A Learn about on Bee Go with the flow and Mite Immigration: Phase 3

Closing month I confirmed how we arrange a box learn about to take a look at to reply to a variety of questions on mite go with the flow from collapsing colonies. Let’s proceed.

The Donor Colonies

We had arrange two mite-free Regulate Donor hives, and 9 high-mite Donor hives supposed to cave in (the 10th collapsed ahead of we have been able). Colony strengths averaged 9 frames coated with bees (vary 7-13). Beginning varroa mite infestation charges of the high-mite Donors (decided via alcohol wash) averaged 26 mites (vary 11-55, in step with stage part cup of bees [[1]]).

Tagging

At first of the learn about on 17 September, we glued color-coded metal tags onto 50 non-flying bees in every hive, after which later tagged further cohorts of bees (100-250 at a time) when their colony’s mite depend exceeded 30, or we noticed indicators that cave in was once impending (lack of power, deformed wings, or demise pupae). In some Donors that collapsed slowly, we tagged further bees all through the method. In all, we tagged a complete of 6230 bees, averaging 585 in step with hive.

Effects and Dialogue

Did the Tagged Bees Behave Usually?

I confirmed closing month how we evenly anesthetized and tagged the bees. A vital query to believe is whether or not the method of tagging the ones bees modified their behaviors. So I watched them heavily afterwards (Determine 1).

A Learn about on Bee Go with the flow and Mite Immigration: Phase 3

Fig. 1 We tagged staff shaken from brood combs, after which behaviorally-sorted to acquire non-flying, possibly “younger” bees. Checking again within the days after making use of the tags, the tagged bees gave the look to be behaving like “standard space bees” at the combs, as on this photograph.

What was once placing was once that within the first days after the preliminary tagging, we didn’t see any tagged bees on the entrances or flying. However after round 10 days, we have been stunned via seeing tagged bees unexpectedly seem en masse on the front — possibly as they shifted from nursing conduct to guarding and foraging (Determine 2).

Fig. 2 What a marvel to come back out to the Donor backyard in the future and notice the tagged bees unexpectedly appearing themselves, displaying “standard” development in conduct. It was once in point of fact conspicuous and ambitious! This showed that we have been tagging cohorts of bees of identical behavioral “age.”

After which a couple of days later, we spotted tagged bees performing as foragers (Determine 3)

Fig. 3 I watched a unmarried red-tagged bee display up at some pollen that I had spilled, after which it seems that recruit different foragers with the similar tag colour. I additionally noticed tagged bees foraging upon spilled syrup the place we fill our feeder jars. All indications have been that the tagged bees have been behaving totally typically.

Development of the Colonies

The Donors: The 2 mite-free Regulate Donor colonies retained their power and well being right through the 74 days of knowledge assortment.

The entire high-mite Donor colonies save one, in the future collapsed (D7 most effective dwindled slightly). Some started collapsing in September, however maximum did so all through mid-October. Some colonies collapsed reasonably temporarily, others extra slowly.

The Receivers: All Receiver colonies remained in just right well being. The ones in the house backyard with stickyboards maintained mite wash counts of 0 right through the learn about, instead of 4 that had counts of one all through the height of bee go with the flow on 15 October.

Answering our Questions

We had a variety of questions to reply to; let’s move over them separately.

Query: What share of staff from collapsing colonies go with the flow to different hives?

This is among the number one questions that this learn about was once designed to reply to.

Observations from the Donor Hives

It temporarily turned into transparent that staff go with the flow freely between within sight hives (the Donors have been a number of toes excluding every different) (Determine 4).

Fig. 4 There was once really extensive go with the flow of tagged bees between the Donor hives, as evidenced via bees with other tag colours appearing up at the combs, as within the photograph above. However since the ones hives didn’t have magnetic traps, shall we no longer quantify the total quantity of drifting going down.

At ultimate cleanup on the finish of the learn about, we recovered 44 drifted tags from the ground forums or flooring in entrance of the Donors (2-13 tags in step with hive, with the drifted tags incessantly from probably the most closely-adjacent colonies). That works out to twenty% of all tags recovered, confirming that there’s numerous go with the flow between within sight hives.

