Supply of and Demand for Pollination Hives In New Zealand

Transcription

1 Supply of and Demand for Pollination Hives In New Zealand A briefing paper prepared for the Strategic Pollination Group Acknowledgements The authors would like to thank the MAF Sustainable Farming Fund and pollination industry related sectors for providing the funding for this briefing paper. We also acknowledge the beekeepers and the industry representatives who responded to the surveys underpinning this work. Authors Dr Mark Goodwin has 25 years of experience in honey bee and pollination research. Mark leads the HortResearch honey bee research team based in Hamilton which carries out most of the honey bee research in New Zealand. The team also conducts research on the effect of pesticides on bees, provides disease diagnostic services for the New Zealand beekeeping industry and conducts research on the pollination of a range off crops in New Zealand and other countries. Sandy Scarrow is a horticultural consultant with Fruition Horticulture (BOP) Ltd a company she part owns. She was previously with Agriculture New Zealand and MAF in Whakatane before shifting to Tauranga. She works closely with the kiwifruit and avocado industries and has involvement with other projects relevant to primary producers. Michelle Taylor is an apicultural scientist with HortResearch. Michelle has been closely involved with the beekeeping industries in both New Zealand and the United States of America for the past nine years. Currently she is involved with the programme designed to develop technologies for the control of varroa to ensure that enough insect pollinators remain in New Zealand s environment.

2 Table of contents OVERVIEW... 1 INTRODUCTION... 2 CHANGES IN PLANTED AREA... 4 Hives used in pollination... 4 Demand for hives between the North and the South Island... 7 Availability of additional hives... 9 Trends in beekeeper numbers and hive numbers in the North and South Island 10 Beekeeper numbers Honey bee hive numbers Managed colonies Feral colonies ADDITIONAL THREATS TO HIVE SUPPLIES ) Future effects of varroa ) Toxic Honey ) Plant alkaloids ) Exotic pests and diseases of honey bees European foulbrood Small hive beetle Tracheal mite Tropilaelaps Africanised bees Cape Honey Bee CONCLUSIONS APPENDIX APPENDIX APPENDIX APPENDIX

3 OVERVIEW Pollination of most flowering plants in New Zealand, with the exception of grass species, occurs either partly or fully by insect activity. Of all insects, honey bees are the most effective pollinators of commercial crops as their population per colony is far larger than any other pollinator species. Although introduced bumble bees, native solitary bees, flies, wasps and other insects contribute to pollination, they cannot be relied upon as they have insufficient numbers or they are not always present. Without honey bees most of our horticultural and cropping industries would no longer be economically viable. The persistence of clover in pasture, especially with the additional pressure of clover root weevil may also be compromised. Currently, the peak demand for pollination hives occurs in November when an estimated 88,675 hives are required for pollination. Of this peak, 78% of the hives are required in the North Island. With the anticipated increase in crop plantings, it is estimated that the peak number of hives required in November will lift to 103,150 hives in 2010 and 108,675 in Approximately 80% of these hives are required in the North Island. Whilst the requirement for honey bee pollination of crops has been increasing, the number of beekeepers and the number of beehives in New Zealand has steadily been declining. Since the introduction of varroa to the North Island almost all feral colonies and at least 20% of the managed colonies in the upper North Island, where varroa has been the longest, have disappeared. Based on experiences from countries where varroa has been present for longer than New Zealand, larger declines in hive numbers are to be expected. This is mainly due to varroa developing resistance to the control chemicals currently in use. In 2005 the USA imported hives from Australia to pollinate their almond crops due to the insufficient supply of USA hives. When hive supplies become insufficient for pollination in New Zealand, live bees cannot be imported because of the risk of importing honey bee pests and diseases currently not present in New Zealand. Additional circumstances that may further erode hive numbers include the introduction of additional honey bee pests to New Zealand. Observations of their worldwide spread indicate that it is only a matter of time before they are found in New Zealand. There are also a number of plant compounds that if found in honey may have an adverse effect on the honey market. Perhaps the largest threat to the availability of hives is economics. World honey prices are currently declining and may decline to such a level that many beekeeping operations will no longer be profitable. This will have the largest impact on beekeeping operations whose major source of income is clover based honey production. However, beekeepers providing pollination services will also be affected as almost all of them gain some income from honey production. If honey prices were to reduce to the level in 2000, beekeepers predict that hive numbers will reduce by at least 25%. The increasing demand for managed hives for pollination is likely to put considerable pressure on hive supplies and increase prices. Whether this is sufficient to encourage beekeepers to increase the number of hives they use for pollination or attract new beekeepers to the industry is unknown. 1

