APIARIST’S OPINION: JOHN BERRY
‘Overstocking’ or ‘overcrowding’ are well worn terms around New Zealand beekeeping, especially following the boom in hive numbers associated with the 2010s. Now, after a period of industry consolidation, the pressure is less in some areas, but still a huge threat to hive health in many others. Veteran beekeeper John Berry explains what effect overstocking with beehives in an area has on bees, how to best manage against the threats and, who is to blame…
By John Berry
Because of the very nature of bees there will always be times when there are not enough floral resources available to the bees no matter how few hives there are in an area. This is why they store honey and pollen. What we always used to aim for was the optimal number of hives in an average season. The optimal number is often nowhere near the number of hives that can be sustained at the peak of an above average honey flow but by keeping hive numbers down to this optimal level on average you end up feeding a lot less, having healthier and stronger hives and producing far more honey per hive.
It takes energy i.e., honey for a bee to fly. As they fly further they use more honey to fuel the flight and return with less. Long flights also take longer, wear the bees out more which reduces their longevity and increases their mortality risk. Bees will fly for at least 8km to get to really desirable nectar sources, but they do so much better if they don’t have to.
The more work a bee has to do, the quicker it will die.
Overstocking of course just doesn’t apply to honey bees, native and honey bees can have a severe effect on each other and in autumn the buildup of multitudinous insects ranging from wasps to butterflies often end with all available nectar being taken before bees can even get a look in. I was looking at some dandelions in my lawn the other day and saw one honey bee and five dunny bees (a type of hover fly that looks like a bee).
Extending the Flow
Every year is of course different, but, when hives are kept at an optimal level, you often end up with an early box of honey before the main flow starts and an extra box of honey after the main flow. The main flow will also be extended at both ends because those early and late flowers can still provide a good flow providing there aren’t too many bees. The average honey crop per hive in New Zealand is now somewhere south of 30kg which is plain embarrassing. My 10 year-year average is over 50kg. There must be beekeepers out there producing almost nothing on an annual basis because of overstocking.
Weather of course has a huge effect on honey production and hive health for that matter and certainly in Hawke’s Bay this year it has been unrelentingly awful all season, but in other years when the sun has shined it’s not that unusual for me to get over 100kg per hive in some apiaries and a friend of mine who I set up with a nice hive on Bluff Hill in Napier produced 200kg from that one hive in one year. This came from a combination of a beautiful sheltered warm site, year-round sources of nectar from what is a heavily planted urban area with thousands of flowering trees and shrubs, plus, in those days, an almost total lack of competition from other hives. I mention this not to try and show that one hive is the optimum number – which it isn’t – but just to show how much potential is out there if we don’t screw it up.
Getting the Numbers Right
Working out the correct number of hives is a combination of accurate record keeping, local knowledge and trial and error. Different types of country will support different numbers of hives. In my case a lot of this had already been worked out by my father and my grandfather, although the increase in the price of mānuka did lead me to increase both my number of apiaries in mānuka areas and, in many cases, the number of hives in each apiary.
When prices are high you can get more honey off an area by having more hives, but you will get less per-hive. Increase hive numbers enough and you can end up getting less honey than you would have to start with. It is far more profitable to get 60kg per-hive off 100 hives than to get 20kg per hive from 300, and a lot less work.
If an apiary produced above average for the area it was in, or a higher-priced honey, then we would look at adding some hives, but this was always done in a gradual process and it would be very unusual for us to increase an apiary by more than 25% in one year and not that unusual to end up putting it back to the old numbers if crops dropped significantly. As mentioned, every year is of course different, but when you have a lot of apiaries in one area it is quite easy to compare like with like.
We like to have our apiaries at least 3km apart. Some beekeepers controlled numbers by adding more apiaries rather than increasing hive numbers and this has both advantages and disadvantages.
The bigger the apiary the more likely you are to have trouble with robbing, drifting and suboptimal mating. On the other hand, it can be easier to get the work done and it is not always possible to find good sites. 16 hives was the minimum number that I considered economic and these sites tended to be in the dry pasture areas of Hawke’s Bay. Higher rainfall areas tended to be able to sustain 24 or even 32 hives, while the very best mixed pasture/bush sites could handle up to 50.
