The Department of Conservation oversees approximately 8-million hectares of New Zealand’s land, much of it valuable for the purpose of beekeeping. What’s their attitude towards the honeybee and what has shaped it? And, how does their thinking fit within the global context? Science writer Dave Black looks into the evidence, and finds the answers to those questions are shaped by ‘ethics’ just as much as any science.
By Dave Black
For all sorts of reasons New Zealand has an attitude problem when it comes to ‘non-native’ species, including introduced bees. They represent an uneasy colonial history, can compete with or displace other existing species we like, and might introduce novel diseases and challenges that damage our economic productivity. Immediately the irony of the situation must be obvious. This is a country that owes its existence and prosperity to the movement of species, human, bovine, and ovine, to point out a few. This creates an extra set of problems if you administer the contentious assets that represent the nation’s natural and cultural heritage, the bit we grandly call our ‘conservation estate’.
New Zealand Conservation
It wasn’t until the 1960s that the tension between the economic value to resource development and the ecological value of the remaining undeveloped land finally surfaced. The Maruia River Declaration, a public petition in 1975, demanded a stop to the logging of native forest and ultimately led to the formation of the Nature Conservancy. In 1987 the Conservation Act formed the Department of Conservation (DOC) and established three land agencies with separate but conflicted responsibilities (DOC, Landcare, and the rapidly defunct NZ Forestry Corporation) after a lengthy period of government prevarication[1].
The Act defined conservation imprecisely and merely read; “Conservation means the preservation and protection of natural and historic resources for the purpose of maintaining their intrinsic values, providing for their appreciation and recreational enjoyment by the public, and safeguarding the options of future generations.”[2]In New Zealand, the purpose of conservation remained as action to preserve the status quo; conservation means preservation. More than that, it was mainly about preserving the past, our ‘heritage’, albeit with a nod to our future ‘options’. Any activity on DOC land now required a permit, a ‘concession’, unless it had been specifically excluded from the requirement in law[3].
What DOC has to Manage
Beekeepers were not the only ones to respond to the demand for mānuka honey and its high economic value. DOC too found itself with statutory obligations to both facilitate and adjudicate new activities in the land it was responsible for and now one was beekeeping. On one hand it had a role to play in furthering the country’s prosperity and business growth agenda, while potentially taking the opportunity to lessen its cost to the taxpayer by exploiting some arguably underutilised assets. Besides the value of the honey (mānuka is not the only plant; nectar not the only resource), the land could also provide a critical ecosystem service supporting the health of an agricultural pollinator used elsewhere. There was also a duty to tangata whenua, both as ‘trustees’ of land temporarily affected by the tiriti (Treaty of Waitangi) reconciliation process, and because it is charged with maintaining somewhat inseparable cultural values; whenua, taonga, and social cohesion generally, for which local employment and trade matter.
On the other hand were a series of occasionally quite novel issues challenging for their conservation role. There was the problem of mānuka hybridisation if several varieties were present in an area for example. Issues arise like degrading a local taonga, or interfering with the plant’s natural distribution – with its function as one instance in a natural ecological succession, or from varieties that support conflicting uses, such as oil, or honey or rongoā Māori. If the plants are selected or planted for some commercial purpose, how are the liabilities and benefits distributed? And, more opaquely, what intellectual property rights exist that must be managed? What’s a fair way of assigning uses to competing commercial businesses, and how could you enact borders between users (such as beekeepers) anyway?
Siting honeybee colonies on conservation land had obvious, but not necessarily better understood, issues. There are access routes (and public nuisance), stocking rates, foraging distances, effects on local pollinator networks (pollinators and the pollinated, both for native and exotic species), and the movement of pathogens (concern about PSA became Myrtle rust worry[4],[5]).