4 INTRODUCTION Pollination of most flowering plants in New Zealand, with the exception of grass species, occurs either partly or fully by insect activity. Of all insects, honey bees (Apis mellifera) are the most effective pollinators of commercial crops as their population per colony is far larger than any other pollinator species. Although introduced bumble bees, native solitary bees, flies, wasps and other insects contribute to pollination, they cannot be relied upon as they have insufficient numbers or they are not always present. Without honey bees most of our horticultural and cropping industries would no longer be economically viable. The persistence of clover in pasture, especially with the additional pressure of clover root weevil may also be compromised. The introduction of varroa (the parasitic bee mite) into New Zealand means that honey bees can no longer survive without human intervention in areas where varroa is present. Pollination services provided by the feral honey bee population, hobby beekeepers and commercial beekeepers are no longer guaranteed. Because of varroa, only a few feral colonies still exist in the North Island. Varroa has yet to be found in the South Island but judging from how quickly it has spread across the world this will happen in the near future. Although there is a pest management strategy designed to eradicate varroa from the South Island when it arrives this is likely to only delay its eventual establishment. The numbers of hives required for pollination depends on a number of factors. These factors include, but are not limited to: o the attractiveness of the flower to bees o the need for cross pollination for fruit or seed development o the economic conditions for the crop o the presence of managing or feral colonies in the surrounding environs. This briefing paper summarises future trends in pollination hive requirements and pollination hive availability. The trends are based on a survey of beekeepers and primary industry projections. In order to gauge the level of demand for pollination hives over the next 10 years, the industry representatives were asked to confirm the area of crop in production now, confirm the typical number of hives introduced to pollinate the crop and what time of year, plus estimate any planned changes in planted area. At present some of the surveyed industries such as citrus and strawberry do not typically introduce hives for pollination. With the reduction of feral bee populations resulting from varroa, it is not known whether the level of pollination of these crops will remain sufficient without the purposeful introduction of hives. If the introduction of managed hives for pollination proves necessary for these crops in the future, the following estimates of pollination hive demand will be even higher. A summary of other external factors which may impact on honey bee availability is also provided (e.g. arrival of new pests or sub species of bees). The aim of this briefing paper is to provide information that can be used to form the basis of a 2

5 strategy to ensure that pollination of crops, which is essential to the continued wellbeing of New Zealand s primary industry economy, is not compromised, To determine the number of colonies available and the number of colonies required, two surveys were conducted. The first involved commercial beekeepers and the second survey involved people representing a range of horticultural and arable crops that rely on honey bee pollination. A total of 155 (54%) beekeepers returned completed beekeeper survey forms. These beekeepers own 202,000 colonies which represent 69% of the New Zealand hive holdings. The beekeeper survey asked questions on the size and location of the apiary, the percentage of hives the beekeeper supplied for pollination and potential changes in their pollination business (appendix 2). Thirteen representatives from the horticultural and arable cropping sector were asked to participate in the second survey. Telephone follow up resulted in a 100% survey response. To determine the split of the crops between the North and South Island published data 1 was coupled with data from industry survey respondents by telephone and . The survey to determine the demand for pollination hives concentrated on the area planted in crops requiring hives for pollination, any expected changes in that area in 2010 and 2015 and the number and timing of hives introduced for pollination. A copy of the beekeeper survey and an example of the industry survey is appended (appendix 3). 1 FreshFacts 2005, HortResearch ISBN

6 CHANGES IN PLANTED AREA Table 1 provides an estimate of the area planted in various crops currently and the best estimates of changes in area in 2010 and The estimates have been rounded to the nearest 5 ha. Table 1 Estimate of area planted in various crops currently, in 2010 and in Area Planted (ha) Crop Current 2010 (est) 2015 (est) Comment Apples 12,150 10,000 10,000 Clover (for seed) 10,000 12,000 13,200 Kiwifruit Green 8,680 10,000 10,000 Squash 8,440 8,440 8,440 Brassicas (for seed and oil) 5,000 6,000 6,000 Avocado 4,310 6,170 7,400 Kiwifruit Gold 1,750 2,000 2,500 PVR runs out in 2018 Radish (for seed) 1,500 1,725 1,725 Blackcurrants 1,310 1,380 1,400 Pears 910 1,500 2,000 Peaches More plantings may occur if the fortunes of the pipfruit industry do not improve. Carrots (for seed) Apricots Cherries Nectarines More plantings may occur if the fortunes of the pipfruit industry do not improve Kiwifruit Green Organic Blueberries Plums Raspberries Boysenberries Blackberries Kiwifruit Arguta It is estimated by industry participants that the area in most crops is going to increase. The significant increases are in the area planted in avocados, brassicas, clover for seed green and gold kiwifruit and pears. It is estimated that the area planted in apples will decline. Hives used in pollination Table 2 provides detail on the number of hives that are introduced per hectare for particular crops. The table attempts to merge best practice with typical industry practice. Where significant differences between the two exist, comment is provided. 4

