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Dave Black

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Dave Black last won the day on August 5 2020

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  • DECA Holder
    Yes
  • Beekeeping Experience
    Hobby Beekeeper

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  • Location
    Bay of Plenty

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Dave Black's Achievements

  1. My experience suggests no-one looks at the document library any more... Crown copyright permits non-commercial use with attribution as long as it is accurate and not disreputable, and they didn't voice any concern when I told them what I did previously.
  2. I haven't read through this thoroughly yet, but perhaps someone can explain this apparent contradiction to me (from the summary)? "Average honey prices paid to New Zealand beekeepers in 2018/19... fell significantly for most honey types apart from monofloral mānuka honey. The value of New Zealand’s pure honey exports increased by 2 percent in 2018/19... with higher export prices (up 10 percent)..."
  3. Like it says on the tin... 2018-Apiculture-monitoring-report.pdf
  4. I'm a little behind in seeking this out, but it's always a useful reference point, and I see 2018 is not there at all so I've added that in a seperate post. These have been made available on the Forum since at least 2012... 2019-Apiculture-monitoring-report.pdf
  5. Varroa have been a part of my beekeeping life forever. In the Forum archives (back to 2012) I have posts whinging about going to beekeeping conferences here and abroad full of promise and short on delivery when it comes to ways of managing the problem, and I retain what I think is a healthy scepticism about what I will call the ‘selective breeding’ route to a solution. From selecting for hygienic behaviour using pin or freeze killed brood assays in the mid-eighties, to the first Bond test (“Live and Let Die”) in 1993, selection for post-capping duration in the mid ‘90’s, and more recent work with VSH and SMR, 40 years of scientific endeavour have led to... well, nothing really. In an Open Access review published this month Matthieu Guichard, Vincent Dietemann, Markus Neuditschko and Benjamin Dainat set out just exactly why this is so difficult. I think it’s a relevant, well written and comprehensive piece and worth reading for anyone at all interested in this aspect of selective breeding. The language is not particularly difficult so it doesn’t require a ‘translation’. Here is their own synopsis: Over the last three decades, numerous selection programs have been initiated to improve the host–parasite relationship and to support honey bee survival in the presence of the parasite without the need for acaricide treatments. Although resistance traits have been included in the selection strategy of honey bees, it has not been possible to globally solve the V. destructor problem. In this study, we review the literature on the reasons that have potentially limited the success of such selection programs. We compile the available information to assess the relevance of selected traits and the potential environmental effects that distort trait expression and colony survival. Limitations to the implementation of these traits in the field are also discussed. Matthieu Guichard, Vincent Dietemann, Markus Neuditschko and Benjamin Dainat, (2020) Advances and perspectives in selecting resistance traits against the parasitic mite Varroa destructor in honey bees. Guichard et al. Genetics, Selection, Evolution, 52:71 doi.org/10.1186/s12711-020-00591-1 https://gsejournal.biomedcentral.com/articles/10.1186/s12711-020-00591-1
  6. Thanks Chris, over at the apiary we hadn't a clue what was going on! Far from the Madd(in)ing Crowd and no romance...
  7. Propolis is a mysterious material, not so much a thing bees produce but literally a collection of ‘things’ they use. Beekeepers view it as a bit of a nuisance and frequently selectively breed honeybees that use as little as possible. In some respects, that’s not a good idea. Apis, euglossine, meliponine, and megachilid bees, and, occasionally, other social insects, all use a kind of propolis to a greater or lesser extent, which in its simplest description consists of plant resins mixed with wax (propolis and cerumen) or mixed with clay or sand soils (geopropolis or batumen). There are plants that use the desirability of these useful resins to attract pollinators but in many, many plants they are just ‘there’ as a part of normal metabolic processes. It is an essential nesting material, but also has some interesting biological activity as well as its physical function. It’s the later that has been the reason for most of the research. It seems Man has always regarded propolis as a therapeutic product, not without reason, and there is plenty of study about its constituents that, so far, seems to have led nowhere. Propolis has been observed to be anti-bacterial, anti-viral, anti-fungal, cytotoxic, anti-inflammatory, anaesthetic, immunomodulatory, and anti-oxidant. Oh, and allergenic, particularly after ingestion. Propolis is quite complex, containing so far at least 300 common phytochemicals, and is never quite the same, varying qualitatively and quantitatively according to exactly where and when it was collected, and by whom, all across the world. Many of these chemicals can be shown to be pharmacologically active, in the right dose even toxic. It’s also true that some are known to have a therapeutic effect for common bee diseases and pests. Unfortunately, it’s also possible to detect less desirable contaminates in propolis, including various classes of residues including pesticides, antibiotics, and heavy metals. At the moment we are never in a position to anticipate its properties or effects and it’s a fair way from being systematically useful because it’s so unpredictable. European