The ‘Precautionary Principle’
To try and understand the possible issues from honeybees DOC commissioned a risk analysis that was published in 2015[6], authored by Catherine Beard. The problem for a risk analysis is that there were few studies about the problem anywhere in the world, and even fewer relevant in New Zealand conservation areas[7]. That is still true; hardly anyone studies invertebrates. The quality of the studies available leaves a lot to be desired. Mostly observational, these provide equivocal results, seldom provide experimental measurements of effect on species ‘fitness’ (like growth and reproduction) and fail to deal with the details of resource use in complex, dynamic ecosystems over time. The evidential deficiency means we can’t make ‘possible’ mean ‘probable’.
Even when a study reports an effect we don’t always know what it means. For example, honeybees displacing bumblebees at flowers (and vice-versa) may not be advantageous to either pollinator, but it was an advantage for the flower, improving cross pollination rates[8]. We cannot assume competition between pollinators is ‘a bad thing’[9].
One of the scientific studies referenced by the DOC analysis concluded like this:
“This review shows that there are potentially many and varied effects of honey bees on native flora and fauna. Some suggestions of negative effects by honey bees are reasonable, but they are seldom supported by incontrovertible evidence. Those concerned about the conservation of native species should place effects by honey bees in context. Thus far, the effects of introduced honey bees appear to be relatively subtle, especially in comparison to other introductions and habitat loss. No evidence exists to indicate drastic effects by honey bees on native systems, or radical alteration of native communities. Until data are available, characterization of the honey bee as a serious conservation threat is unwarranted.” [10]
Regardless of their limitations it’s fair to say most expert review papers[11] on the topic conclude that when honeybees are introduced to environment beyond their ‘native’ range some negative effects on indigenous ecologies are possible, and DOC’s assessment was no exception. Consequently, as one of the most useful reviews (to me) from Victoria Wojcik and her collaborators notes,
“Recently, some beekeepers have seen access to public and private natural lands questioned, limited, or rejected because of concern that wild bees are being put under undue stress due to competition with managed honey bees for food. Decisions made in these cases have largely been based on opinion rather than on scientific evidence or have made use of published resources that suggest precautionary approaches to managing honey bees and conserving wild bees that are not based on direct experimental evidence. Management decisions have also focussed strongly on the origins of honey bees, as it is the mandate of some public and private organizations to support native species, and thus not to promote non-native species.”[12]
While acknowledging the uncertainty[13] land managers feel they have to reach a decision and can’t pay for endless scientific projects. The 2015 DOC analysis concludes “Despite the lack of conclusive scientific evidence for the impact of honeybees in the natural environments of New Zealand, they do pose a very real threat to indigenous biodiversity. Therefore, it is recommended that the precautionary principle is used to inform the management of honeybees on public conservation lands in the interests of both conservation and economics.” Housing hives in conservation areas was a complex issue anyway; the uncertainly about what ecological effect they might have didn’t make it any easier. The cautious ‘better safe than sorry’ precautionary principle is an ethical position, not a scientific one, one in which the obligation to do no harm is more important than the obligation to do some good. That’s not surprising from an organisation charged with keeping things as they are.
So That’s the Policy, but is it ‘Right’?
Ecosystems always change; it’s change that is ‘natural’. Some changes are rapid, perhaps a result of natural disasters or invasive species, and occur in decades or a few millennia. Some changes take many millions of years, only observable in the aeons and eras of the palaeoecological record. It’s not easy to separate the overlying perspectives. As far as the inhabitants go, as ecosystems are in a constant state of flux sometimes distinguishing between an agent of change or an entity just taking advantage of change isn’t straightforward[14].
The first, perhaps unconscious, value judgement conservationists all around the world make is one Jonah Peretti has described as ‘nativism’[15]. ‘Non-native’ species are disparaged for driving beloved ‘native’ species to extinction and polluting ‘pristine’ natural environments, but ‘nativeness’ is not either in itself a sign of evolutionary fitness or of a species having desirable qualities. What is it that makes one species native and another not? How long is it before a resident species becomes native? When does range expansion or dispersal become invasion? Does being native have any special value?
