to the sectors, delivered for people, proved myself in the process I think and it has paid back. "


Related Content
Soyuz Soyuz TMA-15M / ISS 42 Launch
Apollo Programme Manuals
Interview with Prof Farouk El-Baz
Smithsonian Air and Space Museum
Background to the Space Shuttle

Image Sources
Obelix, Instability, Rough River, Smooth River, Altai, LZR, Jet Engine, Blade, Ultrafan, Open Rotor, E-fan, The Right Stuff, X57

Thursday, 24 November 2016

Talk : Ground Shakers and Feathered Flyers

Another informative guest post from @GavSquires (with linkage from NSB):

Between July and October 2017, a dinosaur exhibition comes to Wollaton Hall - "Ground Shakers and Feathered Flyers" Dr Wang Qi and Dr Adam Smith give a bonus talk at September's Skeptics in the Pub event to tell us all about it.

Wollaton Hall was built in 1588 and since 1926 it has been home of the Nottingham Natural History Museum. With over 40,000 fossils it is one of the largest provincial museums in the country. Next year, the Great Hall and Willoughby Hall will be home to some large dinosaurs and some scientifically important ones. The specimens are coming over from the IVPP in China and have been personally chosen by Wang and Adam. For some, it will be the first time that anybody outside of China has seen them.

Dinosaurs of China, coming to Nottingham

There is going to be a 3D mounted skeleton of a Gigantoraptor, so not the real bones but it is anatomically accurate. At 8 metres long by 4.5 metres high, this was the largest feathered dinosaur. The Microraptor was a much smaller species, which had feathers on its forearms and legs. These are genuine fossils, extracted in China and is actually a holotype specimen (the original example that was used when the species was formally described) With these, it's hoped that people's perceptions of what a dinosaur is.

Giganoraptor

Artist impression of a Microraptor
PNSO Artist: Zhao Chuang

Other specimens coming to Nottingham include the Sinraptor, which is not feathered. It's 7 meters long and is essentially a Chinese version of a Tyrannosaurus Rex. The Linheraptor specimens aren't real fossils but are flat casts that are then painted up. These dinosaurs were related the Velociraptor but were bigger (although not as big as the Velociraptors in Jurassic Park)

Artist impression of a Linheraptor

The Mei Long is a "sleeping dragon". At only 20 centimetres long, it is one of the smallest dinosaurs and they exhibit the same behaviour as sleeping birds. Guanlong was a meat eating dinosaur and was one of the early ancestors of Tyrannosaurus Rex. It had an unusual crest on its head that looked like a crown.

Mei Long Fossil

Artist impression of Mei Long

The north border of China, near the Mongolian border, was home to the Gigantoraptor. This area is now so well known for dinosaur discoveries that even the highways have sculptures of dinosaurs on them. In 2005, Tan Lin discovered the Gigantoraptor but only 50% of a complete skeleton has been found.

Later, a Japanese TV crew went to the area to film a documentary about finding Gigantoraptor. They set up a shot where they were pretending to discover it for the first time. They thought that they would be able to find the bone of something that had seen before but they actually found something brand new. The TV crew had to be escorted away so that this completely new discovery could be investigated.

The whole region is a goldmine of findings from the Cretaceous Period. Just south of the Gigantoraptor site, there are even more feathered raptors to be found. In fact there are so many samples and they are so easy to get hold of that local collectors could easily open their own museums!

For more information about the exhibit at Wollaton Hall and to buy tickets, visit the website: www.dinosaursofchina.co.uk

[And to read more about the evolution of feathers in dinosaurs, get clicky here, here, here and here].

Related Content
The World in Ten Fossils, Fee- An autobiography

Image Sources
Giganoraptor, Microraptor, Linheraptor, Mei Long, Mei Long impression

Sunday, 13 November 2016

Great Central Railway 47292 and 8274

Sundays often sees the "Great Central Railway - Nottingham" heritage railway bringing one or more of its fleet out for a trip along the line. The line's engine sheds are located in Ruddington. NSB occasionally takes pictures of trains that are and has been digging into their history...

47292 Class 47 Diesel

Class 47  Diesel Engine 47292

Designed by Brush Traction, a total of 512 Class 47s were built in the 1960s at Crewe and the Brush Loughborough works.

They were powered by 12 cyclinder Suzler diesel engines manufactured by Vickers at Barrow in Furness (perhaps using some of that famous Lanarkshire Steel?). According to Chris Brooks, Vickers made some 1500 engines over a five year period, representing one of Suzlers largest single contracts.

There are currently some 32 Class 47's operating on various heritage railways in the UK.

LMS Stanier Class 8F Steam engine 8274

LMS Stanier Class 8F Steam Engine 8274

Some 852 of the Class 8F engines were built between 1935 and 1946 for freight use. Many saw use across the British Commonwealth during WW2.

