Sisters can't do it for themselves

Our nest continues to grow and with it the activty, interest and intrigue. At the time of writing I've only managed to count in detail 2 days' worth of CCTV footage, but it's one heck of a two days!

Over the course of the two days - half of which was rainy/windy we saw:

• 304 foraging trips
• 136 memorisation procedures (equates to first flight of new bees - indicative on the minimum number of workers in the nest)
• Orangey/red and pale yellow pollen being collected
• 5 Queen bees performing memorisation (i.e. 5 new queens)
• 2 Queens bringing back pollen (normally a sign of colony building - another colony already developing?)

Here's a recap of today's additional activity.

First of all, Queens. When there's unusal activity going on in the nest, it's easy to start doubting what you are seeing. What seems to happen is I start off with an instinct that something is happening because of a short observation. Then I spend a day or two thinking I'm going mad. Then, I typically see really good evidence that shows it was happening. The I start to think I am still seeing things!

It's like that with the queens. I thought I saw one, but I assumed she was the colony "mother". Then of course I saw two so knew something else was going on. And finally at the latest count, five. 

I can count them, by the way, by combining a number of techniques. First is sequential exits/entrances. If 3 leave without returning, then I know there are at least 3. Likewise, sometimes I will have counted some that have left, and then see more in the nest at the same time, so this also gives a number. Finally, I can count the memorisations - which is done once (usually) for each new bumblebee that goes on a flight. Using all this data serves to give a guaranteed minimum number with a high degree of confidence. 

Anyway, some pics of the queens. Compare the sizes with the regular workers.

 queen returning to nest (CH1)Queen returning with yellow pollen (CH1)Queen with pollen coming into land (CH1)And then the queen goes into the nest - and you can clearly see all her pollen (shows up white under the infra red)

Queen with pollen (CH2)Another queen emerged, but had imperfect wings and was struggling to make her first flight. It took her about 20 minutes of trying to lift off, but she could not sustain flight very well. unfortunately I lost track of her.. 

Queen - foreground - with imperfect wings is pacing the ledge trying to flySince I've been doing some audio recording of the nest this year I also took the chance to measure the audio frequency of these Queens' buzz. The result was 135Hz +/5Hz.  This ties in perfectly with the samples I took from captured queens. It stands to reason that frequency and size are related (in general at least), as is true for the human throat/chest and any musical instrument. It certainly would be nice to have a clear frequency range for queens that guarantee you know what you are dealing with. (I'm not finding a lot of research on bumblebee frequencies).

Fanning

I caught one busy bee "fanning" today. This is the process of beating the wings to draw cooler air into the nest when it is too hot. To be honest, the temperature wasn't that hot. Outdoors it was 16C, and ambient in the nest was 23C (it's been hotter - thought bear in mind this is not the core). Perhaps this particular bee has a low threshold for fanning.

Actually, this was a theory I postulated last year - that different bumblebees have different trigger thresholds. Firstly, from a natural variation point of view it almost stands to reason. But secondly, in terms of a distributed "control system" for the nest that ensures fanning is not "all or nothing" but happens in a controlled way in response to increasing temperature, it makes sense that some bees are more sensitive and start fanning at a lower temperature. As the nest temperature climbs, more bees will be triggered to join the throng. Providing the fanning process itself doesn't generate undue heat, then such a system would basically be wonderfully self regulating (without the need for central command and control), because as more bumblebees start fanning, not only will the effect be greater, but fewer will be working in the nest and generating core heat. 

 bumblebee fanning near nest entranceshe's moved position - still fanning, wings clearly visible in motionThe she moves right to the entrance and continues. She was here for a good few hours (seemingly unnecessarily). 

Still fanning in the entranceI couldn't capture the sound of her fanning, but at peak temperature it sounded as though others in the nest were also doing so, so I recorded some of that and measured the frequency also. Because the sound is coming from the wings more than the thorax, it is not the usual buzz but the whisper of the wings through the air at a slower speed than normal flight (like a room fan). It's hard to determine if there is a fundamental frequency, but for what it's worth, my meter showed 135Hz sustained for extended periods of time. Interesting in that it is the same fundamental as the queens' buzz, but it is not a buzz and does not have the same characteristics. 