Experimental limitation: The ones 44 recovered tags can also be regarded as as a gross underestimate of what number of tagged bees in reality drifted into within sight Donors, because the Donor hives didn’t have magnetic traps. Any drifted bee would possibly have later flown out to die with out leaving a tag in the back of (as evidenced via the reality that there have been only a few tagged bees or dropped tags final within the Donor hives on the finish of the learn about).

Earlier research have discovered that charges of employee bee go with the flow between within sight hives can also be as much as 40% [[2]^{, [3], [4], [5], [6]}], however has been extra most often been discovered to be within the 3-10% vary. On this learn about we recovered drifted tags from 3.6% of our tagged bees (Desk 1), however I’ll give an explanation for in a second why that may be assumed to be an underestimate of the particular quantity of go with the flow that happened all through this learn about.

Desk 1. Of the 6430 tags that we glued onto younger staff, we recovered 3.6%, most commonly from the magnetic traps of the Receiver hives, but in addition some from the ground forums and flooring in entrance of the Donor hives. I’ll move over this knowledge graphically additional alongside.

It’s an open query as to the place the 6000 unrecovered tags (and their bees) wound up. The tagged bees will have drifted to colonies no longer concerned within the learn about, or simply ultimately died within the box, as do nearly all of staff.

We will justifiably suppose that our depend is an irony of tangible go with the flow, is since we had magnetic traps on most effective 3 of the 30 hives in every of our surrounding outyards, so would most effective be expecting to recuperate 10% of the drifted bees to these yards. In a similar fashion, we don’t understand how a lot of every cohort of tagged bees drifted into unknown hobbyist or feral colonies in the community.

Conclusions: Bees did certainly go with the flow from collapsing colonies, but in addition from mite-free hives. Our quantified 3.6% drifted tag restoration charge can also be safely assumed to be a considerable underestimate of the particular proportion of tagged bees that drifted from our Donors to different colonies.

Correlation With Varroa Infestation

Query: Does the varroa-virus complicated build up the velocity of bee go with the flow into different hives?

Even supposing a variety of parasites had been proven to have an effect on host conduct with a view to build up transmission, there’s very little proof to this point that both varroa or DWV [[7]] induce higher drifting of honey bees [[8]].

So since this wasn’t a number one query to reply to, in designing this learn about I integrated most effective two mite-free Regulate Donors, erroneously assuming that their go with the flow charges could be identical. I may just no longer had been extra fallacious! (Determine 5).

Fig. 5 It became out that of the entire Donors, the 2 mite-free Controls exhibited no longer most effective the bottom, but in addition the perfect charge of go with the flow! The charges of go with the flow from the 9 varroa-collapsing Donors all fell between that of the 2 mite-free Controls.

Looking back I want that I had run a bigger collection of mite-free Controls, and thank my fortunate stars that I didn’t run just one, since drawing conclusions from the knowledge of both Regulate on my own would had been very deceptive. Thankfully, those two Donor hives confirmed us how very much the velocity of bee go with the flow can range between wholesome colonies.

Nonetheless curious, and because we did take periodic mite washes from the Donor colonies, I additionally regarded to look whether or not there was once a correlation between the depth of the varroa infestation charge, and the level of drifting (Determine 6).

Fig. 6 I didn’t plan in particular to create this graph, so used mite wash knowledge taken from our 15 October washes, or the mid-September mite counts from two Donors that had already in large part collapsed via that later date. Once more, there was once no obvious correlation between varroa infestation charge and the velocity of bee go with the flow.

I’m no longer about to make any statistical declare based totally upon an “n” of most effective two hives within the Regulate crew, however our effects exemplify this sort of “unsightly information” that Thomas Huxley was once regarding in his well-known quote: “The good tragedy of science — the slaying of an attractive speculation via an unpleasant reality.”

Conclusions: It might make “general sense” for the varroa-DWV complicated to motive inflamed bees to go with the flow to different hives. However, as discovered via others, our box knowledge don’t beef up that beguiling speculation.