honeybees collect the ingredients for propolis from several plant structures where they are actively secreted or exuded from wounds. They can be waxes on leaves or buds, gums and resins from the bark, from fruit, or around trichomes and the ducts of new leaves. In a pinch, even paint, asphalt, and oil. For temperate bees like ours by far the most important sources are the bud exudates from poplars, birch, horse-chestnuts, willow, pine, elm, and alder. I have seen mine working the seed capsules of pittosporums. They collect at any time of year, but mostly while temperatures are warm enough to render the materials malleable. We don’t know how they find sources but the assumption made is that they detect the odour. Resin foraging bees seem to be unoccupied intermediaries between nest construction and foraging, with atrophied wax glands. The geographical dependence of propolis ingredients suggests that New Zealand’s ‘blend’ might be uniquely different and in 1995 Comvita supplied various samples (as tinctures – ethanol extracts) from the North Island (Bay of Plenty, Coromandel, Waikato, Auckland, Taranaki and Northland) to the University of Waikato so they could have a look. They found very little variation between the samples, and actually that they look much like samples from Europe and North America, suggesting that the majority of plant sources were introduced. The only feature of note was that they were all relatively high in some dihydroflaviniods - some of the characteristic phenolic compounds found in nearly all propolis. The problem is that’s a difficult comparison to justify given propolis samples vary so much but it’s interesting if you’re thinking about selling it under a ‘same but better’ banner. It seems to me highly unlikely there is a consistent and reliable difference from anyone else’s honeybee propolis but you never know. There are quite detailed descriptions of collection and use. The majority of bees collecting resin seem to be both collectors and users, swapping roles from time-to-time. A bee will break or scrape a particle or resin off the substrate, pass it along their legs to their corbicula, and then get another. She may hover about the substrate seemingly testing the weight before collecting more. The process may take from seven minutes to an hour before flying back to the hive. There, she will take it to where it is needed and wait to be unloaded by other workers acting as ‘cementing bees’. These bees will take it and apply it, or stash it in a storage area for use later. It can be used to line the nest cavity, reinforce comb, and entomb old pollen or the bodies of invading pests. It doesn’t appear that honeybees modify the material with their own secretions, but other bees do. The cementing bees probably just create an amalgam of the materials available to them. They patrol the nest using their antennae to probe the surfaces testing for gaps that need to be ‘glued’ but how they decide when there is a ‘shortage’ of material, and translate that into a ‘need’ for foragers, is unknown. Resin collectors can be seen dancing at the unloading site (away from the nest entrance and the nectar-forage dancing). The most complete modern description we have of the organisation of propolis use is from Jun Nakamura with Tom Seeley published in 2006 (unfortunately pay-walled). While all honeybees use propolis some strains and races use more or less than others. Apis mellifera caucasia , the Caucasian honeybees from Georgia and Turkey, are notorious for their extensive use of propolis. I had some ligustica from Hawai’i that blocked up most of their entrance each winter. It’s not unusual to find one colony in an apiary that deposits more propolis than its neighbours. Propolis covers small holes and cracks, seals and reinforces the surfaces to which comb is attached, and in a natural nest covers the internal wall in a ‘varnish’ that controls fungal growth and controls water penetration - a propolis ‘envelope’. The most effective demonstration of this that I have seen was and old straw skep hive so completely sealed that it could be filled with water and used as a bucket. Bees in natural nests control the entrance size by restricting it with propolis walls (the word means ‘before the city’ – ‘pro’ -‘polis’ in Greek). Old brood comb incorporates a fair amount of propolis, and in new comb a red/orange tint around the edge of cells can be quite attractive! It’s what makes wax candles slightly yellow and imparts a distinctive scent. When propolis can’t be found bees attempt to collect similar compounds as substitutes. In the comb propolis has been shown to depress the metabolic rates of wax moth adults and larvae, and cause higher larval mortality, and it seems quite clear that it is a significant part of the colony’s general social immunity. The expression of genes related to an individual bee’s immune response is reduced in a propolis-rich environment, probably because the overall bacterial load is reduced, and leaves the bees better able to respond to any additional challenge. While propolis has been shown to have a direct effect suppressing Paenibacillus larvae in a laboratory, it doesn’t appear it would be applicable in a live colony. However, it’s likely in general that the contents stored in combs like honey, brood food, pollen, and larvae, benefit from the addition of propolis and its antimicrobial properties. Although there are some portrayals of honeybees self-medicating with propolis I think these are apochryphal. Honeybees have not been observed either ingesting propolis, or increasing their rate of collection and use in response to disease, although we can increase it by providing a suitably ‘ragged’ surface. Infuriating as it might be, it’s quite clear that propolis use – ‘bee-glue’, is an essential component of naturally healthy honeybee colonies. Further Reading. MC Marcucci (1995), Propolis: chemical composition, biological properties and therapeutic activity. Apidologie 26, 83-99 Vassya S. Bankova, Solange L. De Castro, Maria C. Marcucci (2000), Propolis: recent advances in chemistry and plant origin. Apidologie 31, 3–15 Markham, K.R., et al (1996), HPLC and GC-MS indentification of the major organic constituents in New Zealand propolis. Phytochemistry, Vol. 42, No. 1, pp. 205-211 Jun Nakamura and Thomas D. Seeley (2006), The functional organization of resin work in honeybee colonies. Behav Ecol Sociobiol. 