Rescuees

It was pretty much certain we'd get some less well bumbles to care for indoors again this year - there are always imperfections in nature. I'd hoped it wouldn't be too soon, but it was today. Actually, this box has gone longer than last years before discovering some under-formed bees. 

I actually found two - and they insisted on coming out of the nest and trying to fly but were unable to. The first one is worst off, with only 1 wing and 5 legs and I found her about 6 feet from the nest. Lucky for her really, as if I hadn't spotted her then I might never have done and she could be starved or bird-food by now. The second one has both wings, but they are crooked, one is too small, and she can't fly. (I made sure for 30 mins in the open that they couldn't, but it's obvious anyway). 

They are both similar size, and very small, under 1cm. I've not managed an accurate measurement yet, but around 8mm I reckon. Possibly smaller than Holly. I'm actually pleased to have found two as they can offer each other company and interact with each other. Last year one of the most painful things was to see Holly behaving as if she was depressed when she was alone (she had company from other bees some of the time, but she outlived them all). You think I'm kidding?  

Here are our two little darlings, just resting nest to each other. Maybe they are bonding ☺ They are certainly getting on fine:

Our two new under-formed bumbles indoors - as yet unnamedAlthough it is not recommended to revive bumblebees by feeding on honey water, we have no option. Sugar water does not provide mineral content, it is just empty energy and not nutrition, so we have to provide honey, even though there is a risk of bacteria. Last year Holly actually survived 70 days in our care, which is as astonishing life span for a worker bee (typically 15 - 20 days). 

a sense of scale

Tonight they have drunk really well and been mooching around with plenty energy, don't seem to be stressed and are co-operating just fine. They won't grow any bigger - their exo-skeleton has developed to this size and that's how it will stay, so they are amongst the smallest in the colony. Perhaps they hatched too soon, or just didn't get the temperature needed for development (which is critical). At least they are mobile. 

I hope these two have a decent lifespan, but whatever the case, we will give them a good quality of life however long it is - free from predators and starvation. 

2 plump girls causing a stir

Last year there was never a dull moment in the bumblebee nest, always a surprise in store, and this year is already turning out to be no different. 

As I blogged yesterday evening, I was already intrigued by the possible sighting of our queen, having seen a few very large bees, but then seeing a massive (or, as I say on twitter, mahoosive) behind trailing over the pots underneath our camera. The difference was very noticeable in her wide, plump tail and abdomen, which I had just managed to catch a parting shot of. 

Queen's tail - top rightThat all changed this morning as I time and time again I saw a massive bumblebee passing under the camera - here's a comparison shot with other the worker bumbles:

A queen-size bumblebee (bottom left) dwarfs the workersMy heart was racing trying to capture pictures of her, because what I really wanted to find out was if she was laying eggs in this part of the nest. And, if she was, the prospect of capturing a bumblebee first emerging from a wax pot upon hatching. It would be amazing footage to capture.

I couldn't figure out if she was laying or not - not entirely knowing what to look for doesn't help. But my heart was soon pounding even harder when I saw this:

TWO large bees at the entranceNot one, but seemingly TWO huge bees at the entrance, one showing an interest in the outside. You might think the size is no big deal, but here's a pic that shows some relative sizes. 

Two large bumblebees alongside normal size workersThis is where the measuring grid I have installed has now come into its own. A typical worker is quoted at 15mm - 20mm in size, though there are many in our nest much smaller than that - e.g. 10mm and last year we had 7mm bumbles. In contrast a queen is typically 25mm.

You can see from the picture below that this bumblebee is easily 25mm - and she's slightly scrunched - I put her nearer 28mm at full stretch. But apart from length, the staggering thing about her size is her width!

measuring the queenHer width poses an interesting question. The queens we saw develop last year were not wide like this - whereas queens in the wild now are moreso, because they've been fattening up to start laying eggs. So, it begs the question - is this an egg-laying queen (e.g. the queen that started this nest) or is this a queen that's been laid. And if so, how come so soon?

