“Honey bees do not mind being quite high up”: but is rooftop bee-keeping a good idea?

Bee hives atop Fortnum & Masons. Image: Getty.

What links the London Stock Exchange, posh grocer Fortnum & Mason and the Scottish parliament building in Edinburgh? All great institutions, of course, but they have also proudly introduced beehives to their rooftops. The Conversation

In the midst of worrying stories about declining bee populations, it has become a popular pursuit. Businesses and government install the hives with great fanfare to signal their green credentials. But is this actually a good thing for honey bees, beekeepers and the public?

For beekeepers it is clearly more convenient to keep hives at ground level. The bees do fine, and level locations are plentiful in most areas. Both ground and roof locations require beekeepers to carry out routine and seasonal management, such as hive inspections and honey harvesting. However, hive equipment is bulky and heavy. Steve Benbow, a commercial beekeeper in London, has described the effort of carrying hives to the roof of the Tate Modern art gallery via chambers, lifts, corridors, and a final ascent up four flights of stairs. Moving stuff is a lot easier at ground level.

High honey. Image: author provided.

Swarm behaviour

Then there are the swarms. Each spring, beekeepers have to manage this natural part of the life cycle in which a colony divides – swarming is how honey bee colonies reproduce. The swarm, when it leaves the colony, can contain 10,000 bees. Beekeepers manage their hives to prevent swarming. However, prevention is never 100 per cent. If swarming does occur, the swarm usually settles near the parent hive and can then be put into an empty hive and moved to a more convenient location.

Swarming from a rooftop probably makes little difference from a bees’ perspective. But the swarm is liable to be more of a public nuisance. Mark Patterson of the London Beekeepers Association told us that swarms from high-rise hives often settle high. He recounted episodes of abseiling down buildings, calling in the fire brigade and using window-washing platforms to collect central London swarms originating from high-rise hives.

Swarm! Image: Grande Illusion/Flickr/creative commons.

So much for our convenience, what about the bees? Well it is true that honey bees actually prefer to nest above ground level. Tom Seeley, a honey bee biologist at Cornell University, has shown that swarms are picky when selecting a nest site. By attaching plywood bait hives to trees he found that swarms prefer five metres above ground to one metre.

When Seeley located wild honey bee colonies in hollow trees in a nearby forest he found the average height was 9.7 metres (in a range of between 5.3 and 17.3 metres). That’s about three storeys high.

This shows that honey bees do not mind being quite high up, at least when nesting in a forest. We don’t actually know why honey bees in the wild prefer not to nest at ground level. It may provide protection against predators such as bears. Urban hives at ground level are unlikely to be predated, other than by humans, of course.


Altitude attitudes

In the UK, hives on iconic buildings such as St Paul’s Cathedral in London, can be very high up, 52 metres in that case. This is higher than bee colonies live in trees. Is this good for the bees? As far as the risks to a successful colony go, James Fischer, a New York rooftop beekeeper, told us that hives above 10 storeys are “speculative ventures”; those above 15 stories are on “life support”.

Research has yet to establish if height itself is an issue for honey bee colonies. Honey bees routinely forage several kilometres from their hive. To a bee, flying level or flying vertically should make little difference as air resistance, not gravity, is the main challenge. Flying vertically to a hive at 50 metres would be negligible extra distance.

More obvious is the fact that apiary sites should not be too exposed. Beekeepers know that good locations should be sheltered from the wind and this may be harder to achieve on roofs. Tall buildings often cause the wind to form unusual draughts and eddies.

Sweet reward

What is the real motivation for keeping rooftop hives? With trendy London honey retailing at up to four times the price of a similar Leicestershire honey, financial reward is one incentive. A somewhat different motivation is the desire of businesses and government bodies to showcase environmental credentials, by helping to save the “endangered” honey bee.

Image: National Bee Unit, Author provided.

However, this may not actually be helpful, particularly when it adds more hives into an area where there are already many, as seems to be the case in London. More hives increase the risk of spreading bee diseases and annoying neighbours. Overstocking can also increase competition for nectar and pollen which is not good for honey bees or beekeepers, or other pollinator species. Many towns, and especially central London, probably already have as many hives as the available flowers can support. Most people will have no clue that each new hive will consume the floral resources produced by the equivalent of eight hectares of lavender.

Keeping bees can be a fascinating hobby. And with the surge of interest in urban farming, sustainability, food security, and the environment – as well as intense media focus on bees – it is not surprising that beekeeping is becoming increasingly popular. People who take up beekeeping or staff who join corporate beekeeping projects often report genuine benefits such as more contact time with nature.

But beekeeping isn’t easy. For a novice, the reality can easily be dead colonies and no honey, rather than the hoped for abundant harvest. Once people start to question the motivation for installing yet another rooftop hive, they may find that more benefit could be gained, for bees, humans and other flower visiting insects, by growing flowers that provide nectar and pollen for all pollinators.

Karin Alton is a research fellow in, and Francis L. W. Ratnieks professor of, apiculture at the University of Sussex.

This article was originally published on The Conversation. Read the original article.

 
 
 
 

Which pairs of capital cities are the closest together?

Vienna, which is quite close to Bratislava, but not quite close enough. Image: Thomas Ledl

It doesn't take long to get from Paris to Brussels. An hour and a half on a comfortable Thalys train will get you there. 

Which raises an intriguing question, if you like that sort of thing: wich capital cities of neighbouring countries are the closest together? And which are the furthest away? 

There are some that one might think would be quite close, which are actually much further part. 