New species do not suddenly spring into existence perfectly suited to their natal habitat and no other. They would not be displaced if they were. Ecosystems are almost always a blend of long-term residents and ‘new’ arrivals, and the idea that we can sift though and sort out who belongs and who doesn’t at an arbitrary point in time based on an incomplete natural history is kind of flawed. Nor does it look as though the mode of transport is a reasonable criterion to add. The practical result of a ‘natural’ arrival on the wind, rather than a container-ship stowaway, is the same.
If we are to retain a sense of ‘nativeness’ maybe it should be redefined. Does the interloper now possess a genetic adaption to the new range[16] and, do pre-existing inhabitants show an adaption to the exotic species, that is, recognise a loss of novelty?[17] Maybe. If we were being honest, we might admit that ‘belonging’ had more to do with their charisma and our identity than it should.
What’s ‘belonging’ Anyway?
There are more than 16,000 species of bees catalogued worldwide[18]. Of the 41 species known in New Zealand eight have been imported by man in the last 150 years, six imported themselves (five from Australia; one from Europe), while the remaining 27 have never been found anywhere else[19]. Somewhat over a third of the bee species here are ‘alien’. However, there is plenty of evidence to suggest these introduced bees are not the same as the populations they originated from[20]. A recent British attempt to reverse environmental degradation and re-introduce a bumblebee species that arrived in New Zealand between 1885 and 1906 found that the bees had diverged from the originating strain and would have to ‘re-adapt’ if they were returned ‘home’[21]. It’s exactly what any bee breeder would expect, but the non-native status of honeybees in New Zealand is not up for debate. What is contentious is whether non-native honeybees are ‘a bad thing’.
And Mānuka?
And what of the ‘native’ plant that brought the issue to everyone’s attention? The most up-to-date information we have has mānuka originating in Australia, diversifying in more than 80 species (one of them Leptospermum scoparium) that expanded their range into several areas of the southern Pacific[22],[23]. The New Zealand ‘flavour’ L. scoparium, arrived via Tasmania, or directly, between two and five million years ago as a trivial part of the native flora. Now two varieties of the species are currently recognised here, although there may be up to five geographical segregated, physically different varieties or ‘ecotypes’[24].
Just as our Apis mellifera separated from its ancestor, if you look closely enough the varieties of L. scoparium we have here differ between themselves, and from the current Australian species. These became a much more significant contributor to local vegetation after Man’s arrival 700-800 years ago cleared a good deal of the forests. It’s not clear whether mānuka’s ‘Aussie’ tolerance to fire assisted this or if much of this trait had been lost since its arrival[25], but undoubtedly mānuka’s success was coupled to human success.
Impending decisions
The former Chief Executive of UK’s Woodland Trust is one of a growing group of scientists that argue the native/non-native distinction is no longer useful and potentially a threat to biodiversity. It may actually be the view of a majority of scientists[26]. He sees ‘native’ as a social construct, merely “tokens of nationality [that] are not fixed entities, they are transitory arrangements of geopolitical serendipity”[27]. We need to see humans as part of the natural world and develop a more thoughtful and balanced view of non-native species[28], particularly as we deal with a warming planet. Writing for the online magazine Yale Environment 360,science journalist and author of 'The next Great Migration', Sonia Shah senses the change in mood and wonders if policy-makers are prepared for the transformation that climate change will bring[29].
The Precautionary Principle is not meant to be an excuse for inaction, or universally applied to every decision, a grown-up version of hiding under the bed-sheets. It’s not self-evidently appropriate. In principle, it’s a useful strategy faced with irreversible change and potentially catastrophic consequences, but it doesn’t necessarily address and resolve conflicts. Co-existing in the evolving ecosystems that sustain us all means we need to consider a much more intelligent approach to maintaining and enhancing biodiversity than building an Ark permits, even if we do need the occasional lifeboat.