Not knowing the answer to this, I was concerned about the desire to show some interest in leaving the nest - and indeed, during the day both of them did. The first did a short 5 second memorisation flight and returned immediately, but that led to a 20 minute soujourn later in the day. I saw no pollen being brought back. Surely they are not going out to look to mate? There are still winter queens looking for nest sites; we're nowhere near laying boys yet (June/July typically)

Now some pics outside the nest:

Queen memorising the nest entranceAnd on the ledge (CH1) - which is nearly 3cm wide (deceptive! I'm going to add measurement markers!)

Queen crawling back into the nest - ducking down to get under the flapI saw both these bumblebees leave and return during the day, but no obvious pollen being collected. (Unlike the workers, who are bringing back plenty). 

So - for now it's a mystery: could two queens somehow have been in the nest from the start? (seems extraordinarily unlikely). Is one a new queen already? Are they both new queens (after all, they both left the nest) - in which case where is our mystery mother? Can't wait to see how this develops!

Other Activity

The morning was very quiet in the nest - it was raining on and off outside, temperature was hovering below 10C and it was very windy, up to 10mph. A handful of small bumbles tried to brave it, most of them turned round immediately and came back in straight away. Two actually hung about in/around the inside entrance most of the day, once braved it on the porch roof above the thermometer and another (see CH1 pic above) actually stayed under the flap!

By 2.30 activity really picked up and they were playing catch up - so despite the ongoing wind there were plently foraging trips. I think some were being a bit foolhardy. In fact around 6pm I ended up rescuing a small worker that seemed to emerge for the first time and instead of going back into the nest, crawled off the ledge and disappeared.

I found her in the grass, warmed her up indoors and managed to get her back on the ledge. She disappeared again and I don't know (until I review the CCTV) whether she went back into the nest or not - I hope so! 

Challenging a good theory

Hard to believe we've had out beepol lodge almost a week! So, it's time for an update. 

It's been a week of cold and changeable weather, so the first few days in particular were not very active. Moreover, our plastic lid was still trapped (loose) inside the nest and we think it was possibly impeding the bumbles a bit from freely leaving the nest. Plus they had to recover from their travel trauma. 

By the weekend I'd cleared the lid and we definitely had some new first flights occuring. That enabled me to calibrate the motion detect on the CCTV and make sure all the tech was working properly. The weather was still a mixture of wet and windy and very cold at night, so we weren't surprised to see much happening, though it was certainly noisy and busy inside the nest itself.

The down-facing camera gives us a great, sharp view and good audio too; so this year I'll be taking some recordings and doing some frequency analysis. 

Monday on the other hand was a different kettle of fish, with a hive of activity - if you don't mind me mixing my metaphors and literals. This was the day that our new borns really decided to go for it. One after the other, time and time after time - almost a stream of babies coming out on their first flight - at times it seemed like one a minute. And returing with pollen too - greyish yellow by the look of it. It was amazing to see them all so busy and carrying out their programming! (incuding their first memorisation flights). 

Two babies - one about to leave, one just performing her first memorisation flight, looking at the nest (top left)

A few were nervous - not sure about pushing on the flap, or not sure about launching off the nest ledge, and either coming back in from flight after 10 seconds or just going back in the nest. A few were not sure about the nest - returning with pollen and then heading back outside with it, before realising the inside was definitely where they were meant to be. 

Some of the tiniest didn't seem to figure out the nest entrace at all - even though it was wedged open - instead scratching at the connecting gap on top of the new wax-protection module. Had they forgotten where they came out? Was their eyesight not so good? Or was the smell of the nest stronger from there? As ever, each observation leads to many questions. 

Here are a few more observations:

A night time we sometimes have a solitary bumblebee standing guard on the front wall of the lodge, here's one tonight - she's been there several hours: 

standing guard over nightUsing our cunning reflective size guide, we can say she is about 12mm long. 

She is by no means the smallest or largest bee in the colony. I've seen one I estimate at about 8mm and have been seeing several large ones tonight. I'm not sure if the largest of these is the queen or not: we'd love to see her. Certainly there is a large bumblebee that moves slower than the others and is seen occasionally doing a tour of the area under the camera. It's her combined size and (slow) speed that makes her stand out. At one point this particular bee paused for a while over the wax pots we can see - was she laying?  I'd love to see that - see what the process is - how and when she lays and how the other bees (presumably) seal the pot. 