7 Table 2 Crop Number and timing of pollination hives introduced per hectare. Month Bees In Month Bees Out Hive Requirements (hives per hectare) Comment Apples Sept Oct 4 It is estimated that only 25% of growers introduce hives. This will increase due to issues with poor pollination in the 2005 spring thought to be related to low bee numbers. Apricots Aug Sept 8 Avocado Sept Nov 10 Though the recommendation is for 10 hives per hectare it is unlikely that more than 5 hives per hectare are introduced Berry fruit o Blackberries Oct Oct 6 o Blackcurrants Oct Nov 5 o Blueberries Aug Oct 1 o Boysenberries Oct Oct 6 Brassicas (for oil Oct Jan 3 and seed) Carrots Dec Jan 5 Clover Dec Jan 3 Kiwifruit Arguta Oct Oct 10 Kiwifruit Gold Oct Oct 6 Kiwifruit Green Nov Dec 8 Kiwifruit Green Nov Dec 8 Organic Pears Sept Oct 6 Radish Nov Mar 3 Raspberries Nov Nov 6 Squash Dec Feb 2 Summerfruit o Cherries Sept Oct 10 o Nectarines Aug Oct 5 o Peaches Aug Oct 5 o Plums Aug Oct 8 The peak demand for hives occurs in November when many crops are flowering. It is estimated that a maximum of 88,675 hives are currently required to pollinate crops in November (Fig. 1). If growers were to use the full complement of hives recommended, this peak demand could lift to 117,675 hives. To assist in presentation, some of the smaller crops with less demand for hives have been amalgamated into an other category and summerfruit crops have been amalgamated (Fig. 1). 5

8 Estimated Hive Demand Figure 1. August September October November December January February March Month Kiwifruit Green Avocado Apples Kiwfruit Gold Blackcurrants Brassicas Pears Kiwifruit Green Organic Summerfruit Clover Squash Other Estimate of Current Demand for Pollination Hives by Month. With the increase in area expected to be planted (predominantly green kiwifruit and avocados) and the anticipated increased use for hives in apple pollination, the peak demand increases to 108,150 hives by November 2010 and 118,675 hives by If growers were to introduce the recommended levels of hives into their orchards these figures would increase to 133,575 and 142,175 respectively (Fig. 2 and 3). Figure Projected demand for pollination hives by month. 6

9 Figure Projected demand for pollination hives by month. Demand for hives between the North and the South Island Given the peak month for hive demand is November, it is worthwhile to consider where these hives are required. Currently, the movement of bees from the North Island to the South Islands is restricted in an attempt to extend the time period before varroa infests South Island apiaries. This movement control means that any hives that are moved from the South Island to the North Island to avert any temporary shortage of hives in the North Island cannot be returned to the South Island. An analysis of the demand for hives shows that of the 88,675 hives currently required in November for pollination, a significant proportion of these are required in the North Island. Of the key crops 2 requiring hives during this month, 78% (66,600) of them are required in the North Island. This is projected to increase to nearly 80% (80,600 hives) in 2010 and 2015 (87,500 hives). In Figure 4, further detail is provided on the current and projected hive demand in the two main islands in the month of November. 2 Analysis of the locational requirements of some of the crops requiring fewer hives was not done. 7

10 Figure 4. Current and projected hive demand for key crops in the North and South island for November. If growers were to introduce hives at the rate recommended, these peak levels for hives in the North Island in November would increase significantly from 85,100 currently, to 96,875 in 2010 and 102,500 in 2015 (Figure 5). Estimated Hive Demand 120, ,000 80,000 60,000 40,000 20,000 - North Is South Is North Is South Is North Is South Is Blackcurrants Pears Kiwifruit Green Organic Apples Brassicas Kiwifruit Gold Avocado Kiwifruit Green November Currently November 2010 November 2015 Time Period and Island Figure 5. Current and projected hive requirements for key crops in the North and South Island for November, if hives are introduced at recommended rates. 8

11 In the South Island, a peak demand of 28,460 hives are required for current pollination. The peak occurs in December with the major crops being brassicas, carrots and clover. Currently there are only 128,519 hives in the South Island. The South Island beekeepers that were surveyed represented 85,350 (66%) hives. They considered that only 51% (65,545) of hives would be strong enough for pollination. The survey indicates that only 47,000 hives are used for pollination. However, there is an anomaly with the surveys because there are an additional 14,000 hives in Canterbury that are owned by beekeepers who have catergorised these hives as honey collectors and not pollination hives. These same 14,000 colonies are considered by the owners of clover seed crops to be conducting pollination. These 14,000 colonies are therefore included in the following calculation. If 51% of the colonies from the beekeepers that responded are suitable for pollination this totals 31,110 hives. If this is projected for the South Island then 41,687 hives would currently be suitable to conduct pollination. Hence the current supply of hives is sufficient. In 2015 the number of hives required for pollination increases to 35,800. The predicted number of hives available for pollination in 2015 is 41,376. This is sufficient to conduct pollination. However, it is unknown what impact varroa will have on hive numbers. When varroa is found in the South Island, the number of hives may decrease by 24% as they did in the North Island. If this occurs and it is coupled with a decrease in honey price there would be a shortfall of 72,950 hives by In appendix 4 the impact of four likely scenarios have been estimated. The effect of reduced hive numbers on the pollination of clover present in pasture is not clear. This is mainly because the level of seed set required to maintain clover in pasture is unknown. Availability of additional hives Eighty-five percent of the beekeepers surveyed in the North Island carried out pollination using an average of 69% of their hives. In the South Island 48% of the beekeepers surveyed carried out pollination using an average of 53% of their hives. The percentage of hives used for pollination appears to depend on proximity to crops requiring pollination. For example, in the North Island the 18 beekeepers that supplied 90% of their hives for pollination had their hives situated in the Waikato or Bay of Plenty, close to kiwifruit and avocado crops. Of the 19 beekeepers supplying less than 60% of their hives for pollination only two were from the Waikato or Bay of Plenty. The income from hive rental was the most common reason given for being interested in supplying more hives for pollination. If areas were short of hives it is probable that beekeepers would move hives from large distances if the rental prices were attractive enough. However, it should be noted that not having to move hives large distances was also a significant factor in not supplying hives. 9

