In my earlier post on the Learning from the Bees conference, I discussed the “who was there and what it was about” aspects. This article covers what I actually learned about bees.
I always particularly enjoy lectures and books covering “weird stuff I have seen over many years which you won’t find in any book” and there were several speakers on this, and opportunities to learn about exotic situations from foreign beekeepers.
There is debate about whether bees prefer clean floors, or ones covered in leaf litter etc to encourage an ecosystem of fungi and creatures such as book scorpions which kill & eat varroa mites (mutualism). Some people also reckon eco-floors act as a buffer to regulate humidity in the hive.
What bothers me about them is that the arguments in their favour seem somewhat arbitrary, and the only hard evidence I’ve heard put forward in their favour is that when you open a feral nest, the hive floor is covered in detritus. Indeed that is what I saw the one time I helped with a cut-out, but this is not the whole truth. I have heard just as many people say that they cut out a feral nest and the floor was propolised and clean. (Also, it’s been noted that hygienic bees in hives tend to keep their floors very clean.)
The only way to tell what bees prefer (clean versus messy floor) is to ask someone who has done many cut-outs. A while ago Jacqueline Freeman told me she had done about 12 cut-outs, and what she observed was:
- If the comb comes down to within a few inches of the floor, the bees clean the floor and propolise it. The floor is extremely clean.
- If the comb is a long way from the floor, say a foot or more, the bees ignore it and detritus builds up.
At the conference I asked Professor Tom Seeley about this. He has opened many feral colonies. He agreed absolutely with Jacqueline. I think that’s pretty conclusive – bees prefer clean floors in hives. However… as usual, it turns out things are a bit more complicated than you first think, so read on…
The latest research on book scorpions
Tiny stingless “book scorpion” arachnids, native to the UK and Europe, are being trialled in hives by some beekeepers to control varroa. A bit of back story is worth mentioning here. John Haverson told me that a really old beekeeper told him that whip scorpions used to be endemic in British hives …until the introduction of the miticide Apistan! Here is a compelling website on the use of these creatures to control varroa, and a fascinating blog post about the lead researcher in this subject, Torben Schiffer – who was at the conference. There is so much to say about this man’s work that it is probably worthy of a blog post, once I’ve digested his book.
My interim conclusion on eco-floors and book scorpions:
On balance, I think book scorpions have been shown to work well for pest control in some hives. Germany’s climate isn’t too different to mine so they may work here too. I know a few people who have trialled eco-floors and see no adverse effects on the bees.
However, I am wary of eco-floors (which book scorpions need) as Small Hive Beetle will find floor litter an ideal place to lurk when this pest arrives in the UK – I understand SHB have very tough skins which bees can’t bite through so I think book scorpions are unlikely to predate them. Also I find clean, bare floors useful as inspection trays which I can pull out to examine the floor litter. So personally, I am going to continue with the bare floor policy, whilst watching this research with interest and trying to keep an open mind.
Edit: supporting evidence – it appears bees dislike eco-floors near their comb: Malcolm Robinson in Tasmania observes (in a post to the Warré beekeeping mailing list, 20.12.2018):
Our ecofloor had been ‘normal’ for months while our colony got established and over-wintered.
In the spring, we added two new boxes as the existing space was filled with comb but we were a bit slow adding a third so the bottom box had been full of comb for a couple of weeks.
When we went to add that box, we found that the ecofloor had been totally propolised.
It’s going to be interesting to see what happens under the propolised layer!
Positive and negative selection
Speaker Tjeerd Blacquiere wrote the influential paper A Plea For The Use Of Honeybees’ Natural Resilience in Beekeeping. with Delphine Panziera. They are part of the COLOSS research on natural selection for varroa resistance, and stressed that you can’t eliminate the mite completely so a chemical approach is of limited use. Miticides, of course, select for resistant mites and dependent bees, and hinder natural selection for resistant bees. So far, I was familiar with these ideas. Then he introduced a couple of concepts new to me:
- Natural selection is passive – “negative selection” – undesirable stock dies.
- Targeted or “positive selection” as practised by breeders, discards mainly fit colonies, greatly reducing the genetic range of the stock. Breeders may only keep 5% of their “best” colonies.
Tjierd’s group have been using negative selection in apiaries over the last 10 years, and typically get varroa resistance developing in 4 years.
(There was some debate over the methodology as they use splits of the best colonies to accelerate the process, rather than waiting a few extra years for true natural selection but this was the overall thrust.)