Tag Restoration via Date

Even though the varroa-DWV complicated isn’t the motive, that doesn’t essentially imply that employee bees don’t generally tend to extend their quantity of drifting as their colony collapses. Loose [[9]] discovered that:

A person bee is much more likely to go with the flow from a small to a big colony than vice versa.

We noticed that two Donors collapsed in a while after the beginning of the learn about, while lots of the relaxation collapsed in mid-October. Let’s see whether or not that’s mirrored via tag restoration (Determine 7).

Fig. 7 The restoration of tags correlated beautiful heavily with the collapses of 2 colonies in overdue September, after which with the remainder of the Donors in in mid-October.

The above knowledge indubitably recommend that bee go with the flow correlates with the timing of colonies collapsing, so let’s take a more in-depth take a look at our restoration of drifted tags, Donor-by-Donor.

Timelines of Restoration of Drifted Bees

My predicament when designing and executing this learn about

Remember the fact that this learn about was once about mite immigration, and we’re taking a look at bee go with the flow within the context that immigrated mites would wish to have stuck rides on both drifting or robbing bees [[10]]. From different research, in addition to my very own observations, I suspected that really extensive mite immigration because of drifting bees may happen from September via November in my space. That covers a 90-day timespan. However employee bees all through that point of season are living for a median of most effective about 35 days [[11]^{, [12], [13]}], so I didn’t need to mark all 500 bees originally of the learn about, since many may no longer nonetheless be alive by the point that their colony in reality collapsed.

Another design would had been to arrange equivalent numbers of mite-free and high-mite Donors, and at the similar day of every week, tag 50 bees in every hive, concurrently grading every colony for power, after which search for a correlation between lack of power and bee go with the flow. However since I don’t have grad scholars at my disposal, the logistics would had been tricky. Of higher significance, there would had been smaller numbers of tagged bees in a hive at time of cave in, and my function was once to center of attention upon acquiring probably the most conceivable knowledge at the drifting of staff all through the time of tangible cave in. That stated, I strongly inspire somebody to run the learn about described!

Did the act of tagging bees make them go with the flow?

Every other query arises comes from observations via a variety of different researchers that bees marked in a while after emergence would possibly showcase excessive charges of “loss” throughout the first days after being marked. This made me curious as as to whether the ones “losses” are an artifact of one thing do with the method or marking them (which might have confounded our knowledge), or whether or not that early lack of tagged bees was once merely because of them getting at a loss for words and drifting all through their first defecation flights.

On this challenge, all through the 5-day length between 17 and 21 September, we glued tags onto over 3000 staff, checking the magnetic traps at the Receivers each day. Right through this period of time we recovered just a unmarried tag the day after our preliminary tagging of 550 bees, and most effective 2 extra drifted tags during the twenty first. We then took the weekend off, and checked the traps on 24 September, after we recovered 17 drifted tags.

Conclusion: The above findings recommend that the way by which we tagged bees didn’t start up fast drifting.

Relevance to Mite Immigration

I’ve showed that shaken non-flying “space bees” (akin to we tagged) generally tend to showcase a better charge of mite infestation in comparison to “flyers” [[14]]. That is possibly because of the statement that nurse bees are most fascinating to varroa, and thus have the perfect infestation charge of any staff within the hive.

So at what age would we predict bees to generally tend to go with the flow? Once more returning to King’s observations in 1932:

The ages at which drifting gave the look to be maximum prevalent have been between the 5th and 10th days, which corresponds somewhat heavily with the age at which younger bees display an inclination to shift from actions throughout the colony to box paintings.

Loose [[15]] adopted up in this in 1958, discovering that:

Lots of the bees which go with the flow achieve this all through their orientation flights and ahead of they turn out to be common foragers.
Bees rising in August and September go with the flow lower than the ones rising previous within the 12 months.
Drifting varies significantly in numerous cases, and could also be intensive.
Drones go with the flow two to 3 instances as often as staff.

