A Learn about on Bee and Mite Waft: Phase 2

Earlier analysis signifies that varroa mites make the most of drifting and robbing bees to get carried to different hives locally. However there have been nonetheless various exceptional questions on the main points of mite immigration. In need of additional information, in 2018 I undertook an bold find out about to reply to a couple of.

Again in 2018, beekeepers have been speaking about “mite bombs,” and blaming their issues at the immigration of mites from highly-infested neighboring colonies out of doors in their keep an eye on. Ultimate month I reviewed revealed research referring to this phenomenon. However we will have to remember the fact that institutional researchers are ceaselessly below power to “put up or perish.” On this aggressive surroundings, I sadly see a large number of conclusions being drawn from datasets involving a rather small collection of marked bees and hives.

In need of to realize a greater figuring out of bee waft and mite immigration in my very own operation, I determined to run a larger-scale find out about, involving extra colonies, extra marked bees, and bigger distances, with a purpose to assist solution the next 8 questions:

Inquiries to Solution

How a lot mite immigration in reality takes position in past due summer season and fall?
Is mite immigration secure or episodic?
Does mite immigration correlate with robbing?
Do all hives undergo similarly from mite immigration, or are some extra horny to drifting bees?
What quantity of employees from collapsing colonies waft to different hives?
Do increased varroa/virus ranges building up bee waft from a hive?
How a ways do bees from collapsing colonies waft?
How does the waft of bees to within sight hives examine to that of the ones extra far-off?

May I perhaps get solutions to all of the above questions from a unmarried box find out about? Because the satan is all the time in the main points, on this article I’ll cross over how we arrange the find out about.

Fabrics and Strategies

At my house within the dry Sierra Foothills [[1]], we arrange ten “Donor hives” (containing tagged bees) to deliberately cave in from varroa (sadly one collapsed upfront), after which twenty-four “Receiver hives” at more than a few distances to decide the collection of tagged bees drifting into them from the collapsing Donor colonies (Figures 1 & 2).

Placement of the Hives

Fig. 1 The structure of the house backyard, appearing placement of the collapsing Donor hives, in addition to the Receiver Hives from which knowledge for bee waft and mite immigration used to be taken. We’re surrounded through sloping blended oak/pine woodland, with irrigated pasture to the east. My lawn and orchard are in the course of the photograph. The brown dry flooring is how our non-irrigated land seems all the way through the summer season.

Fig. 2 Zooming out, with my house backyard indicated through the golden superstar. We monitored six surrounding apiaries of ours (crimson crosses) for drifted bees. Each and every apiary held round 30 colonies, even supposing best 3 energetic colonies in each and every have been ready as “receivers.”

Learn about design: The above setup allowed us to reply to the questions “How a ways do bees from collapsing colonies waft?” and “How does the waft of bees to within sight hives examine to that of the ones extra far-off?”

Preparation of the Mite Donor Colonies

Following a normal apply of the usage of colonies of “black” or “yellow” bees to spot those who waft, in June we ready two other units of hives with bees of various colours. We requeened the Donor Hives (supposed to cave in) with “yellow” cordovans, and the mite-free Receiver Hives with darkish Carniolans (graciously equipped through queen manufacturers Frank Pendell and Valeri Severson of Strachan Apiaries respectively).

Over the process July we fed the colonies to develop them, boosting them if suitable with combs of high- or low-mite brood. On the finish of July we took mite wash counts once more — probably the most Donors already had counts of 50-100 mites in line with part cup of bees! So we changed some brood combs with the ones from low-mite colonies, and hit them with part a MAQS formic pad, with a purpose to stay them from collapsing sooner than we had the Receiver hives in a position.

Tagging the Bees

It was obvious that because of the swapping of combs, that the black/yellow scoring manner of bees for guardian colony id wasn’t going to paintings, so after reviewing more than a few choice strategies for marking bees, I determined to as an alternative adjust a suave bee-tagging manner advanced years in the past through the creative Dr. Norm Gary [[2]], whom I’ve identified for years, and who used to be glad to assist me with main points. My helper Brooke Molina and I spent the latter part of July and into August perfecting the method, understanding the most productive anesthetization manner, holders for the bees, form of glue, and so forth. (Determine 3).

Fig. 3 We hand-punched over 6000 skinny metal discs and Brooke hand-painted them with other colours for each and every Donor colony, putting them on playing cards coated with double stick tape. The tagging workforce then glued them onto a median of 540 bees in line with colony all the way through each and every Donor’s cave in. Right here’s Alice Dunbar demonstrating how we used a work of plastic with a V-notch (wrapped over with protecting tape) to slip over a bee’s petiole, and harmlessly grasp it nonetheless with its wings out of the best way. We put a drop of Elmer’s quick-drying glue at the stomach, then used forceps to drop and faucet a disc into the glue.

Alice’s husband Brion filmed her tagging bees; you’ll watch her do it at https://youtu.be/2FEeL-O08qA.