This is a very big bumblebee - slightly side on - in the centre of this picture:

could this be our elusive queen?

And look at this tail end at the top of this picture. It's massive - at least twice or thrice the size/width of any of the others:

Or is this our queen's tail?

We think we saw our active queen only once in our Koppert box, this time last year, so we are not sure what her behaviour patterns are and how much of the nest she uses. We think this is probably a good spot though - directly under the infrared heat from the camera - so I wouldn't be surprised if se was to lay something near here. 

Honeypots 

It's a bit of an unintended, but delightful, consequence that the infrared from the camera is providing "catchlights" in the wax pots that contain liquid honey, as this gives us an easy way to identify and count the honey pots over a fixed area. Our friends from Dragonfli posed the question about how the stores get used and we are keen to understand this too. 

This morning when I first looked I could identify 4 - and 90 minutes later only 3. I wondered if one had been consumed giving the inclement weather and lack of foraging activty (very windy this morning). By this evening there were 7 indetifiable catchlights. So, not only had it been apparently refilled, but others made too. 

In the final analysis, however, I think the pot from 9am this morning that seemed to have been consumed was just slightly obscured by a bee - or at least the line of the reflective light was - and so I don't think this pot got used. However, I have seen one bumblebee apparently drinking some honey tonight (not much) but more interestingly another bee spending a good deal of time during the day actually resting over the pot and covering it. 

You can see this top left in the following picture, where the pot at "11 o clock" is obscured. This bee had its belly over the pot, hanging face down over the side (as I write it's doing exactly the same again). I'd love to uncover an explanation for this - it might just be coincidence - i.e. the spot it likes to rest - but one thing that is clear from looking at these pictures is that even with a time gap in between, it (or a sister) has come back and chosen exactly the same spot. 

bumblebee hanging over honey pot at "11 o clock"

Quiet in the night

Another thing we have noticed after the first few evenings of real activity is that night times have become a lot calmer and quieter. At first there was constant activity under the "down" camera almost 24x7, but again, as I look tonight, it's quiet. A few bees are in view resting, but only occasionally does one mooch past. They are resting and keeping warm. There is occasional buzz from a single bee and something we really want to do it uncover any patterns in the sound.

We sometimes hear sustained buzzing from a single bee (occasionally a second) in longish bursts. The we sometimes hear a high pitch squeak in short repetitions of about 1 per second. We wonder if this is associated with hatching?

Certainly the bees can be silent when they choose - as they are doing so tonight - with just the occasional high pitched buzz from somewhere unknown. If we can establish a link between bee size and pitch, then we can start to gauge what size bees are making the sound. Intuitively it seems that small callows trying to emerge from a pot might make a high pitched buzz, but it's pure hypothesis at this stage and remains to be tested/observed. To that end we are recording some of the sound patterns from the nest. 

The change in sound during the day poses the question why?

Certainly when threatened a co-ordinated "fizz" seems designed to ward attackers off and possibly communicate the threat throughout the nest colony. Some noise may be due to fanning - keeping the nest cool. Some of it, of course, may be vibrating to keep the nest warm - although perhaps we'd expect more of that during the night time rather than the day - so that is not a convincing explanation.

So - the question remains, is some of the sound associated with communication? Prevailing theory is no, but we love to challenge a good theory!

A big thanks to Dragonfli (Beepol)

I justed wanted to create a public "thank you" and link back to Dragonfli, who have very kindly listed us on their page of interesting customer projects. We're delighted to be considered of interest. ☺

Dragonfli supply the Beepol hive and lodge that forms the main basis of our bumblebee study, research and of course, enjoyment. They are available between March & August - conditions permitting - and a fascinating addition to the garden, with huge scope for learning and education. 

We've modified our lodge by adding cameras, thermometer and various other useful enhancements (e.g. internal measuring chart). You can find all our beepol related articles here. 

Weekend Catchup (1st Beepol Weekend)

Infrastructure

I made some minor infrastructure modifications this weekend. We noticed that the smaller, new bumblebees didn't seem to find the new wax moth flap system on the lodge as easy as we had hoped, despite it being slightly wedged open with blutac. It was easy for them to leave, but on return we noticed that they showed more interest in trying to get into the nest at the lodge lid join (smell?) rather than via the open flap. I have to say, this is slightly baffling when the entrance hole is easily accessible. 