And in any case, Bordier [[16]], monitoring 1000 tagged bees with a receiver hive positioned to both sides, discovered that 10% of them drifted to some other hive, most commonly once they have been over 10 days of age.

We didn’t in particular arrange this learn about to resolve age of go with the flow, however since we most effective tagged bees that didn’t fly off after shaking them from the combs, we will most probably suppose that they have been younger “space bees.”

Sensible utility: For the reason that factor of passion is switch of varroa by way of drifting, if we’re looking to correlate mite immigration with bee go with the flow, it’s essential to grasp the behavioral “age” of the ones drifted bees. Is it principally younger staff getting misplaced all through cleaning or orientation flights, foragers getting back from their first exploratory flights, or older foragers that both were given misplaced, disoriented, at a loss for words, or not able to withstand the alluring smell of some other colony?

So with the above caveats and packages defined, let’s see what we will tease out of our knowledge. I’ve created graphs of tag utility and restoration for every person Donor colony, with the date and collection of bees that we tagged in blue columns (at the left hand y axis), and the collection of their tags magnetically recovered in Receiver hives in crimson columns (on a distinct scale at the proper axis). The columns don’t come with drifted tags later recovered from Donor hives.

Query: At what age do bees generally tend to go with the flow?

We tagged bees within the mite-free Regulate Donor hives most effective within the first few days, which provides us a chance to get an concept of at what ages the ones bees drifted from the ones wholesome colonies (Determine 8).

Fig. 8 Those first two graphs are for the 2 mite-free Regulate Donor hives, by which we tagged bees most effective within the first few days (the blue columns). As I’ve already stated, C2 then exhibited way more drifting (the crimson columns) than did C1 (and a better quantity in a while after tagging). Colony-to-colony variation is at all times the bugaboo of box analysis!

Interpretation: The quantity of drifting of bees from the 2 Regulate Donor colonies was once as other as night time and day, however the total timing of bee go with the flow was once smartly unfold out for each colonies — indicating that the tagged bees drifted in any respect other ages. Strangely, we recovered a tag from every colony at the 70^th day after first tagging, this means that that even very outdated staff would possibly go with the flow.

Now let’s transfer to the high-mite Donors.

Query: Does bee go with the flow correlate with the cave in of a hive?

Word: This learn about was once designed to quantify the level of drifting as colonies collapsed, no longer the correlation between collapsing and drifting. In those colonies, the correlation of go with the flow with age or cave in could also be confounded via our tagging of extra bees through the years. Looking back, if I have been to run this learn about once more, based totally upon the unevenness of go with the flow from the Controls above, I may most effective tag bees all through the primary week, somewhat than looking ahead to their colonies to start collapsing.

That stated, I nonetheless to find it of passion to seem heavily on the knowledge. Versus the mite-free Controls above, all however one of the crucial high-mite Donors did cave in. In every of the ones Donors, we tagged 50 bees to begin with, however then waited, if vital, for indicators that the colony was once collapsing (reducing power, deformed wings, or demise pupae) to tag some other 450 (or extra) bees. You’ll inform after we idea that cave in regarded impending via the timing of the extra blue columns.

Because of the trouble in making a three-axis graph in Excel, I’ll supply beginning and different suitable mite wash counts within the captions. Take your time in inspecting the graphs beneath (and the ideas within the captions), as they let us know so much in regards to the drifting of bees all through a colony’s cave in because of varroa.

Fig. 9 Remember the fact that the scales for the blue and crimson columns are other. D1 began with a excessive mite depend (30) and we anticipated it to cave in temporarily, however it didn’t get started to take action till mid-October, after which did temporarily. D2 began with a reasonably low mite depend (19), and was once nonetheless robust on 1 October, however then was once collapsing temporarily via 15 October, with a mite depend of 51. D3 began with excessive mites (33), and likewise crashed via mid-October. Of passion, it graded at just a quarter body of bees on 31 October, but 3 of its tagged bees drifted all through November (most likely from a 2d drifting from some other Donor?). D4 began with a low mite depend (11), was once nonetheless robust on 1 October with a wash depend of 29, however then collapsed slowly.