12 The relationship between hive price and willingness of beekeepers to provide hives for pollination is unclear. The increase in the price of hives used for kiwifruit pollination ($100 $160/hive) did not result in an increase in the number of beekeepers carrying out pollination. Beekeepers did not indicate that they would be more inclined to carry out pollination if honey prices were significantly lower. If honey collection became uneconomic beekeepers indicated that they would no longer keep bees rather than change their income stream to conduct more pollination. In many cases this was due to the large distances involved in moving hives and the negative aspects of carrying out pollination including working at night and heavy lifting. The lack of an obvious connection between willingness to carry out pollination and the economics of providing hives is unexpected and should be treated with caution. Trends in beekeeper numbers and hive numbers in the North and South Island The data on managed hive numbers in New Zealand come from information collected under the Apiaries Act before 2000 and since then under the Biosecurity Act. Every year all beekeepers are required to report the number of hives and apiaries that they own. Although most hives are recorded some were not, especially pre 2000 when a levy on hive numbers was charged. Beekeeper numbers Since 1990 there has been a gradual decrease in beekeeper numbers in New Zealand (Fig. Beekeepers Year South Island North Island Figure 6. The number of beekeepers in the North and South Islands since ). The decrease has accelerated in the North Island since the arrival of varroa. This is predominantly due to the reduction in number of hobby beekeepers. Beekeepers owning less than 50 hives make up approximately 95% of the total number of beekeepers but only own approximately 10% of the hives. The reasons for the decline, prior to the arrival of varroa, are unclear. It is possibly due to beekeeping becoming less attractive as a hobby with the trend toward metropolitan lifestyle. The reduction since varroa is probably the result of many hobby beekeepers not having the skills or interest in treating varroa and hence their hives dying. Whilst the loss of beekeepers has probably had little effect on total hive numbers it has reduced the potential number of skilled beekeepers who could have assisted in maintaining hive numbers. Most of the 13,000 hives (approx.) owned by hobby beekeepers are situated in city areas and not usually used for paid pollination. 10

13 Of the beekeepers surveyed that currently provide, or intend to provide pollination hives, North Island beekeepers could only commit 71% of their hives for pollination on average and South Island beekeepers only 51%. The difference is probably due to the colder spring conditions usually experienced in the South Island. This means that there would only be 98,281 colonies available in the North Island and 41,376 in the South Island. Honey bee hive numbers New Zealand s honey bee population is made up of both managed and feral colonies. Because the location of all managed colonies must be reported to the Management Agency (National Beekepers Association) for the American foulbrood pest management strategy, the approximate number of colonies present in New Zealand is known. The number of feral colonies however, is unknown. Perhaps the largest decline in beehives due to varroa has been in built up areas. This has been exacerbated by some councils placing increasingly difficult restrictions on beekeeping in cities. The net result has been many reports from home gardeners on lack of pollination of vegetables and fruit trees. Although not a major economic issue it is a quality of life issue for some people. The importance of this has not been assessed. Managed colonies The number of managed colonies in New Zealand reached 340,000 colonies in 1990 but had declined to 320,000 in 2000 (Fig. 7). A low of 293,000 colonies was recorded in Between 1995 and 2000 there was an increase in hive numbers most likely associated with an increase in the price of honey. Since 2000 there has been a steady decline in hive numbers, presumably because of varroa. This can be seen by reviewing the spread of varroa in the North Island (Figure 8) and the number of colonies in the upper and lower North Islands (Figure 9) Hive number (X 1000) Year Figure 7. Number of colonies present in New Zealand. 11

14 Figure 8. Spread of varroa in the North Island. 105 Percent of hives present in Upper North Island Lower North Island Year Figure 9. Percentage of hives in the lower and upper North Island present in When varroa was found in April 2000 a line was drawn across the centre of the North Island (Fig. 8) beyond which hives or beekeeping equipment that might carry varroa were not permitted to move south. The purpose of the line was to slow rather than stop the southward spread of varroa, largely by restricting the movements of migratory beekeepers. This line was removed in September 2003, as approximately 100 apiaries south of the line were known to be infested, meaning that it was no longer cost effective to maintain this arbitrary boundary. With almost all of the 10,000-plus apiaries north of the line infested, having the line in place probably 12