Experimental word: After experimentally confirming Dr. Gary’s ideas for disc thickness and diameter, we punched 0.09” diameter discs from 0.010” sheet metal. The painted discs weighed lower than 10 mg — just a fraction of the burden of a load of nectar. We additionally adopted his advice [[3]] that “Label attachment at the stomach turns out preferable to thoracic attachment for a number of causes. There may be much less chance of by chance fouling the wings with adhesive. Moreover, labels have a tendency to break away from the stomach extra simply as a result of there are fewer cuticular setae. The stomach is customized for sporting nectar or water so much that represent the heaviest weights transported through bees. Attachment of rigid steel label to the thorax perhaps might impact flight habits, both through making a balancing downside or through adversely affecting the scutum’s flexibility.” We have been additionally cautious to steer clear of magnetizing the discs, in order to not impact the bees’ magnetoreception all the way through flight [[4]].

For tagging the bees, I customized constructed a chair with an adjustable table to each and every of my helpers’ personal tastes. One of the vital taggers simply liked sitting out of doors and playing the surroundings whilst they glued on tag after tag (Determine 4).

Fig. 4 Right here’s Brooke sitting subsequent to a hive, marking bees. We behaviorally-sorted younger employees to tag through dumping shook bees into the black bottles — the older bees in an instant flew out towards gentle, while younger employees remained inside of within the darkness. The tagger shook out as many bees as they may procedure in a couple of mins into the transparent plastic bottle, after which gave it a shot of CO₂ (the usage of a bicycle tire filler with a hole needle) to in short anesthetize them.

It takes various palms to tag 6000 bees, so along with Brooke and the Dunbars, we have been helped through Anna Mudd. A few of us have been faster at it than others, so I paid my helpers through piece charge (Determine 5).

Fig. 5 Anna have been grafting queens for us so her fine-motor talents have been neatly advanced. I snapped this photograph when she discovered that she may just earn extra in line with hour tagging bees than she’d ever made in any earlier task.

As we glued tags at the bees, we sat subsequent to the hive, with the hive quilt slid in part open, in order that shall we in an instant go back each and every tagged bee again to its colony (Determine 6).

Fig. 6 The taggers in an instant positioned the tagged bees onto the highest bars of the hive from which they’d been taken. The bees temporarily recovered from the anesthetization, walked down onto the combs, and there acted generally.

The Keep watch over Crew

As a way to solution the query “Do increased varroa/virus ranges building up bee waft from a hive?” I had to run tagged mite-free Keep watch over colonies to match their employee waft to that from collapsing colonies. I positioned two handled mite-free Keep watch over hives inside the high-mite Donor crew of hives. Spoiler: As you’ll in the end see, I will have to have run as many Controls as Donors. (Via just right fortune I were given fortunate. Once in a while that occurs).

Preparation of the Mite Receiver Hives

Getting rid of the Mites

As a way to quantify the quantity of mite immigration into the Receiver hives, we copied the technique of Sakofski [[5]], Greatti [[6]], and Frey [[7]], through which they used high-efficacy artificial miticides to get rid of the mite inhabitants in receiver colonies. This permits the advent of just about mite-free colonies (displaying day by day mite drops and mite washes of 0). Power remedy with slow-release miticide strips then reasons any incoming mites (carried through bees) to drop inside of an afternoon onto a stickyboard, offering a rely for mite immigration.

Since we hadn’t used any artificial miticides for over 15 years (and rotate 1 / 4 of our brood combs each and every yr), our mites show off no resistance to experimentally-applied amitraz or fluvalinate, so we utilized the ones two lively elements (Determine 7).

Fig. 7 We began the colonies in April 2018, treating them with oxalic acid, then in June with formic acid, adopted through a mix of Apistan plus Apivar strips.

The ready Receiver hives in the house backyard thus have been mite-free, regularly handled, with stickyboards, scales, and magnetic front traps (Figures 8 & 9). We didn’t position stickyboards or scales at the outyard Receiver hives.

Fig. 8 A Receiver hive in a position to move! I designed the doorway traps so when a drifted tagged bee entered the hive, its metal tag would snap onto the magnet very firmly. I set the doorway top in order that the caught bee may just nonetheless take hold of the ground board with its ft and pull itself freed from the color-coded tag — leaving a transparent document of the bee’s access that shall we then later document with no need to be there to look at the true match.

Magnetic Tag Restoration

After session with Norm Gary, I designed and fabricated magnetic tag retrieval front traps, stepped forward through the usage of super-strong neodymium magnets no longer to be had when he invented the process [[8]] — they labored nice! A magnetic entice positioned on the front of each and every Receiver hive eliminates and holds the tag of any drifted bee that makes an attempt to go into it, permitting us to move out each couple of days and temporarily take away and document any tags from drifted bees at each and every colony front. The wonder, for my functions, of the usage of Dr. Gary’s ferrous tagging method is that it no longer best information the doorway of a drifted bee, but additionally its house colony.