Tom Seeley’s talks
These were primarily about natural selection. He stressed that after 30M years bees are very well adapted, for example they are much more efficient users of wax than bumblebees. Originally tropical insects, honeybees have adapted to cold weather by clustering rather than hibernation. He finds the colony level traits the most remarkable.
He told us of the Loper study monitoring natural evolution of varroa resistance in feral colonies in Arizona’s mountains. The take-home points here are:
- The varroa resistance simply from natural selection climbed to nearly 95% in a few years, and this was about the same time as it took for a human-directed breeding project, “the famous Minnesota gene line” to deliberately breed for 100% resistance. So is there any advantage to using managed breeding techniques?
- Looking at wild resistant bees in his own stamping ground, the Arnot forest, Seeley found they didn’t have one particular trait that conferred resistance. Instead they had evolved a range of anti-varroa tools, which tipped the balance in the bees’ favour, and the entire suite was as effective as one super-selected trait.
- “Natural selection doesn’t care about how. And it continually fine-tunes the bees. Natural selection has no single ‘magic bullet’ solution; instead the bees develop a range of tools.”
- Mitochondrial DNA analysis showed the Arnot Forest queen lines had reduced from 11 to 3 lines after varroa arrived, and nuclear DNA aalysis showed big shifts in 634 locations. This indicates a genetic bottleneck killing all but 10% of the stock. However, bees which are selected by breeders have significantly less variation, i.e. are more inbred, increasing the dangers of colony weakness and collapse, and reducing their resilience to new problems.
Foraging: He mentioned honeybees have been found foraging up to 8.4 miles from their hive! Pollen foragers put pollen into cells themselves, but it’s more efficient for nectar foragers to pass the nectar on to a house bee and take off again immediately, because nectar needs processing.
Life span of a worker: Another fun fact: workers in queenless colonies can last for months because they’re not working as hard! This is why queenless colonies can take a long time to dwindle away.
Other key findings of Seeley’s are that wild colonies prefer to be spaced almost 1km apart, and he confirmed experimentally that pests spread much more effectively in crowded apiaries; they prefer smaller cavities than they get in Langstroth hives (note, smaller cavities promote swarming); and they like to propolise their walls. Controlled experiments showed all these factors strongly influence survival. These may seem obvious, but Seeley was the scientist who tested and proved these hypotheses.
Albert Muller’s Meditations on the Hive talk
AM started beekeeping in 1975 and shared some observations of his.
Queen fights: These may not actually be fights. He described seeing an afterswarm with 5 young queens. After a few minutes one walked out of a big clump of workers, who seemed to have chosen her, and stung the other queens who did not resist. This chimes with an observation by Gareth John of a queen fight in a 2-queen swarm where one queen appeared to freeze and submit to the other’s sting, as if they had all decided this was best for the colony.
AM also mentioned that drone cell wax is different to worker cell wax. It melts differently (more solid than worker cell wax) and candles made from it are “calm, whereas worker cell wax candles have a nervous flame”. He reflected that he’s never seen a nervous drone: they are always calm.
Afterswarms are all daughters (their mum went off with the prime swarm). This strikes me as significant, I need to think further on this. Another point worth keeping in mind about afterswarms is, they tend to carry less food with them.
Workers are programmed to return to exactly where their hive entrance is: if you move a hive 50cm forward, returning workers bounce off the front of the hive! Drones, however, are not confused: if you move the hive after the drones have flown off for the afternoon drone mass congregation / mating flight, or close the main entrance and open another above it, the returning mass of drones returns straight to the entrance. Obviously this ability is useful for the sex which hops between hives.
The conservation status of honeybees
This conference was the first time I’d heard that some conservationists have taken exception to honeybees being in conservation areas. There are several reasons, all based, I think, on muddy thinking and false reports:
- There is some evidence that honeybees are stealing nectar and pollen from other species, such as bumblebees. Personally I think this is overstated as honeybees exhibit flower constancy, and ignore scarce, scattered flowers such as those found in wildflower gardens, looking for large areas of one blossom (like a tree, bush or crop) which they can direct their co-workers towards. In my experience, bees tend to only go for individual flowers if there are vast numbers of the flower in a relatively concentrated mass, as sometimes happens with e.g. dandelion weeds on unmaintained fields.
- Honeybees are sometimes arbitrarily described as an agricultural species rather than wild animals. Opinions vary! This is actually a really significant legal point. A few years ago the EU proposed reclassifying them as domestic animals, which would have meant all kinds of government monitoring of beehives. That suggestion was opposed by various countries’ beekeeping bodies.