15 delayed the spread of varroa into the lower North Island by about two years. Varroa can now be found in almost every hive in the North Island. Since 2000 the number of colonies in the lower North Island has slightly increased. Conversely, the number of managed colonies in the upper North Island decreased by 16% (21,601) in 2004 and 13% (17,789) in The losses would have been larger if more than 10,000 hives had not been moved from the South Island to the upper North Island. Feral colonies Feral colonies usually live in hollow trees, man made structures such as buildings and bridges, and occasionally in caves. They are usually hard to locate and almost impossible to count. The only estimate comes from information collected in the Hamilton city area. During a public appeal, 104 feral colonies were identified. Many of these were in public areas and none were reported twice suggesting the actual number was much higher. In another location seven feral colonies were recorded inhabiting the supports for a bridge. The number of feral colonies (pre varroa) is probably related to the number of available nesting sites and food availability. There were possibly, pre varroa between 10,000 and 50,000 feral colonies in each island. Although not specifically studied in New Zealand varroa has probably reduced the number of feral colonies by about 99%. Instead of feral colonies surviving for many years, many are now annual. A swarm leaving a managed colony and establishing a new colony in a suitable nesting site takes varroa with them. Varroa will then multiply and kill this feral colony in about one year. ADDITIONAL THREATS TO HIVE SUPPLIES There are four major issues that will impact the supply of hives for pollination. These include varroa, toxic honey, plant alkaloids and the introduction of exotic honey bee pests and diseases. Although hive supplies can be increased rapidly, through the splitting of hives in spring, the build up of these new hives can be too slow for their use in pollination later in the season (November). 1) Future effects of varroa Further varroa spread It is expected that the hive numbers in the lower North Island will also decrease over the next few years as the effects of varroa are fully felt. The pest management strategy to keep varroa out of the South Island is likely to only delay the introduction of varroa after which time varroa is likely to reduce colony numbers there as well. Resistance Resistance of varroa to control products is a problem worldwide. The pesticides we have available are not sustainable long-term. There can be as many as 20 generations of varroa each year and because varroa reproduce sexually they can quickly build up resistance to chemical control products. In the USA varroa populations that cannot be killed by any of the varroa control chemicals are present. This is part of the reason the USA lost between 40-60% of their hives last winter and they had to start 13

16 importing bees from Australia to pollinate their almond crop (Appendix 1). We expect to start having hive losses due to resistance within the next five years. Economics Economics is a major problem for varroa control. Varroa has increased the costs of keeping bees by between $30 - $50 per hive when pesticides, labour and hive losses are included. Fortunately, at the same time as varroa was found in New Zealand, international honey prices doubled (Fig. 10). This was coincidence rather than cause an effect. China which is an important honey exporting country was caught using an illegal antibiotic to control bee diseases. Residues of the antibiotic were detected in a number of their markets and Chinese honey was banned. This caused a dislocation Price ($) per kg in the world honey market which in turn increased honey prices. The price increase enabled beekeepers to absorb the increased varroa costs. Coupled with the increase in honey price was the high honey production experienced over the seasons (Fig. 11). This produced gross returns for honey per hive not seen previously (Fig. 12) Year Figure 10. Price per kg for clover honey since Production per hive (kg) Gross income per hive ($) Year Year Figure 11. Honey production per hive. Figure 12. Gross return for honey per hive (based on clover prices). The world honey prices are however falling again. Prices in Australia and Canada are now less than $2.00/kg which is similar to the price paid in New Zealand pre varroa. New Zealand s domestic market which absorbs more than half of New Zealand s honey production has been protected from imports for more than 50 years because of the risk of introducing diseases. MAF is however currently in the process of opening 14

17 New Zealand to honey imports. It is expected that honey imports will occur before July The low international prices coupled with increased competition in the domestic markets are likely to depress honey prices. Should prices return to pre varroa levels this is likely to have a major impact on hive numbers. With the increased cost associated with managing varroa many beekeepers who rely on honey would no longer find beekeeping economic. This is likely to have a larger effect on hive numbers than the effects due to varroa itself. Seventy-seven beekeepers in the North Island answered the question concerning what a reduction in honey prices to $2/kg would do to the number of hives they managed. Forty-seven beekeepers (61%) did not consider the price of honey would affect the number of hives they managed. Six percent would increase their hive numbers and 29% would decrease hive numbers. Eighteen percent did not think they would continue to keep bees. This would result in a net reduction of 31,900 hives in the surveyed North Island beekeepers which equates to a reduction of 44,000 hives (26%) from all the managed hives in the North Island. Seventy-five beekeepers in the South Island replied to the survey on the influence of honey prices. Fifty beekeepers (66%) did not think honey prices would affect their hive numbers, 9% thought they would increase hive numbers and 21% thought hive numbers would decrease. The net prediction was a decrease in hive numbers of 24% (20,000) in the south island. The similarity in hive declines in both islands was surprising considering only beekeepers in the North Island have significant varroa costs. This may reflect the higher value of Manuka honey produced in the North Island and the higher levels of pollination. 2) Toxic Honey Toxic honey is produced by bees feeding on the honey dew that immature stages of the vine hopper, Scolypopa australis (Fig. 13), produce when they feed on Tutu (Genus Coriaria) (Fig. 14). The honey is not toxic to bees but can be very poisonous to humans. The symptoms of honey poisoning include vomiting, delirium, giddiness, increased excitability, stupor, coma, violent convulsions, memory loss and on occasion death. Some of the symptoms can persist for more than a week. Relapses have been reported for up to six months after a poisoning. A single half a teaspoon of toxic honey in a cup of tea has on occasion been enough to cause unconsciousness. Before 1950, there were 213 notified poisoning cases with six deaths. One of the cases included the poisoning of 147 children from a boarding Figure 13. Scolypopa australis. 15