I believe there are some honeydew sites in the South Island that produce well with a lot more hives than that, but there are also some areas of Canterbury where sites are normally considerably less than 16 hives.
Know Your Area
There are also some areas which are just not worth having hives in because, on average, they produce poor crops. Some of these areas are too dry and some are too wet. One of my regular tramping spots in the Ruahine mountains is accessed through a farm with wonderful clover and a pretty good swath of mānuka and every few years someone tries putting hives up there. It is one of the wettest places I know and for some reason it rains almost daily, even in the worst droughts. Come out a couple of kilometres and it is worth having bees.
Anywhere with wind farms is also going to be pretty doubtful country.
When varroa came along I noticed a good increase in average honey production, especially in dry areas near river beds where there were previously large numbers of feral hives in the hollow willow trees. The best of these apiaries were achieving a 10-year average of over 100kg per hive, but then beekeeping took off in popularity and these sites were overrun with large apiaries of hives destined for the mānuka in the mountains. These hives were on-site for generally 10 and a half months of the year leading to a drastic reduction in crops and a big increase in both spring and autumn feeding. Even when the surrounding hives were gone for that one and a half months, the hives were not in as good an order as normal because of the bees having to fly huge distances to get anything during the rest of the year.
Grossly overstocking an area affects every hive within about 8km. Even urban areas around here have been heavily affected both with mānuka hives and a big increase in hobbyists. Urban areas are mostly roof, lawns and roads and it doesn’t take much to over stock these areas. 20 extra hives in an area means an extra million mouths to feed and that takes tens of millions of flowers.
The Ramifications
The recent price drops for all types of honey has brought home, quite forcibly, to a lot of people the effect of overstocking and these effects have been felt both by new beekeepers desperate for somewhere to put their hives, and established beekeepers who have found their costs and workloads have increased while their honey production has dropped, in some cases well below the point of viability. I know both new beekeepers and old established beekeepers who have just walked away.
Who, or What, is to Blame?
Established beekeepers who increased hive numbers when beekeeping finally became profitable. New beekeepers who saw a chance to make an independent living. Corporate businesses that could see dollar signs. Lending institutions who couldn’t tell the difference between hype and reality. Landowners wanting their own piece of the pie.
Tertiary institutes training people in beekeeping for jobs that were often not there and in even more cases training people that would never be physically able to do beekeeping.
All the hype around bees and honey causing more people to become interested in bees and leading to a huge increase in the number of hobbyists, some of whom enjoyed it so much they went on to become commercial beekeepers.
An ever-decreasing amount of land suitable for beekeeping due to afforestation and also scrub areas slowly returning to bush. Increased demand for pollination hives both real and projected.
MPI’s role
All of the above have certainly had an affect and would have had some affect no matter how things happened, but the Ministry for Primary Industries (MPI) need to shoulder a lot of the blame for their enthusiastic encouragement to increase hive numbers without giving any thought as to where these hives would go and what impact these hives would have on existing beekeepers. Unbelievably to me, they were still pushing the same line with great enthusiasm at our latest conference.
Some of their crazy figures on the increased number of hives needed for pollination on crops that didn’t eventuate didn’t help either.
MPI don’t go around telling farmers that they can run three times the number of dairy cows on a farm, or three times the number of sheep, but for some reason they thought this would be fine for beehives.
Hive numbers are starting to return to more sustainable levels, but there have been a lot of casualties amongst all classes of beekeepers.
Worst of all
Perhaps the saddest for me is the loss of trust and respect that beekeepers used to have for each other and the cooperation and free sharing of knowledge that was part of being in the beekeeping community. These things can still be found between beekeeping friends, but are no longer almost universal like they once were and knowledge is shared a lot more carefully because of the potential consequences of that knowledge being used against you.
John Berry is a third-generation commercial beekeeper in the Hawke’s Bay and a former chairman of his local branch of the National Beekeepers Association. Having spent 50 years fulltime in the hives, his Berry Bees business has been recently downsized to about 30 hives.
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