In order to aid memorisation and detection of the entrance, I added some bright yellow tape and blue marking on the entrance flap, in case its transparency was causing an issue:

modifications to lodge entranceWe'll remove the blutac when there is a sufficient in-flow/out-flow of bees that they can learn from and assist each other working the flap. This way we'll slowly train the.

We also noticed that memorisation procedure was also taking in more of our other features in the garden, particularly the nestboxes and associated features. This stands to reason, since we have created that environment to be highly visible and attractive to queens. I wanted to make sure that we didn't inadvertently confuse our new bumbles; for example, into trying to return to one of the other nest boxes. To that end I painted a clear white line upto our lodge. Last year we painted a runway for fun - but since bumeblebees use linear features and markings for navigation, this clearly has a useful function for them. This should ensure that the bumbles are able to return to the lodge reliably, even if they are a little confused by the flap when they get there!

linear navigation feature for beepol lodge

Queen Catching

The weather has been all over the place this weekend - despite being sunny at times it never got above 11C on saturday and about 7C on Sunday. Nonetheless I went out queen hunting, if only to survey activity. 

• Saturday: captured 1 redtail very quickly 15:45 - and placed in pilkington box. She stayed in the capture tube, so much so I put the whole tube in there! Eventually left the box sunday. (QB2012-12)
• Saturday:  captured a second redtail at 16:30 - she was very placid, probably happy to bed down; went in box 1 very quickly and stayed there still all night, eventually leaving 11am Sunday. She did no memorisation so she won't be back. (QB2012-13)
• Sunday: I went out about 13:30. It had been sunny but, of course, as I left started to drizzle, eventually hail! Didn't think I'd find much but caught (and lost) a redtail, saw another redtail and bufftail and then eventually caught a bufftail. She also went into box 1, but I didn't observe her leaving. (QB2012-14)

QB2012-13 Redtail resting overnightOn saturday I noticed a few bumblebees out resting and also looking for places to rest, rather than nest. The one in this photo took quite a while exploring this piece of ground. I couldn't understand why as it is not good nest-location ground, but in the end she settled down just to rest. I was intrigued to see how she aligned herself with the features on the ground, as if to achieve better camouflage. (stripe lined up with the white/brown twig; thorax in the shadow). Coincidence or camouflage? It's an intriguing question, but I have a strong feeling that bumbles can use their markings as camouflage and I'm trying to collect as much evidence of this as possible. 

resting queen - coincidence or camouflage?

Nest Activity

For the first few days of the hive, activity levels inside seemed high but we had very few bees showing any interest in the outside world. I think some of those that did may have been lost, as we've not seen many return - although to be fair at this stage I'm not fully tracking all exits & return trips. 

There's quite a range of sizes in the nest - small workers at under 10mm ranging up to some that appear to be twice the size. We have seen one or two seemingly enormous bees on the internal camera, which I am still trying to get a good picture of, to establish if we might have seen the queen.

Finally today (Sunday 15th April) we've seen much more interest in the outside world, although they have picked a lousy day for it! (about 6C - 7C, rain and hail showers, and very windy) Nontheless, some of the tiny bumbles have been bringing pollen back, the first time we've seen that.  There still appears to be some confusion about finding the entrance hole, even with the flap wedged up, so we'll just have to keep an eye on that and ensure none get "stranded" outside the nest. 

Here's a wee one performing memorisation on her first flight.

performing memorisation during first flight from beepol lodge

Audio Frequencies

This year I've started sampling audio frequencies under certain situations to see if there is any pattern - it's purely exploratory at the moment. We've found a queen buzzing at almost a perfect middle C3 (130Hz). 

We noticed during the night the colony, while still busy is a lot quietier and when accompanied by crackling sounds (hatching) there is a single sustained note (often 30 seconds or more in length, repeatedly), so far measured at 180Hz.

During the hail storm today, the bumblees went crazy! A high pitched synchronised sustained buzz, almost like a scream, at between 400Hz and 500Hz. We'll do our best to capture more data to determine any patterns.