18 school in England, 1923, who consumed the honey at breakfast. Ten of these were seized with convulsions and 20 vomited. The honey was traced back to Te Teko in the North Island. There have been 81 reported cases in the last 50 years, the most recent being in Opotiki in It needs to be noted that there are possibly many more cases that are unreported or misdiagnosed, especially when poisoning has resulted from low concentrations of toxins. From the medical accounts of the poisonings it is surprising that a greater number of fatalities have not been reported. All documented deaths have been reported as the result of eating comb honey, rather than extracted honey. This is possibly because the extracted honey is likely to be diluted by uncontaminated honey. However, toxins in extracted honey is still a problem and have resulted in nearly 70% of the poisonings. In 1948 the Government restricted beekeeping in Figure 14. Sketch of a Tutu the Eastern Bay of Plenty following 27 poisonings (Genus Coriaria). in Pongakawa. In 1974, MAF closed the Coromandel area to beekeeping following an additional 13 poisonings and ordered all beekeepers to move their hives out between 14 December and 1 May the following year. In 1977 the restrictions were changed so hives no longer had to be moved but that all surplus honey had to be removed by 31 December. The restrictions were very effective at managing the problem. In the 30 years prior to the restrictions there were 63 poisonings and this has reduced to 16 since the restrictions were put in place. Four years ago with the change to the Animal Products Act, the Coromandel restrictions were removed. Commercial beekeepers are now required to sign a declaration that indicates whether there is any likelihood that the honey being produced has toxins. MAF has not provided any details on how beekeepers are supposed to carry out this assessment. There are also no requirements for hobby beekeepers to sign such a declaration if they are not selling to an extractor or packer. The opinion of the New Zealand Food Safety Authority regarding this situation is that further poisoning will occur and that: a media scare story will result there ll be a loss of public confidence in honey sales and price will crash Should this occur it is likely to have a detrimental effect on beekeeping economics and hive numbers. 16

19 3) Plant alkaloids A variety of plants produce alkaloids that can be secreted in nectar and found in honey. Of particular concern is Viper s bugloss (Echium vulgare) (Fig. 15). This is becoming an issue, especially in the South Island where Viper s bugloss nectar contaminates a large amount of honey produced. Should restrictions be placed on the production of Viper s bugloss honey and health warnings issued (as they have been for a similar plant that grows in Australia) this is likely to have a negative impact on the economics of beekeeping in the South Island. Figure 15. A honey bee visiting a Viper s bugloss flower. 4) Exotic pests and diseases of honey bees There are a number of honey bee pests and diseases that could further compromise the ability of the beekeeping industry to provide sufficient hives for pollination. The most significant of these are described below. European foulbrood European foulbrood is a disease of honey larvae caused by the bacterium Melissococcus plutonius (Fig. 16). Honey bee colonies are usually more seriously affected during the spring and early summer. European foulbrood is found on all continents, including Australia, although it has not been reported from Western Australia. European foulbrood has not been reported from New Zealand. 17

20 Honey bee colonies may be destroyed or seriously crippled by European foulbrood. Hence it could be a major problem for hives used for pollination. Figure 16. Honey bee brood infected with European foulbrood. Beekeepers in Australia and elsewhere find it necessary to feed antibiotics to control European foulbrood, and this would probably also be necessary if the disease were introduced to New Zealand. The feeding of antibiotics to honey bees has implications for the American Foulbrood National Pest Management Strategy, which relies on beekeepers being able to diagnose clinical signs of American foulbrood. Feeding antibiotics has been reported to suppress American foulbrood disease signs, thus making it more difficult to detect and control. Although the presence of European foulbrood would probably not result in restrictions being placed on the export of bees and bee products from New Zealand, the feeding of antibiotics to honey bees would have a negative effect on honey exports, as it is likely that some importing countries would require New Zealand honey to be tested to ensure it does not contain antibiotic residues. Therefore, the introduction of European foulbrood is likely to cause significant negative effects on hives used for commercial pollination, increased costs to beekeepers through the need to feed antibiotics to their honey bee colonies, and increased costs to honey exporters. The presence of European foulbrood in New Zealand is likely to reduce the number of hives available for pollination. Small hive beetle The small hive beetle (Aethina tumida) is a pest of honey bee combs (Fig. 17). It was first described in South Africa, and it is now widespread in the USA, Egypt and Australia. The spread of A. tumida in temperate climates of North America after its initial introduction to Florida in the spring of 1998 suggests that is would have no problems establishing in New Zealand if it were introduced. However, the extent to which the NZ climate would suit the beetle is unclear. Most affected counties in the US were those with climates similar to the subtopical and warm temperate zone of South Africa, while in colder northern areas of the US the beetle is considered unable to survive outside the hive or reproduce, over winter. Figure 17. Small hive beetle larvae damaging honey bee comb. Notwithstanding the considerably colder climate in New Zealand, it is considered that significant colony losses in New Zealand are possible, and beekeepers might need to use pesticides to control the beetles. It is likely that there would be considerable regional variation in the impact of small hive beetle in New Zealand, depending on temperature and soil type. Because of the limited distribution of the small hive beetle throughout the world, their presence in New Zealand is likely to result in restrictions 18