Sensible software: Even supposing state-of-the artwork strategies of monitoring bees with RFID tags or video recording are glorious, Norm’s tried-and-true “old skool” method works extraordinarily neatly and is largely foolproof, because it collects onerous proof within the type of painted discs that may be recovered on the investigator’s comfort, fairly than through sitting in entrance of a hive (or a video) searching for returning bees, or opening the hive and on the lookout for marked bees at the combs. I’m shocked that extra researchers don’t use it!

The Stickyboards

We put in rear-access stickyboards below screened backside forums in all of the Receiver hives in the house backyard (Determine 9). We recorded the collection of dropped mites more or less each 3rd day.

Learn about design: The stickyboard counts of the Receiver hives may just assist us to reply to the next 3 questions:

How a lot mite immigration takes position in past due summer season and fall?

Is mite immigration secure or episodic?

Do all hives undergo similarly from mite immigration, or are some extra horny to drifting bees?

Fig. 9 I make strong stickyboards out of FRP (fiber-reinforced plastic) wall paneling, which can be utilized and reused for years. After counting and recording the collection of mites, we scrape off the adhesive, mites, and hive trash with two strokes of a sheetrock knife. We then re-roll on a mineral oil/ petroleum jelly aggregate with a small-diameter paint curler, and reinsert the stickyboard.

The Hive Scales

As a way to monitor whether or not a Donor colony used to be being robbed, or a Receiver colony used to be robbing different hives, I put Broodminder digital scales below each the Donor and Receiver hives in the house backyard. Because of Wealthy Morris of Broodminder for slicing me a deal at the scales, and for his assist with setup and information processing. I discovered the Broodminder scales to paintings rather well for my functions. I showed that putting a unmarried scale below the entrance finish of the ground board appropriately mirrored general hive weight exchange.

Learn about design: As a way to solution the query of whether or not mite immigration correlates with robbing (in our foothill surroundings), I deliberately carried out this find out about all the way through our late-season nectar dearth (when no weight achieve could be going down). A robbing colony would show off weight achieve, while a colony being robbed would display a weight reduction. The stickyboards would let us decide what number of mites have been getting rides into the hive on any day. Lets then search for correlations.

Format of the Donor hives

Determine 10 displays the structure of the donor and shut Receiver hives.

Fig. 10 The view taking a look south from my again porch. The lengthy arrow issues to our nearest apiary a part mile away. We’re in Northern California, so the considered necessary sun panels and hashish lawn are within the background. The down arrow issues in opposition to my space, with extra Receiver hives some 500 ft away.

OK, I’ve proven how we arrange a find out about to try to download solutions to all 8 our authentic questions. I’ll proceed with our findings subsequent month.

Acknowledgements And an Apology

I very much recognize the assist from my workforce — Brooke Molina, Anna Mudd, and Brion and Alice Dunbar, with out whose assist I may just by no means have pulled this find out about off. Additionally a shout out to Dr. Norman Gary, whose spectacular frame of study has been instrumental to mine.

I once more thank Valerie Severson and Frank Pendell for the queens, and Wealthy Morris for assist with the Broodminder scales.

Ultimate however no longer least I thank the ones beekeepers whose donations assist me quilt the prices of my utilized analysis tasks. That stated, I ask for forgiveness for ready goodbye to put up my effects, however on the time of this undertaking I used to be chastised through a college lab chief who used to be disillusioned that I saved getting the leap on their very own analysis tasks. So out of courtesy I’ve behind schedule presenting my findings till they revealed theirs.

Citations and Notes

[1] GPS coordinates 39.17702, -120.99153, 2880 feet elevation, yellow pine/black oak woodlands.

[2] Gary, N (1971) Magnetic retrieval of ferrous labels in a capture-recapture gadget for honey bees and different bugs. J. Econ. Ent. 64: 961-965.

[3] Ibid.

[4] Liang, CH, et al (2016) Magnetic sensing during the stomach of the honey bee. Sci. Rep. 6: 23657.

[5] Sakofski, F., Koeniger, N., & Fuchs, S. (1990). Seasonality of honey bee colony invasion through Varroa jacobsoni Oud. Apidologie, 21(6), 547-550.

[6] Greatti, M, N Milani & F Nazzi (1992) Reinfestation of an acaricide-treated apiary through Varroa jacobsoni Oud. Experimental & Carried out Acarology 16(4): 279-286.

[7] Frey, E., H Schnell & P Rosenkranz (2011) Invasion of Varroa destructor mites into mite-free honey bee colonies below the managed stipulations of an army coaching space. Magazine of Apicultural Analysis 50(2): 138-144.

[8] Magnet measurement 3 x 6 x 60 mm, set in line in a groove.

A Learn about on Bee Waft and Mite Immigration

Phase 2

Beekeeper-funded utilized analysis – through a beekeeper, for the advantage of beekeepers.

Randy OliverScientificBeekeeping.com

First revealed in ABJ March 2023