The Class 8F's were built in a number of locations, with 8274 being produced by the North British Locomotive Company in Glasgow - at the time the largest locomotive manufacturing company in Europe and the British Empire. The company sold engines to customers around the world, including Canada, Argentina, Spain, Angola, Palestine and China. (Again, on wonders whether the engines were made with local Lanarkshire Steel.)

8274 was one of 25 exported as kits to Turkey in 1940 (although 7 were lost at sea en route), returned to UK in 1989 and then restored to operational condition. One of its sister engines can be seen in the Çamlık Railway Museum in Turkey (see also here)

Interesting to see the role that a single scrapyard in South Wales had in providing many of the engines for the Steam Heritage industry that sprang up following.

Image Sources
Full image of 47292 Related Content
Train Manufacture in Derby
History of Coal Mining in the East Midlands

Sunday, 6 November 2016

Social Science Show - Reality and Image

Interesting show at Wollaton Hall recently, as part of the ESRC's "Festival of Social Science". A few images and notes below...

Part of the show looked at how the mind reacts when visual inputs are messed about with. For example, some special goggles were on hand that shifted a persons vision so that what appeared to be straight ahead was actually slightly to one side.

An one might expect, if (while wearing the goggles) you try to touch a pencil held at arms length your finger will miss the target - but after a few goes your mind learns to compensate and ones aim gets better.

But take the goggles off and you start missing the pencil again until your mind recalibrates again

Image Shifting Goggles

Another section looked at the photographs and what makes them look "real", this has resulted in a photographic manipulation technique called "Fovograph" which aims to replicate the way people look at a scene - with higher resolution at the centre and with slight distortion at the sides. You can find out more about the www.fovography.com at the Cardiff Metropolitan University website, which describes the project thusly:

"The main purpose of Fovolab is to better understand the nature of visual experience and how to depict it. We do this by combining knowledge and methods from the art, sciences and humanities, each of which has a role to play in solving the complex issues involved.

We have developed a process called Fovography that overcomes these limitations. It allows us to capture the full field of view (hence the prefix ‘fov’) and present it on a flat surface in a way that appears natural to human perceptions. Moreover, because we represent the human visual field in a natural way the resulting images appear to have much more breadth and much more depth than conventional images. This means we can create, in effect, 3D visual experiences without glasses, goggles, or expensive screens."


Fovography didn't really work for NSB because what NSB prioritises in an image is resolution, focus and being distortion free. But looking at what other people thought of the images suggests that this was a minority view.

You can vote on how the images look yourself at a survey page at Cardiff University.

Related to this were some images by artist Robert Pepperell who attempted to produce drawings that showed what he was actually seeing - complete with lack of focus in peripheral vision - in comparison to a photo of the scene.

Image of room and Pepperells's perception of it - Interesting stuff

There was also an interesting section where people, young and old, could take part in a "Stroop Test" to see how capable their mind was of ignoring background audio when asked to identify the colour of blocks appearing on a screen (so, for example, avoiding identifying a green block as blue just because a voice through the headphones says "blue".

The aim of the project was to see whether the ability to ignore distractions changes with age, and whether the effect is greater with written or spoken distractions. Rebeccca Hirst, researcher on the project explained to NSB how this was an interesting area of research, with many factors in play - for example, children tend to be rather susceptible to spoken distractions, while adults may have some ability (through experience) to "tune out" some distractions. Rebecca also explained how the project took care to account for variables such as the decline in hearing ability with ageing.

The project is supervised by Harriet Allen whose description of the project comments that:

" I research the links between vision, attention and ageing. How does an instruction to attend to an item get translated into the visual system? How do changes in goals (for example, to do with food, or clinical state) change this? Attention might enhance vision in a number of ways. Attention might simply speed up how quickly we respond to a stimulus, it might make us more likely accept that a stimulus is present, it might reduce the noise associated with the stimulus or increase the signal perceived from the stimulus...

...As well as being interested in the effects of attention on vision, I’m interested in how these change with age. If we try to look for our friend arriving at the station, we could enhance the representation of any new person arriving on the scene, we could suppress the representations of people and things already visible, or both."


You can read more about this subject in a paper by Maria J S Guerreiro et al entitled "The role of sensory modality in age-related distraction: a critical review and a renewed view."

Do you want to try the Stroop Test?

Elsewhere there a display looking at stereo vision, which included "Magic Eye" images and a pair of glasses (a "Wheatstone Stereoscope") that had mirrors which gave one vision as though your eyes were further apart - this had the effect of increasing perception of depth of field.

A paper by Jenny Read fron the University of Newcastle entitled "What is stereoscopic vision good for?" was also available, and is well worth reading.