21 being imposed on exports of queens and package bees, further eroding the profitability of beekeeping in New Zealand. Tracheal mite Acarapis woodi is a parasitic mite that causes acarapisosis, a disease of the respiratory system of adult honey bees (Fig. 18). It has been reported as being present in most areas of the world. The only significant beekeeping countries where it has not been reported are Australia and New Zealand It is likely that honey bees in this country would be as susceptible to tracheal mites as honey bees in north-eastern United States, where, following their introduction in 1984, tracheal mites caused the death of over 30% of colonies in the winter of Therefore, severe consequences could be expected for the New Zealand beekeeping and pollination industries if tracheal mite were introduced. In addition to hive losses, the need to use chemicals to control the mite would pose additional production costs both in terms of treatment and the labour involved in administering it. Figure 18. Tracheal mites in Tropilaelaps the trachea of a bee. Tropilaelaps clareae is a parasitic mite associated with honey bees. If left unchecked, the mite population can rapidly cause the death of the colony. It has been found in southeast Asia, Afghanistan, China and Kenya. The establishment of T. clareae would likely cause severe consequences for the New Zealand beekeeping and horticultural industries. T. clareae is considered to be a more serious pest than varroa in southeast Asian countries where both mites exist. The presence of T. clareae could have a major effect on the export of queens and package bees from New Zealand, even though the short survival period of the mite on adult bees probably means that live package bee exports are unlikely to transport T. clareae. Africanised bees Apis mellifera scutellata is a subspecies of honey bee naturally occurring across eastern and southern Africa from Ethiopia to the Cape. Africanised bees have a number of behavioural traits that make them difficult to manage, the most important being their exceptionally high level of defensive behaviour. Since its introduction to Brazil, the subspecies has spread into much of South America, all of Central America, Mexico, and into some areas of the southwestern United States. 19

22 Should Africanised bees become established in New Zealand, the consequences on beekeeping are likely to be severe. It is likely that the export of queens and package bees would stop, or at least be seriously affected. The behaviour of Africanised bees would also affect beekeeping practices. Many Latin American countries now require bees to be kept m from roads, agricultural fields and dwellings. A similar requirement in New Zealand would mean that much of the country would become unavailable to beekeepers. Major difficulties would also occur if a high percentage of the colonies used for kiwifruit pollination were to become Africanised. Restrictions could prohibit the use of Africanised honey bees for pollination in such situations. It is highly likely that the keeping of bees in built-up areas would be prohibited. European strains of honey bee existing as feral colonies in New Zealand would be displaced by Africanised colonies as a result of preferential mating behavior, a shorter development time for Africanised queen bees and the increased production of Africanised swarms. The behaviour of Africanised bees would also pose a significant potential public health problem, with increased stinging incidents and increased public resources devoted to swarm and feral colony destruction. Should Africanised bees become established in New Zealand the ability of the beekeeping industry to provide sufficient hives for pollination will be seriously compromised. Cape Honey Bee The Cape honey bee (Apis mellifera capensis) is a subspecies of A. mellifera found in the Cape region of southern Africa. When colonies of other subspecies of honey bee are kept within flight range of A. m. capensis, laying workers of the Cape bee are likely to enter the colonies. The laying workers mimic a series of queen pheromones and are able to successfully escape reproductive suppression from the resident queen and adult bees. The social parasitism and usurpation displayed by A. m. capensis suggests that even at low frequencies in the wild honey bee population, the subspecies could cause an on-going threat to beekeeping activities with other sub-species of honey bee. Beekeepers requeening to make up losses might not be able to overcome those losses. Losses could also impact on the price and availability of hives used for commercial pollination activities. Establishment of the sub-species would also likely stop (or at least seriously affect) the export of queens and package bees from New Zealand. CONCLUSIONS An analysis of the demand for hives shows that of the 88,675 hives demanded currently in November for pollination, a significant proportion of these are required in the North Island. An analysis of the key crops 3 requiring hives during this month shows that 78% (66,600) of them are required in the North Island currently. This is projected to increase to nearly 80% (80,600 hives) in 2010 and 2015 (87,500 hives). 3 Analysis of the locational requirements of some of the crops requiring fewer hives was not done. 20