Interpretation: The clumpings of the crimson columns for those colonies recommend that bee go with the flow was once related to cave in, even if some colonies collapsed extra temporarily than others.

Fig. 10 Mite counts higher temporarily in D5 (from 15 to 53 via 15 Oct) and it collapsed all through the closing part of October, while D6 was once a powerful hive with an overly excessive beginning mite depend (55) that we rushed to tag because it began collapsing in September. D7 (beginning depend of 13) by no means collapsed, so we tagged most effective about part as many bees as for the remainder of the Donors. D8 (beginning depend 38) collapsed quite early, while D9 began robust and with a reasonably low mite stage (17) that higher very much via mid-October (45) , inflicting indicators of PMS (whilst it nonetheless contained 6 frames of bees). On account of its extended cave in (3 frames of bees final on 31 Oct), we tagged some other 500 bees on 2 November.

Conclusion: Even though our knowledge didn’t beef up that mite-infested bees essentially go with the flow greater than “standard,” it does seem that higher go with the flow incessantly coincides with the timing of cave in. It’s no longer transparent whether or not that was once simply an artifact of our timing of marking, or because of bees tending to go with the flow out of weakening colonies “with issues” into extra sexy colonies.

I’ve most effective simply begun — subsequent month we’ll check out the impact of distance upon drifting bees, the “good looks” of a few colonies to drifted bees, after which directly to our knowledge at the immigration of mites into the Receiver hives, relative to incoming drifted bees. I’ll then proceed with quantifying the true quantity of mite immigration, and whether or not there was once a correlation with robbing. As I stated, this was once an bold learn about, and we will be informed so much from it!

Acknowledgements

Because of my helpers Brooke Molina, Anna Mudd, Sandy Honigsberg, and Brion and Alice Dunbar, with out whose assist I may just by no means have pulled off this learn about. And Dr. Norman Gary for his useful session. And naturally to these beekeepers whose donations allow me to pay for doing this type of analysis.

Citations and Notes

[1] All mite counts on this article are for the collection of mites recovered via a mechanically-agitated alcohol wash of a degree part cup of bees

[2] King, GE (1932) Drifting bees would possibly make manufacturing information of little price. Am. Bee J. 72: 141-142.

[3] Nelson, DL & SC Jay (1989). The impact of colony relocation on loss and disorientation of honeybees. Apidologie 20(3): 245-250.

[4] Jay, SC (1969). Drifting honeybees in industrial apiaries v. Impact of drifting on honey manufacturing. Magazine of Apicultural Analysis 8(1): 13-17.

[5] Pfeiffer, Okay & Okay Crailsheim (1998). Drifting of honeybees. Insectes Sociaux 45: 151-167.

[6] Goodwin, R, et al (2006) Go with the flow of Varroa destructor-infested employee honey bees to neighbouring colonies. Magazine of Apicultural Analysis 45:((3) 155-156.

[7] Deformed Wing Virus.

[8] Citations in Phase 1 of this sequence.

[9] Loose, JB (1958) The drifting of honey-bees. The Magazine of Agricultural Science 51(3): 294-306.

[10] Ignoring for now that from drifting drones. Right through the process this learn about, there have been only a few drones in any of our colonies.

[11] Lloyd Harris, in prep.

[12] Loose, J & Y Spencer‐Sales space (1959). The longevity of employee honey bees (Apis mellifera). In Court cases of the Royal Entomological Society of London. Collection A, Common Entomology 34 (10‐12):141-150.

[13] Sakagami, S& H Fukuda (1968) Existence tables for employee honeybees. Inhabitants Ecology 10(2): 127-139.

[14] https://scientificbeekeeping.com/re-evaluating-varroa-monitoring-part-4/

[15] Loose, JB (1958) op cit.

[16] Bordier, C, et al (2017) Must I keep or must I’m going: honeybee drifting behaviour as a serve as of parasitism. Apidologie 48(3): 286–297.

A Learn about on Bee Go with the flow and Mite Immigration: Phase 3

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