Related Content
Talk : Cochlear Ear Implants
Talk : The Flavour of Food
Science in the Park 2013 - Pt1

Monday, 10 October 2016

The National Pollinator Strategy

In recent years there has been increasing concern about bee numbers, primarily in the context of their role as pollinators of crops.

The media, (see also here) has focussed on concerns regarding Neonicotinoids, but other factors such as bee habitat loss are also factors. It is also worth noting that in some areas there has been a switch away from wind pollinated crops such as wheat, to insect pollinated crops such as oilseed rape.

Worth reading this article to give context to the "third of hives lost" comments that are sometimes bandied about.

Neonicotinoids are currently banned in the EU (something the UK voted against) whilst a risk evaluation is undertaken. The ban was imposed based on research in a 2013 European Food Safety Authority study that looked at the neonicotinoid clothianidin and found, whilst there were significant data gaps, that:

"A high acute risk to honey bees was identified from exposure via dust drift for the seed treatment uses in maize, oilseed rape and cereals. A high acute risk was also identified from exposure via residues in nectar and/or pollen for the uses in oilseed rape."


It is noticeable that UK supermarkets are nervous about the use of Neonicotinoids in their supply chains, as described in this Bloomberg article

On the other hand, the National Farmers Union feels that the case against Neonicotinoids - in actual farming situations - has not been made and that the largest losses in bee numbers happened well before Neonicotinoids were introduced.

One manifestation of bee loss is in increased levels of "Colony Collapse Disorder" seen in many countries since 2006.

In 2014, the UK government, in collaboration with stakeholders ranging from the Bee Farmers Association to the National Farmers Union to Waitrose, developed a "National Pollinator Strategy".

This 10 year strategy has a vision to:

"..see pollinators thrive, so they can carry out their essential service to people of pollinating flowers and crops, while providing other benefits for our native plants,the wider environment, food production and all of us."


The report states that pollinators face many pressures, including habitat loss; pests and diseases; extreme weather; competition from invasive species; climate change; use of some pesticides.

And goes on to add that :

"The independent scientific review of the published evidence commissioned by Defra in 2013 identified the loss of flower-rich habitat as the likely primary cause of the recorded decline in diversity of wild bees and other pollinating insects. Loss of these habitats is associated with past intensification of agriculture, urbanisation and industrial development...Pests and pathogens were identified as the key threats to managed honey bees, although past loss of flower-rich habitat was also considered important. The reviewers identified other factors such as invasive species or climate change as additional pressures to pollinator populations, and pointed out that these pressures interact in a way that we do not fully understand."


In terms of actual policies and actions, some examples are shown below :

Working with farmers
5 simple actions: Grow more flowers, shrubs and trees that provide pollen and nectar; leave patches of land to grow wild; cut grass less often; avoid disturbing or destroying nests; think carefully about whether to use pesticides.

Working in cities
Ensuring good practice to help pollinators through initiatives with a wide range of organisations and professional networks including managers of public and amenity spaces, utility and transport companies, brownfield site managers, local authorities, developers and planners.

Encouraging the public to take action in their gardens, allotments, window boxes and balconies to make them pollinator-friendly or through other opportunities such as community gardening and volunteering on nature reserves.

Improving Bee colony resiliance
Working to improve beekeepers’ husbandry and management practices to strengthen the resilience of bee colonies.

Raising Awareness
Disseminating further advice to a wide range of land owners, managers and gardeners as part of Bees’ Needs.
Improving the sharing of knowledge and evidence between scientists, conservation practitioners and NGOs.

Better Data
Developing a sustainable long-term monitoring programme so we better understand their status, the causes of any declines and where our actions will have most effect.

Better Pest Control
Aiming to ensure low pesticide input and/or targeted use to minimise risks to the environment.

So, two years in, how is the strategy going?

NSB asked the following of Bee Farmers Association:

"I've been reading the National Pollinator Strategy (as research for a blog post) and noticed the Bee Farmers Association as being one of the organisation working with DEFRA on that project.

Just wanted to ask how you think the strategy is going, two years in, and whether the decline in UK bee numbers is being halted."

The NFU has a number of articles on bee numbers, with this and this perhaps most relevant. The articles describe how over 7,000 acres of seed mixes for bees have been voluntarily planted by farmers to enhance land lying fallow.

Also sent an email to Waitrose :

"I've been reading the National Pollinator Strategy (as research for a blog post) and noticed Waitrose as being one of the organisation working with DEFRA on that project.

Just wanted to ask how you think the strategy is going, two years in, and whether the decline in UK bee numbers is being halted. Also, what is your view on Neonicotinoids - will you eliminate them from your supply chain or do you share the NFU's view that the link between them and bee population decline is unproven?"



European Honey Bee doing its thing.