23 With the increase in area expected to be planted (predominantly green kiwifruit and avocados) the peak demand could increase to 103,150 hives by November 2010 and 108,675 hives by If growers were to introduce the recommended levels of hives into their orchards these figures are projected to increase to 133,575 and 142,175 hives respectively. Of the beekeepers surveyed that currently provide, or intend to provide pollination hives, North Island beekeepers could only commit 71% of their hives for pollination on average and South Island beekeepers only 51%. The difference is probably due to the colder spring conditions usually experienced in the South Island. This means that in 2015 there would only be 98,281 colonies available in the North Island and 41,376 colonies in the South Island (appendix 4). The number of hives currently available are sufficient to supply existing requirements but are not predicted to be sufficient by If the predicted reductions in hive number due to varroa and reduced honey prices eventuate, this situation will be more critical. It is estimated there is likely to be a shortfall of 72,950 hives nationally by Appendix 4 provides detail on some of the possible scenarios. According to the survey of beekeepers undertaken in New Zealand, and current experience from America increasing hive rentals will not eliminate the shortfall in hive supplies. 21

24 APPENDIX 1 US: Honeybee shortage sours fruit, nut harvest By Linda A. Johnson, Associated Press TRENTON, N.J. - With all the sophisticated technology today's farmers use, little honeybees remain crucial, pollinating billions of dollars of fruit, vegetable and nut crops each year while collecting food for their hives. But the number of honeybees and managed beehives is down so much that production of pollinated plants has fallen by about a third in the last two years from the usual $15 billion per year. "I've heard people complaining about bee shortages all over the country," said Kevin Hackett, head of the U.S. Department of Agriculture's research program for bees and pollination. He said 15 years ago, "there were twice as many hives as there are now." Today, commercial beekeepers manage 2.5 million U.S. colonies, or artificial wood-andscreen box hives, with roughly 65,000 bees each. The big drop in the honeybee population the last several years is mostly due to the parasitic varroa mite destroying more than half of some beekeepers' hives and wiping out most wild honeybees. Commercial beekeepers, crunched by huge bee losses and rising costs for fuel and chemicals to kill varroa mites, have boosted the fees they charge farmers to rent honeybees. Given the varroa mite epidemic, other environmental pressures and a drop in the number of beekeepers, government agencies and even the National Honey Board are pouring money into research to help the honeybees bounce back and grant programs to get more people into beekeeping. The National Academy of Sciences has even appointed a group to investigate whether all bees, butterflies, birds and other pollinators in North America are endangered by habitat loss, insecticide use, invasive species and other influences. For farmers dependent on pollination, the current shortage means they must pay higher bee fees that they generally can't recoup or risk a big drop in crop production. "I think some of the growers are going to rent less hives this year and take a chance" yield holds up, said Ned Lipman, who raises cranberries on two 50-acre farms in Manchester and Berkeley townships, in New Jersey's Ocean County. "There's an acute shortage of bees nationwide," Lipman said. Honeybees and some wild insects and birds, in extracting nectar and pollen from the flowers of crops and transferring pollen grains among plants, increase the size and total yield of crops from apples to zucchini. Until World War II, most U.S. farmers maintained their own honeybee hives; early settlers brought beehives from Europe along with crop seeds. Now Lipman hears he'll have to pay $55 for each of the 200 honeybee hives he normally rents each spring, up from $42 last year. The bee shortage is hitting California farmers particularly hard, because the fast-growing popularity of almonds grown there has sharply increased demand for honeybees when the supply is much lower. Almond pollination prices have risen dramatically, from less than $50 per colony to as much as $150 per colony in just three years, said Daniel Weaver, president of the American Beekeeping Federation and a fourth-generation beekeeper with more than 8,000 honeybee colonies in Texas, North Dakota, Montana and California. The higher prices beekeepers can command in California, in turn, has led some to shift beehives there from states farther east, despite the cost and time involved in getting approval to ship bees across some state lines. Lipman said that's exacerbated the beehive shortage elsewhere. 22

25 Besides the harm to hives from nature's effects, interest in beekeeping has been falling as commercial beekeepers and hobbyists alike get older and give it up. That's one reason New Jersey's Department of Agriculture started a new program giving $300 grants to first-time beekeepers to cover costs of starting up a hive - after completing the "Bee-ginning Beekeepers" training course offered each spring by Rutgers University's agricultural school, Cook College. The grant program aims "to get more people interested in keeping bees, in hopes of some people getting into it commercially," said Bob Hughes, president of the New Jersey Beekeepers Association. Hughes, 72, tends more than 200 hives set up on a couple dozen farms and in gardens on large properties around the state. Some of his hives are used for the field training on the final day of the beekeepers course, when students learn how to safely handle bees, remove honey and maintain the hives 23