- Honeybees are sometimes claimed to be “non native”. Whilst this is true in the Americas, they have been in Asia and Africa for millions of years, and have been in Europe since at least the retreat of the last Ice Age’s glaciers. To argue that was “only 11,600 years ago” is to ignore the fact that no insects are “native” to northern Europe by this measure.
Miscellaneous tips from British and foreign beekeepers
American beekeepers mentioned problems we don’t have, like bears, skunks, and one even found a black widow spider in a hive. Skunks eat bees as they appear at the hive entrance, and will eat wasp nests too. I think they were surprised to learn we do not have bears in the UK. (The last one here was killed around 1000AD.) Apparently bears are only a problem if they learn hives = food, like our badgers which will coexist with hives for years until the ground is too frozen for them to get worms and they look for other food sources.
Kay & Sue from the US told us they use wasp pheromone in their wasp traps. We Europeans hearing this thought it somewhat unsporting!
Kay & Sue are pretty sure their bees get high on poppies.
Another Kay, from Scotland told us she has 3 hives under a massive wind turbine and they seem fine, despite some peoples’ concerns about vibration and electromagnetic fields from these disturbing the bees. She’s planning a hive made from a whiskey barrel.
Some South African conservationists told me about the propolis shells round their local nests. The bees continually work these so they remain tacky, which makes them fire resistant. They were amazed European bees allow their propolis to dry hard, and thus become flammable.
Australia has no varroa but does have Small Hive Beetle, the reverse of the UK position. Warren and Jon reckoned SHB will only be a minor problem in the UK because of its cool climate. Where they live (Canberra) SHB is only occasionally seen, but 100km north it is a problem, and 100km further north – the tropical part of Australia – is infested with SHB. In their experience, strong colonies do not have problems with SHB but they warned do not open hives, this triggers the SHB to start breeding! If you do have SHB, use traps which can be slid in and out of the base of a hive without opening it. (This chimes with something else I have heard about conventional beekeeping practises being completely inappropriate for these pests: regularly opening a hive sends a plume of hive smells downwind, and SHB will be attracted from 10km away, also the shorter-range Asian Hornets.)
Are out apiaries worth it? It’s common practice to split hives into small groups across a region. But Paul High from Northampton told me he concluded out-apiaries are only worthwhile if your home area is poor in forage: he was spending a lot of time and money driving to and from them; he never caught the swarms from these hives; and for some reason they gave less honey than the ones he kept at home. So he brought his out-hives back home and gets more honey, plus the swarms.
John works with prisoners and hives at Rugby prison. He dislikes bee stings for an unusual reason – each one means an hour’s paperwork.
Thoughtful comments by various participants
- “The most important thing I’ve learned about bees is their gentleness, such as when a swarm was knocked onto my head and I got no stings.”
- “As a natural beekeeper surrounded by conventional ones (in Wales) I always felt a bit embarrassed, but not now: I am very moved by this conference.”
- “The bees know what to do: all we need to do is give them a safe dry box.”
- “After a few years treating bees with chemicals, it struck me I would not like my house fumigated, so I went treatment-free.”
- “Invasive inspections teach me nothing I don’t already know from external observation.”
- “Just because they’re not gathering honey don’t assume they’re not doing anything important. Whenever I inspect my bees during a pause in foraging, they’re raising brood, housekeeping, grooming mites off, etc.”
- “We’ve normalised growing food in poison.”
- “Colonies are well adapted and buffered, so if one dies it means a BIG problem (or many small ones).”
- “Killing drone brood is like colony castration.”
- “Suppressing swarming can kill colonies (one reason: there is no brood break to limit varroa).”
- “Propolis is so important to bees that you can see them mining it off used frames, after they strip out honey and pollen.”
- Some people start beekeeping fully suited, then as their mind-set changes they find this isn’t needed. They say you don’t have a transactional, or conditional, exchange with bees. The bees give, unconditionally. I loved the terms other beekeepers gave these experts – spiritual, shamanic, voodoo beeks – or in one case “we call him the Bee Whisperer, because he walked up to a hive everyone else was scared of, without a veil or anything, and they calmed right down“.
- “I feel I can tell when a colony begins raising drones – the tone of the hive changes – almost like a party atmosphere!”
- (From a South African bee conservationist): “You Europeans are crazy, let the bees live in trees!”