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Talk : Reproduction in Bedbugs
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Talk : Dung Beetles and Drugs
Image Sources
Bee

Wednesday, 24 August 2016

Ben Nevis

Having been blessed with the chance, and the health, to walk up Mount Snowdon and Scafell Pike several years ago, NSB has long wanted to make it to the top of Ben Nevis, the third of the "Three Peaks". The chance came around recently on a trip to Scotland, and NSB was doubly blessed by very good (i.e. clear) weather. Below are some pictures but, before that, lets have a look at how Ben Nevis was formed.

Ben Nevis is the tallest mountain in the UK, at 1344m, and is located next to Fort William in the Scottish Highlands.

The mountains in this area were formed some 400 million years ago during the Caledonian Orogeny. At this time the Iapetus ocean was closed by the collision of the continents of Avalonia, Laurentia and Baltica. The images below from the BGS show how the upper and lower parts of the UK mainland were joined together during this process. As the ocean closed, there was a great deal of volcanic activity at the subduction zones at the ocean edges. This volcanic activity (which is similar to the volcanic activity on the western seaboard of South America currently) is what gave rise to the volcanic rocks in the Lake District and the Highlands of Scotland.

 

 

Also here is a nice video explaining how Ben Nevis was formed (suggest skipping the first minute or so though).

The so-called "suture" line can actually be seen in the Isle of Man, as shown below.

Standing on two different tectonic plates

The rocks at top and left formed in Laurentia (which contained Scotland) but the rocks at lower right formed in Avalonia (which contained England).

Also well worth reading this vividly written BBC article on the volcanic history of the UK

Since its formation, Ben Nevis has been eroded down very significantly, as shown below - walking to the peak is now a journey through the interior of a volcano!

Schematic showing how Ben Nevis formed and was then eroded to it's current shape
Copyright Royal Geographical Society

Much of that erosion was caused by glaciers during past ice ages, when the Ben Nevis range might have looked something like this image from Greenland.

During the Ice Age,  the Ben Nevis area might have looked something like this

With that introduction out of the way, here are a few pictures of the walk up to the Ben Nevis peak.

Starting out,  100-200m up, looking along Glen Nevis

By  Lochan Meall an t-Suidhe - the "Half Way Lake" about 580m up

Looking back at the lake from about 900m up.

The top part of Ben Nevis is a "blockfield" of angular broken rocks. This is believed to have formed during the last iceage when the majority of the mountain was covered in a glacier leaving the exposed top vulnerable to erosion by freeze-thaw action.

At around 1200m and no, that isn't the top.

View  north just before reaching the top,
sheer drops if you drift off course in fog

Incredible view from the top 1340m

Image Sources
All NSB own except Isle of Man, Greenland , Iapetus, Schematic

Royal Geographical Society (with the Institute of British Geographers) (schematic)

Saturday, 25 June 2016

Mike's Bees!

Mike, a work colleague of NSB, has recently undertaken a course in Beekeeping and with a view to having his own hive. Thought that it might be worth sharing Mike's Beekeeping story with you!

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3rd April
"First beekeeping lesson! Great fun."

Todays Beekeeping suits look GOOD!

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10th May
"The beekeeping stuff arrived today! It's like Christmas! Tried on the bee suit, God it's hot. Now, all I need is some bees, maybe I should get a net."
Showtime!

"A beehive typically consists of two distinct parts. A brood box and a Super. The brood box is usually about a foot tall and contains large frames upon which the bees can build honeycomb and raise more bees. When the frames are almost full the beekeeper puts a grid called a "queen excluder" on top of the brood box -this grid is specially sized so that workers can get through but the queen can't - then puts on a Super filled with frames.

Schematic of a beehive 

Mike's brand new hive, smoke gun and tools

The Super is usually half the height of the brood box. The bees then fill the Super frames with honey but because the queen can't get up there there's ONLY honey - makes it easy to extract.

So that's the basics, if you get lots of bees you can add more Supers - more Supers = more honey. If a beehive gets too crowded the workers will create a queen cell , grow a queen, she (or sometimes the old queen) will then leave the nest with about half the bees - which is why you sometimes get swarms."
Incidentally, the hive, like most in the world is based on the Langstroth design from the 19th century. This was the first design that allowed individual combs t obe removed and took advantage of the observation by Huber that bees would keep a "bee space" of 5-8mm between combs. As this is the space between the combs in a Langstroth hive, the bees to not join the combs up. This enables the beekeeper to slide any frame out of the hive for inspection, without harming the bees or the comb, protecting the eggs, larvae and pupae contained within the cells. It also meant that combs containing honey could be gently removed and the honey extracted without destroying the comb. The emptied honey combs could then be returned to the bees intact for refilling. Langstroth's book, The Hive and Honey-bee, published in 1853, described his rediscovery of the bee space and the development of his patent movable comb hive.