Buenos Aires, Argentina's capital, sits on one side of the estuary of the Río de la Plata, while Montevideo, Uruguay's capital lies on the other side. 

Click to expand: Image: Google Maps

But at 207km apart, they're not really that close at all. 

Similarly, Singapore – capital of, er, Singapore – always sticks in the mind as 'that bit on the end of the Malaysian sticky-out bit'. But it's actually pretty far away from Kuala Lumpur, Malaysia's capital. A whole 319km away, in fact:

Click to expand: Image: Google Maps

Thinking of 'countries that cause problems by being close together', you inevitably think of South Korea and North Korea. 

Click to expand: Image: Google Maps

And while Pyongyang in the North and Seoul in the South are pretty close together, 181km just isn't going to cut it. 

Time to do some Seoul-searching to find the real answer here.

(Sorry.)

(Okay, not that sorry.)

Another place where countries being close together tends to cause problems is the Middle East. Damascus, the capital of Syria, really isn't that far from Beirut, in Lebanon. Just 76km:

Click to expand: Image: Google Maps

Seeing as Lebanon is currently host to millions of refugees fleeing the horrors of Syria's never-ending civil war and the atrocities of Daesh, or Isis, this is presumably something that authorities in Beirut have given a certain amount of thought to.

Most of the time, finding nearby capitals is a game of searching out which bits of the world have lots of small countries, and then rooting around. So you'd think Central America would be ripe for close-together capital fun. 

And yet the best option is Guatemala and El Salvador – where the imaginatively named Guatemala City is a whole 179km away from the also imaginatively named San Salvador.  

Click to expand: Image: Google Maps

Another obvious place with lots of small-ish countries is Europe – the site of the pair of capitals that drove me to write this nonsense in the first place. 

Click to expand: Image: Google Maps

And in fairness, Vienna and Bratislava do make a pretty good showing of it. Austria's capital sits on the Danube; drift downstream, and you swiftly get to Slovakia's capital. As the crow flies, it's 56km – though as the man swims, it's a little longer. 

There are more surprising entries – particularly if you're willing to bend the rules a little bit. Bahrain and Qatar aren't really adjacent in the traditional sense, as they have no land border, but let's just go with it. 

Click to expand: Image: Google Maps

Manama, Bahrain's capital, is 140km away from Doha, the centre of the world's thriving local connecting-flight-industry which moonlights as Qatar's capital. 

Sticking with the maritime theme, Port of Spain in Trinidad and Tobago is 152km from St George's, Grenada. 

Click to expand: Image: Google Maps

Good, but not good enough. 

Castries, the capital of the Carribbean country of St Lucia, is 102km north of Kingstown, the capital of St Vincent and the Grenadines. 

Click to expand: Image: Google Maps

Better, but still not good enough. 

Basseterre, the capital of St Kitts and Nevis, inches ahead at 100km away from St John's, the capital of Antigua and Barbuda.

Click to expand: Image: Google Maps

But, enough teasing: it's time to get down to the big beasts.

If you ask Google Maps to tell you the distance between the capital of Congo and the Democratic Republic of the Congo, it comes up with a rather suspect 20km. 

 

Click to expand: Image: Google Maps

A short distance, but considering the only thing separating the two is the River Congo, something's up: Google places the centre of Brazzaville a little north of where it should be, and the centre of Kinshasa many many miles south of where it should be, in some sort of suburb.


So, in true CityMetric style, we turn to train stations. 

Though such transport hubs may not always perfectly mark the centre of a city – just ask London Oxford Airport or London Paddington – in this case it seems about right. 

Kinshasa's main train station is helpfully called 'Gare Centrale', and is almost slap-bang in the middle of the area Google marks as 'Centre Ville'. On the other side of the river, 'Gare de Brazzaville' is in the middle of lots of densely-packed buildings, and is right next to a Basilica, which is always a good sign. 

 

Click to expand: Image: Google Maps

And when marking that distance, you get a more realistic 4.8km. If you want to be really keen, the ferry between them travels 3.99km, and the closest point I could find between actual buildings was 1.74km, though admittedly that's in a more suburban area. 

Pretty close, though. 

But! I can hear the inevitable cries clamouring for an end to this. So, time to give the people what they want. 

Click to expand: Image: Google Maps

If you ask Google Maps to tell you how far away the Holy See, capital of the Vatican, is from Rome, capital of Rome, it says 3.5km. 

Click to expand: Image: Google Maps

If you set the centre of Rome to be the Palatine Hill, the ancient marking point for roads leading out of Rome, that narrows to 2.6km.

 

Click to expand: Image: Google Maps

Fiddle a bit and put the centre of the Vatican as, well, the middle bit of the roughly-circular Vatican, that opens up a smidge to 2.75km.

Click to expand: Image: Google Maps

Mark the centre of point of the Vatican as the approximate location of St Peter's Tomb within St Peter's Basilica, which is after all the main reason the Vatican is a thing and not just a quirky suburb of Rome, and 2.67km is your answer. 

Though obviously in practice Rome and the Vatican are as far away as one single step over the railings at the entrance of St Peter's Square, which fairly blatantly makes them the closest capital cities in the world. 

But that would have been a very boring thing to come out and say at the start. 

Oh, and if you hadn't worked it out already, the longest distance between a capital city and the capital of a country it shares a land border with is 6,395km. 

Click to expand: Image: Google Maps

I know it's tough for you, Vladimir and Kim. Long-distance relationships are a real struggle sometimes.

I can't make a pun work on either Moscow or Pyongyang here, but readers' submissions more than welcome. 

Jack May is a regular contributor to CityMetric and tweets as @JackO_May.

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