60: 339–349 DOI 10.1007/s00265-006-0170-8 Michael Simone-Finstrom, Marla Spivak (2010), Propolis and bee health: the natural history and significance of resin use by honey bees. Apidologie 41, 295–311 DOI: 10.1051/apido/2010016 Soumaya Touzani, et al, In Vitro Evaluation of the Potential Use of Propolis as a Multitarget Therapeutic Product: Physicochemical Properties, Chemical Composition, and Immunomodulatory, Antibacterial, and Anticancer Properties. Hindawi BioMed Research International, Volume 2019, Article ID 4836378, https://doi.org/10.1155/2019/4836378
  8. Yes. Left-click for synonyms. I must have more faith in the members than you.
  9. The worrying thing is just that this is an extremely difficult question to answer. While I worry, I know that, especially in New Zealand, we know very little about the possible plant-pollinator networks here, and next to nothing about how pollinators are partitioned within the landscape over time. At the moment my reading of the few studies 'worrying' about the local situation is that they point to a possibility, nothing more, and the ones about the situation elsewhere irrelevant.
  10. It's interesting sometimes to back at people's past posts...
  11. If the referendum says so, the Govt will eventually introduce a Bill, subject to the usual public consultation and Select Committee. Once that has Royal Assent, that will create another committee, a Regulatory Authority who, bit by bit, will work out what can and cannot be done. Edibles are way, way down the track. This all takes years; don't hold your breath.
  12. There have been, and are, members from the group that show an interest in providing hives for pollination. It’s not easy, and not a game. This can involve a contractual obligation to provide hives to a written standard on a defined time, and affects someone else’s income too. While most of us can muddle along and manage whatever the bees decide to do, for pollination the beekeeper is definitely in charge, even when the bees disagree. One of the essential skills, useful for beekeeping in general, is the ability to assess a colony’s size or strength, the number of foragers and the amount of brood, and takes you beyond just coping with your bees. Build it into your swarm prevention (so you don’t end up doing swarm control!). On this occasion we had a number of colonies each in three ¾ boxes to open and assess, already disease checked and ‘evened up’. Having an apiary with all the hives at roughly the same stage of development greatly simplifies life. The standard hives are supposed to meet have generally followed the kiwifruit industry and the Kiwifruit Pollination Association (KPA) who were the first in New Zealand to establish some sort of ‘best practice’ approach. Nowadays others like New Zealand Pipfruit and the Avocado Industry Council have done the same. These have all been published on the internet, but for some reason all hide behind a corporate wall and are only available to the privileged few. The basic requirement defines a number of brood frames, and a number of ‘bee covered’ frames to match or exceed, and will then include other aspects like being disease free, or having empty comb-space, management disciplines you should have anyway. For kiwifruit, using full-depth Langstroth frames, the standard requires at least twelve frames completely covered with bees, and four frames that are 100% brood (or seven that are 60% brood). Because someone long ago did the work we know these size frames will be covered by around 2,500 bees, and a properly drawn frame will have about 7000 cells to use for brood or food (when full of food, honey, I count each one as a kilo) and half decent queen can lay around 1000 eggs a day, oh and, there are approximately 10 bees to the gramme. If you remember these numbers, and/or adjust them for your comb size (many of you will use ¾ frames) there are also sorts of things you can hazard a guess at – how heavy your honey boxes are, when your queen will run out of laying room (while you are on holiday), and how many bees you have in your swarm. Put very simply, the idea behind the pollination standard was to use a hive that had enough workers to be foraging for pollen sufficiently well to fund its growth into a honey gathering hive, a hive with about 30,000 bees that will grow by at least another 20,000. Twelve frames of bees (x 2,500 = 30,000) and four full brood frames (x 7000 = 28,000). So how do we look at a hive and guess the numbers? Without all the nuance it’s simple. Smoke the hive gently, look under the cover and count the gaps between the frames that are full of bees (the ‘seams’). Pull the top box forward slightly so you can tip on its end without it sliding off, and looking at the bottom of the top box, count the full seams. Add both numbers together and divide by two. Take the box off, look at the next box, count the seams, tip it, count the seams again and divide by two. Add the seam count for both boxes together and multiply by 2,500. That’s how many adult bees you have. I know, it’s an estimate. If you wanted to know the nuance, to count your brood frames, or know what to do with weak or strong hives, you had to be there.
  13. Do you beekeepers not want a 'Bee Aware' week then? ?
  14. Yes, I read that, and I couldn't think of anything to say about it either. I just can't...
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