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22nd May
"Interesting beekeeping tidbit I picked up from today's lesson.....bees can sting through your protective rubber gloves. Little sod. Still, I took it like a man, no crying or screaming, just a "ow you little git - you die now!" (which of course he was going to anyway, still........)"

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12th June
"I was given a hive chock full of bees by a chap who had to give it up because he became dangerously allergic to bee stings (this can happen). As a result the beehive I got had not been inspected for 8 months - you're supposed to check them weekly when it's warm and dry enough.

Got to the allotment, the hive is very heavy but can't check it for about a week to let the bees settle.

There is a big IF about them settling down, common bee rules state that you move a hive either 3 feet or a minimum of 3 miles otherwise the bees will go back to the original spot. Well we've moved them just under 3 miles so they might not stay - we're keeping our fingers crossed."

The 2nd Hand Hive, complete with bees...

So how do bees make honey? Well, what happens is that the worker bees extract nectar from flowers and store this in their extra stomach (called a "crop") where it is chemically modifed by enzymes. When back in the hive, the honey is passed between bees several times by regurgitation until it is eventually placed in in a honeycomb. But it is still a thin liquid, so bees flap they wings to evaporate much of the water off before sealing the honeycomb cell with wax.

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18th June
"The girls seem to have settled in! Gonna open up the hive tomorrow and see what sort of population I have. The hive could be full of honey or full of disease or parasites, I'll find out tomorrow, fingers crossed."

Video here

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19th June
"Well I did it. Took the top off and unfortunately the top super (layer) didn't have any frames so the bees have made their own combs. Also, there's eggs and larvae in the upper layers so no idea what's going on there. Gonna have to bring in an expert. No sign of disease though."
.....A lot of bees

Bees had got busy in the top section of the hive,
 making their own honeycombs

Video here

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24th June
"So today, with the help of an experienced keeper I took a look at what I had. The hive consisted of TWO Supers and a brood box. The queen excluder was on top of the brood box. So far so good. We saw that the top Super had no frames and so the bees had build their own combs which were all over the place. We decided to look at that last because it was heavy (hopefully with honey).

We looked at the middle level Super. LOTS of bees, AND grubs and sealed brood cells and honey - obviously the queen had got above the queen excluder, there shouldn't have been young bees in there. No sign of the queen though - you check every time for the health of the hive and to make sure that the queen is OK, she's hard to find in 50,000-odd bees because she's only a bit bigger, so as long as you can find eggs in cells you know the queen is in there somewhere and still working hard. Well we found no eggs, so we took off the queen excluder and checked the brood box. Every frame had either empty cells or cells with nectar, pollen or honey. No queen, this is bad, very bad- she may have left but in that case why were there still so many bees in the hive?

Beekeepers! This is not the Queen you are looking for...

We decided that maybe we'd missed something and we'd check again the following week. So, to the top Super with the natural combs. We took the cover off and it was brimming with bees, there was brood in the cells too. With natural comb we couldn't look for the queen but we did find a capped queen cell (with a pupating queen) AND an uncapped one with a queen larva inside. Maybe the queen is in this level then.

...Neither is this...

So, no honey for me and a real conundrum. The beekeeper and I discussed various options. Eventually we came up with a real risky plan. I have a spare empty hive so, we carefully (VERY carefully) cut the capped queen cell from the natural comb, we then placed it in the older hive carefully UNDER the queen excluder. The plan is that this queen cell will be tended by the existing bees and she'll take over (she'll have to leave the hive to mate and hopefully come back). We then put a new Super on top with new frames in it.

....close, but still no cigar..

The other crammed Super was placed on top of the new hive brood box with no queen excluder (they call it a brood and half), hopefully the bees will use the extra space in the brood box to keep going. If the old queen is in there and a new queen hatches they might not swarm because there's lots of space for them now so they'll probably fight to the death, cruel but that's survival of the fittest for you.

...Bingo !

Eventually I'll have to get the bees out of the natural honeycomb, destroy it and put in proper frames but that's a long way off.

So, no honey for me yet BUT, if my plan works I might end up with TWO hives - of course I could end up with two dead hives if it doesn't work. Fingers crossed."

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7th July 2016
Thought it might be nice to fill in a little information about the group that provided beekeeping training to Mike - the Chesterfield and District Bee Keeping Association.

The CDBKA website is very good, and contains a lot of interesting information. For example, did you know that worker bees only live for 4-6 weeks - except for the last brood of the year that live all through the winter maintaining the hive (and keeping it warm by flexing their thoracial wing muscles to create heat)? No? Neither did NSB until reading one of the articles on the CDBKA website.