No matter the vessel, DOC appears unnecessarily wary of including the honey bee.
References [1] For a detailed account of the period see Guy Salmon’s, Background and history of development of the conservation estate in New Zealand. A report for Parliamentary Commissioner for the Environment. Ecologic Foundation. 20 May 2013 [2] Conservation Act, 1987. Part 1, 2 Interpretation, (1) [3] Ibid, Part 3B from section 7(1) of the of the Conservation Amendment Act 1996 [4] Luzie M.H. Schmid, Mark F. Large, Mel Galbraith and Peter J. de Lange, Observation of western honeybee (Apis mellifera) foraging urediniospores from myrtle-rust infected maire tawake (Syzygium maire), Ōwairaka/Mt Albert, Tāmaki Makaurau/Auckland, New Zealand [5] Jorgiane B. Parish, Eileen S. Scott, Raymond Correll, Katja Hogendoorn, Survival and probability of transmission of plant pathogenic fungi through the digestive tract of honey bee workers. Apidologie (2019) 50:871–880DOI: 10.1007/s13592-019-00697-6 [6] Beard, C. (2015) Honeybees (Apis mellifera) on public conservation lands: a risk analysis. Department of Conservation, Wellington [7] For instance, see B. G. Howlett, B. J. Donovan, A review of New Zealand’s deliberately introduced bee fauna: current status and potential impacts New Zealand Entomologist Vol 33: 92-101 (February 2010); Claire Murphy and Alastair Robertson, Preliminary study of the effects of honey bees (Apis mellifera) in Tongariro National Park. Department of Conservation, 2000. ISBN 0478219393; Donovan, B.J. (1980) Interactions between native and introduced bees in New Zealand. New Zealand Journal of Ecology 3: 104116; Jay Masao Iwasaki, Phd Thesis: Interactions between bee species in relation to floral resources. University of Otago, Dunedin, New Zealand 2017; Rebecca Marie Bennik. Msc Thesis: The effects of honeybees (Apis mellifera) on the biodiversity of manuka (Leptospermum scoparum) patches. Massey University 2009. [8] G. Sapir, Z. Baras, G. Azmon, M. Goldway, S. Shafir, A. Allouche, E. Stern, R.A. Stern, Synergistic effects between bumblebees and honey bees in apple orchards increase cross pollination, seed number and fruit size, Scientia Horticulturae, Volume 219, 2017, Pages 107-117, ISSN 0304-4238, https://doi.org/10.1016/j.scienta.2017.03.010 [9] Nicholas J. Balfour & Sam Gandy & Francis L. W. Ratnieks, Exploitative competition alters bee foraging and flower choice. Behav Ecol Sociobiol (2015) 69:1731–1738 DOI 10.1007/s00265-015-1985-y [10] Vivian M Butz Huryn, Ecological Impacts of Introduced Honey Bees. The Quarterly Review of Biology, Vol 72, No. 3, September 1997. [11] For recent reviews see Jay M. Iwasaki and Katja Hogendoorn, (2022) Mounting evidence that managed and introduced bees have negative impacts on wild bees: an updated review. Current Research in Insect Science 2, 100043, https://doi.org/10.1016/j.cris.2022.100043 and, Mallinger RE, Gaines-Day HR, Gratton C, (2017) Do managed bees have negative effects on wild bees?: A systematic review of the literature. PLoS ONE 12(12): e0189268. https://doi.org/10.1371/journal.pone.0189268 [12] Victoria A. Wojcik, Lora A. Morandin, Laurie Davies Adams, and Kelly E. Rourke, (2018) Floral Resource Competition Between Honey Bees and Wild Bees: Is There Clear Evidence and Can We Guide Management and Conservation? [13] See Catherine Beard interviewed for Farah Hancock's