Lots of fascinating info on the "General Beekeeping" page also, including an article on how Australian researchers have been placing tracking backpacks on bees to study their behaviour!

Bee with a backpack, obviously!

An article on the CDBKA can be found on the "Bee-Craft" website, which bills itself as the "The Informed Voice of British Beekeeping". The article describes how the group worked hard to replace the post-war beekeepers who were retiring at the end of the 20th Century, and managed to increase members by 19% year on year. This growth in interest was then accelerated by media articles sounding alarm at bee population levels - in one 18 month period members increased from 85 to 160!

And the CDBKA has some high profile alumni, for example, Kim Schofield, beekeeper at the Longshaw Estate.

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24th July
Update from Mike: "OK so bee update...last Tuesday a friendly beekeeper came and delivered a queen with a load of bees. We put them into the bigger hive with a layer of newspaper separating them. Well today I went down to check...either I'd find a settled queen or a load of dead bees. I didn't find a queen but I did find larvae. Couldn't see any eggs but larvae could be a good sign (of course a worker may have started laying drones) FINGERS CROSSED that's not the case. There's a hell of a lot of honey in there - I'll have to add another layer sharpish.

The smaller hive has eggs!!!!! The bees in the smaller hive are more placid too, didn't need smoke to check them. They're building new cells on my new frames instead of just in the natural comb.

This is the situation in the (smaller) Hive 2

I'm still praying but things could be looking up."

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7 Aug
Update from Mike: "A new bee being born! Just one of about 50,000 but pleasing to see nonetheless. And I didn't get stun!". Video here.

Bee emerging from cell (arrowed)!!!

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22Aug
Update from Mike : "So a pile of wood and nails.........
You won't find this in IKEA...

an hour later has become 10 honey frames....huzzah"
Voila! More frames!

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23Aug
Update from Mike :"10 frames ready for extraction."
Honey Laden Frames removed from the Hive 

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26Aug
Update from Mike: "I was expecting maybe 10 jars, got 24 in total!!!!!! PLUS the combs are intact so they go back into the hive,the bees will clean and repair the combs (and lap up any remaining honey). No more honey until next year though, time to start prepping for winter.Honey in my coffee,on my toast,on a spoon. Time to make some mead too methinks." And that honey was from just one super which was about 80% full. I left another super which was half full at that time and the brood frames were about 30%full of stores but the queen was still laying eggs like crazy. I'd taken the frames to Ropers Honey in Sutton Scarsdale - about 5 miles from home, how lucky is that? They spun the honey outwith a centrifuge and bottled it for me. They could have melted it and given me the honey AND the wax but if possible it's better to keep the frames intact.
Honey from honey laden frames now in jars!

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29Aug
Update from Mike: "Checked on the bees for the first time since taking the honey. The big hive was ok actually, the bees were pretty calm but hadn't started working in the new frames yet so I took them out and replaced them with the frames which had the honey taken. These frames were pretty much intact because the honey was spun out so by putting in these frames the bees just have to do some repair work to the comb and they're good. There's also lots of residual honey left over so they can recover that too.

Getting them ready for winter now so time to start parasite treatments - it's a bit fiddly but it started ok, next dose in two weeks. All good.

Then hive number two, the little one. Still no progress on any new frames AND they're doing all their work in the natural comb which is no use to me. Also, my God they are aggressive! Almost the whole hive rose up and started banging into me, eventually two of them stung me through my gloves, I hadn't been trapping them between my fingers (which is why I've got stung up to now), they just landed on my hand and bang! Finished the check anyway and got the heck out of there.

I had noticed a lot of wasps hanging around and this is the time of year that you can get a lot of 'robbing' of honey stores by wasps. So I made so wasp traps and came back later and installed them around the hives. The bees shouldn't get caught because they don't want jam. Anyway I'm sat beside the hives, closest to number one and watching them both -they were VERY busy which is great- when I saw a black shape getting closer to my left eye, of course it was an angry bee (from hive two I'll bet) who then bashed into my eye. I start flailing at my face, catch the sod but not before she stings me about 5mm under my eye (yes I did yell out). Pack everything up and lock up the allotment, get to the car and look in the mirror - the sting was still in there, took a while to get it out too - full dose. It's not very swollen but it IS very painful to touch. Hope it doesn't swell up tonight which is a possibility.

Still love my bees, apart from hive two, those girls are all jerks.

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10th Oct 2016
Update from Mike : "So once I'd got the honey home I then went back to the hive and re-installed the frames, they still had a small amount of honey in them so the bees could extract that and store it. They started on it immediately. Within one week they had removed all of the honey dregs and repaired a lot of the comb (some of it got a bit squashed in transit) so I then removed the super with the empty frames and put them In a sealed bag (to protect them from wax moths) leaving just one super and one brood box on the hive.

I started the Varroa treatment, a pan of white goo sits on top of the frames for two weeks. The bees paddle in it and spread it around the hive. This stuff kills the dreaded Varroa Destructor mite. These days every hive has them and the only hope is to keep the numbers under control. I can check how well it's working by removing the bottom tray from the hive, on hive 1 I usually see two or three [dead mites] on there per week, after the mite treatment there's over 60! The nasty hive (hive 2) has over 100 [dead mites]. So it's working.

After two weeks, remove the goo and put in a new one, this is to catch the sneaky little devils that hid in a sealed brood cell. So after another two weeks I remove the goo for the last time this year - around new year's time I'll try another treatment but the dead mites in the tray are numerous which is a very good thing. The queen has slowed right down with her laying and the brood cells are more filled with stores than brood.

[NB: This paper suggests that "Overall, results suggest that varroa mites could be the main culprit for the death and reduced populations of overwintered honey bee colonies in northern climates."]

Varroa Destructor mites on bee pupae

Then I made a big decision, I decided to go 'brood and a half'. This means that I moved the queen excluder from the brood box and put it on top of the one [half sized]super. So now the queen will have access to the brood box and the -half sized- super. More cells should equal more eggs larvae and BEES and so hopefully more honey - as long as the queen is young enough and strong enough.

So then I have to start 'feeding' the bees, just to make sure that their stores are chockablock for winter. I put a top feeder in the hive crown board over the entrance hole. It's a small plastic tub with a 50mm circle cut out of the lid into which a tight stainless steel mesh is stuck. Fill it with sugar syrup (2lbs sugar dissolved into 1 pint if water), put the lid on, flip it upside down and a lit bit drips out but the rest stays put. The bees can then drink from the mesh. So they're chugging it like mad -almost a litre a week but the mild October weather is keeping them active. I've closed the hive entrance down to only a 60-70mm opening to reduce the risk of wasps and other bees (especially those from hive 2) getting in and stealing honey -something that can happen a lot, especially if another hive is low on stores."

Feeder - bottom of tub has small hole covered in wire mesh.
Dark brown is just top of hive, not a layer of  feed!

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30th Nov 2016
Update from Mike: "Checking the hive on Sunday. All quiet but still some bees occasionally coming and going. Some dead bees on the ground around hive 1 (friendly hive) but lots of dead bees around hive 2 (not so friendly hive) - around twenty of them. Also two bees dead at the entrance, just sitting there like they decided 'sod it, it's too cold' and died on the spot. Took the lid off hive 2, felt the top and it was cold, put my ear to the top and gave the hive side a tap and could still hear them buzzing so they're still OK.

Put the lid back on hive 2 but noticed that I'm giving shelter to other mini beasts too.

Hive 1 looks OK, very quiet but as I said still some bees coming and going, the weight of the hive indicates good honey stores for the depths of winter."

Ladybirds

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12th Dec 2016
Update from Mike : "Checked the bees on Sunday. Still noise from both hives but looking at the ground at the front of the hives you can see a big difference. These may just be early autumn bees that have finally run out of energy, the winter bees being much more long-lived. Or it could be an indication of hive health. Either way the surviving bees will always throw out a dead or dying bee to keep the hive free of disease and mould."

Dead bees circled in red on the ground outside Hive 1

Dead bees circled in red on the ground outside Hive 2

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22nd Dec 2016

Update from Mike : "Last Saturday I went down to the hives and applied a different form of Varroa mite treatment. In this case using oxalic acid. This is strong stuff, a lot more aggressive than citric acid for example and is bought in powdered form.

Oxalic Acid

What we do is we heat the powder so that it sublimates - goes from solid to vapour. You can buy expensive heaters for this task but I just bought one of those car plug-in water boilers - the kind you plug into the cigarette lighter and immerse it in a mug to heat water. Make a little cup of foil and sit it in the middle of the heater element, add the powder then connect it to a 12V battery - voila, sublimation. We do it at this time of year because there should be no developing brood (eggs or young larval bees) in the hive, the fumes won't harm capped brood but open brood cells will be killed by the vapours.

The fumes are nasty and certainly not good to breathe, the bees don't like it at all but as long as you get the dosage right it does them no lasting harm, but the smaller varroa mites hate it and should drop off any bees and die.

[Interestingly, oxalic acid is also used by the Fenestraria plant to produce optical fibres that direct light into the photosynthetic parts of the plant. Researchers are wondering if this might have applications for solar panel technology.]

Fenestraria - note transparent tips

So I did both hives, applying the vapour through the bottom of the hive, instantly the quiet hive began buzzing and because I'd blocked the entrance they had nowhere to go. It was trickier with hive number 2 because they've sealed the top vents with honeycomb so I don't know how well the vapour got into the hive - they certainly seemed upset about it so maybe that's a good sign.