The dark side of NZ’s honey bee, Newsroom's Ideasroom, 5th February 2018. Online at https://www.newsroom.co.nz/the-dark-side-of-nzs-honey-bee [14] Raphael K. Didham, Jason M. Tylianakis, Melissa A. Hutchison, Robert M. Ewers, Neil J. Gemmell, Are invasive species the drivers of ecological change? Trends in Ecology & Evolution, Volume 20, Issue 9, 2005, Pages 470-474, ISSN 0169-5347 [15] Jonah H. Peretti, (1998). Nativism and Nature: Rethinking Biological Invasion, Environmental Values, Vol. 7, No. 2, pp. 183-192 [16] Parker R, Melathopoulos AP, White R, Pernal SF, Guarna MM, et al. (2010) Ecological Adaptation of Diverse Honey Bee (Apis mellifera) Populations. PLoS ONE 5(6): e11096. doi:10.1371/journal.pone.0011096 [17] Carthey AJR, Banks PB (2012) When Does an Alien Become a Native Species? A Vulnerable Native Mammal Recognizes and Responds to Its Long-Term Alien Predator. PLoS ONE 7(2): e31804. doi:10.1371/journal.pone.0031804 [18] Michener, Charles D. (2000). The Bees of the World. Johns Hopkins University Press. pp. 19–25. ISBN 0-8018--6133-0. [19] Donovan, B. J. 2007. Apoidea (Insecta: Hymenoptera). Fauna of New Zealand, no. 57, Manaaki Whenua Press, Landcare Research ISBN 978-0-478-09389-6. [20] Parker R, Melathopoulos AP, White R, Pernal SF, Guarna MM, et al. (2010) Ecological Adaptation of Diverse Honey Bee (Apis mellifera) Populations. PLoS ONE 5(6): e11096. doi:10.1371/journal.pone.0011096 [21] G. C. Lye, O. Lepais and D. Goulson, Reconstructing demographic events from population genetic data: the introduction of bumblebees to New Zealand. Molecular Ecology (2011) doi: 10.1111/j.1365-294X.2011.05139.x [22] Buys, M.H., Winkworth, R.C., De Lange, P.J., Wilson, P.G., Mitchell, N., Lemmon, A.R., Moriarty Lemmon, E., Holland, S., Cherry, J.R. and Klápště, J., 2019. The phylogenomics of diversification on an island: applying anchored hybrid enrichment to New Zealand Leptospermum scoparium (Myrtaceae). Botanical Journal of the Linnean Society, 191(1). [23] Koot, E., Arnst, E., Taane, M., Goldsmith, K., Thrimawithana, A., Reihana, K., González-Martínez, S.C., Goldsmith, V., Houliston, G. and Chagné, D., 2022. Genome-wide patterns of genetic diversity, population structure and demographic history in mānuka (Leptospermum scoparium) growing on indigenous Māori land. Horticulture research, 9. [24] Ibid. Koot et al [25] Battersby PF, Wilmshurst JM, Curran TJ. et al. Exploring fire adaptation in a land with little fire: serotiny in Leptospermum scoparium (Myrtaceae). J Biogeogr. 2017;44:1306–18. [26] Gbedomon RC, Salako VK, Schlaepfer MA (2020) Diverse views among scientists on non-native species. NeoBiota 54: 49–69. https://doi.org/10.3897/neobiota.54.38741 [27] Townsend, Mike. (2005). Is the social construction of native species a threat to biodiversity? https://www.researchgate.net/publication/292358175_Is_the_social_construction_of_native_species_a_threat_to_biodiversity [28] Martin A. Schlaepfer, Dov F. Sax, and Julian D. Olden, Toward a More Balanced View of Non-Native Species. Conservation Biology, Volume 26, No. 6, 1156–1158 2012 Society for Conservation Biology. DOI: 10.1111/j.1523-1739.2012.01948.x [29] Sonia Shah, Native Species or Invasive? The Distinction Blurs as the World Warms, E360, January 14th 2020. https://e360.yale.edu/features/native-species-or-invasive-the-distinction-blurs-as-the-world-warms