I'll check under the hives this weekend to see if there's a lot of dead mites under them - fingers crossed.

Because I wanted to support hive number 1 -and say sorry for gassing them- after the treatment I placed a block of fondant on top of the top vent hole on the hive. It's in a take-away plastic container which has access holes melted into it. Sort of an early christmas present too. Within 5 minutes of placing it on the hive it was covered with greedy bees all stuffing themselves. This was a good sign after the treatment AND it will help to make their honey stores last even longer which judging by the weight of the hive are substantial."

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23rd Jan 2017

Update from Mike : "Deep in the heart of winter the bees need to be left alone now. I just check on them once a week to make sure that there's no outward cause for concern such as damage from weather, animals or vandals (which does happen to some hives apparently). Another thing we do is 'heft' the hives, we gently lift the hives up with one hand on one side of the hive to get an idea of how much they weigh. A heavy hive still has lots of stores and is doing OK -remember that the bees still need food and at this time of year honey is what they have (remember I also put some fondant in Hive 1 too to supplement their honey stocks).

Hive 1 (the friendly one) is really heavy and so I feel re-assured that they're OK - I'd like to see inside but don't want to disturb them when it's this cold. Hive 2 is VERY light, this hive is full of very aggressive un-productive bees so I'm not helping them at all. My expectation is that they'll die out before spring which is a shame but aggressive bees are not nice to have and if they're not productive (or bred to recognise the need to build winter stores) then natural selection will take care of them.

My Christmas present finally arrived, I've got time to give it a few coats of Cuprinol then let it sit out to get a bit weathered then I'll fit the inner brood box and supers - then if a swarm becomes available I'll be ready. The old wooden hive from Hive 2 will be binned, it's a National/Hybrid model which I don't like. Anyone want a hive?"

New Hive !

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10 Apr 2017

Update from Mike : "Checked on the bees properly for the first time this year.At the moment the friendly hive is composed of one brood box topped with a half brood box and then there's the queen excluder with a super full of frames on that. The bees have already half filled the top super with honeycomb and nectar so progress is good. Lots of brood and stores in the brood sections but there's a LOT of drone brood in there which is unusual this early in the year - might be a sign that they're thinking of swarming, maybe not, the queen is laying eggs at a good rate and there's plenty of space so I'm doing what I can to reduce the swarm impulse.

Schematic of a beehive 

Unfortunately the top half brood box has odd sized frames and this has allowed the bees to build comb between layers so when I pull out the half brood frames for inspection I destroy the extra comb - which has brood in! Not nice to see larvae and pupae spilling out. So I had to take drastic action - with the help of another beekeeper I removed the half brood layer and replaced it with another super filled with empty frames, then I put on the queen excluder and then the half brood level with the dodgy frames, on top of that went the half-full super.

So now the brood will hatch from the half brood but with the queen excluder in place the bees will refill the cells with honey. The super underneath the queen excluder with new frames will take a while to be re-populated but once the bees have drawn out the comb they can start using it for brood again. We scrutinised the half brood frames very carefully to try to ensure that we don't trap the queen above the queen excluder - that would be a disaster and I won't know for sure if she WAS in the bottom level until I do another inspection next weekend - if I find eggs or young larvae ABOVE the queen excluder then I know she got above it and I have to find her at all costs.

Whilst doing the check I saw that one of the larvae which had fallen out had THREE varroa mites on it. They were the only ones I saw but I'll have to put the varroa floor at the bottom of the hive this weekend and then a week later count how many of them have fallen onto it. There's a nifty calculator on the National bee Unit website that gives you an idea of what sort of infestation you have based upon the fall of varroa - it also tells you when and what action to take. If it's bad I could lose my honey harvest so I'm keeping my fingers crossed.

Larvae with varroa mites

Whilst checking I found a huge dead bumblebee at the bottom of the hive. It had been stung to death obviously but it had also been plucked - apparently this is a common practise for bees when they encounter a dead bumblebee - opinions vary as to why they do it.

Dead Bumblebee "plucked" by honeybees 

The nasty hive is still going, albeit with a reduced population. I never fed them at all during winter and yet they hung in there - still naggy little devils though.

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Related links
Nottinghamshire Beekeepers Association
Derbyshire Beekeepers
Article on how African Farmers use beehives as elephant repellant
The National Bee Unit

Related NSB Content
Talk on reproduction in Bedbugs
Talk "From Soil to Supper"
Wildlife in the Garden
Talk on Dungbeetles and Drugs

Image Sources
All by kind permission of Mike, excepting the following:
Bee with Backpack; Queen, Queen, Queen, Queen
Varroa Destructor Mite, Fenetraria, Oxalic Acid