Watch out for my article in Bees and Other Pollinators Quarterly Magazine about what the forthcoming COP26 climate change meeting has in store for pollinators, including why commitments to developing countries are important and the Grasslands+ initiative.
The magazine is in the shops on October 12th or you can subscribe by following this link: https://bq-mag.store/
At the end of August I was back in Copenhagen for a couple of days to take part in the PhD defence of Céline Moreaux, who has been working on coffee pollination and bee conservation. While I was there I snapped a couple more images for my Copenhagen Bestiary series. However I’ve also seen some interesting sculpture and building decoration further afield this month, in Aarhus, Silkeborg, and Nykøbing Sjælland. I especially like the wooden carved canopy support in the form of a duck, from Aarhus: it’s very subtle and I almost walked past it.
And before anyone asks, no, Karin and I are NOT part of the bestiary, but I didn’t get a shot of the troll by itself.
First the misleading title. This ‘debunks’ claim actually compares two different things: 75% of CROPS being dependent on pollinators versus 10% of crop YIELD. However, even if we focus on the 10% claim, a small increase in yield can be the difference between profit and bankruptcy for small-scale farmers. And most of the world’s farmers are small-scale and living on the borderline between loss and break-even. In addition, there’s no acknowledgement of the food production from home gardens, allotments, and community gardens, which is significant but largely unquantified.
Next, by focusing on yield and comparing, say, wind-pollinated wheat with insect-pollinated apples, the article takes no account of the fact that many of these crops that depend to some extent on pollinators mainly provide essential vitamins and minerals – not calories – to diets. When I tweeted about this earlier in the week, one person commented that they describe the insect-pollinated foods as ‘an important source of flavour and colour in our diets, rice and wheat are all well and good, but you do kinda need something more than grey slop to live’. Another said: ‘I’m so glad you mentioned this. I’m sick of reading articles that praise innovations to increase calories, when what we need is better nutrition from vitamins, minerals & fibres’.
Both great points, and well made.
That essay was also factually incorrect when it described roots crops such as carrots or some of the leafy cabbages and lettuces as not requiring pollinators. Many varieties of these crops ARE pollinator dependent: how do they think we get the seed for the next year’s crop?! And there are many crops and varieties that have not been evaluated for their dependency on pollinators: the 75% figure actually refers to the 115 most productive crop plants (Klein et al. 2007).
When I tweeted about the essay I commented that I was very disappointed by ‘Our World in Data’ – they are usually better than this when it comes to the facts. What I hadn’t appreciated at the time was that in fact the Genetic Literacy Project had highjacked the original piece by Hannah Ritchie and reworked it to give it a very different slant*.
This is where it starts to get dishonest and in fact the Genetic Literacy Project (GLP) has form in this area. The Sourcewatch site describes the GLP as ‘a corporate front group that was formerly funded by Monsanto’ with a remit to ‘shame scientists and highlight information helpful to Monsanto and other chemical producers’. In other words it’s heavily tied to Big Agriculture which, of course, would like us to believe that there’s not an issue with declining pollinators, that pesticides and agricultural intensification are our friends, and that Everything Is OK. Read the full account here.
Frankly, the GLP is so tainted that I’d not believe anything that they publish.
Pollinator decline and the role of pollinators in agriculture are complex issues. If you’d like to know more about the importance of pollinators to agriculture, complete with some accurate and objective facts, then there’s a whole chapter devoted to the topic in my book Pollinators & Pollination: Nature and Society.
*Note that I’ve been communicating with Hannah about the root and leaf crop issue and she accepts that this needs to change in the original. She’s also asked the Genetic Literacy Project to take down their version as it contravenes copyright.
Klein, A.-M., Vaissière, B.E., Cane, J.H. et al. (2007) Importance of pollinators in changing landscapes for world crops. Proceedings of the Royal Society of London B 274: 303–313.
As I mentioned in my previous post, it’s currently Invasive Species Week in the UK. Non-native species which have negative environmental impacts and disrupt infrastructure are a global phenomenon, of course, and almost all regions of the world have been impacted by species that originated elsewhere. One alien species that is of growing concern in Australia is the western honey bee Apis mellifera. We often think of bees as being relatively benign organisms, but a number of species have been introduced around the world and may compete with native species for nectar and pollen, and nesting sites.
In the second paper from my collaboration with Dr Kit Prendergast, we’ve assessed how introduced honey bees change the structure of bee-flower visitation networks in Australian urban habitats. The main finding is that when honey bees are common, they dominate these networks in ways that indicate significant competition with native bee species. You can get a sense of that from the figure above: the honey bees are in red, native bees in yellow, native plants in light green, and non-native plants in dark green. The length of the bars is proportional to the abundance of these plants and bees.
To say that honey bees ‘dominate’ these networks is an understatement: not only are they vastly more abundant than the other bees, but they visit almost all of the different types of flowers in the network, regardless of whether they are native or introduced.
Although the honey bee bullshit machine often claims that western honey bees are dying out, the exact opposite is true: across the world, managed Apis mellifera numbers are higher than ever, as you can see from the following chart based on figures from the United Nations Food and Agriculture Organization (UN-FAO):
Whilst the growth in honey bee numbers is a good thing for honey producers, bee farmers, and small-scale subsistence farmers, there are environmental consequences to the increase in hives, as we have shown.
If anyone wants a PDF of the paper, please use the Contactform. The full reference for the study and the abstract is:
The European honeybee Apis mellifera is a highly successful, abundant species and has been introduced into habitats across the globe. As a supergeneralist species, the European honeybee has the potential to disrupt pollination networks, especially in Australia, whose flora and fauna have co-evolved for millions of years. The role of honeybees in pollination networks in Australia has been little explored and has never been characterised in urban areas, which may favour this exotic species due to the proliferation of similarly exotic plant species which this hyper-generalist can utilise, unlike many native bee taxa. Here, we use a bipartite network approach to compare the roles, in terms of species-level properties, of honeybees with native bee taxa in bee-flower (‘pollination’) networks in an urbanised biodiversity hotspot. We also assessed whether the abundance of honeybees influences overall network structure. Pollination networks were created from surveys across seven residential gardens and seven urban native vegetation remnants conducted monthly during the spring-summer period over two years. There were consistent differences in species-level properties between bee taxa, with honeybees often differing from all other native bees. Honeybees had significant impacts on network properties, being associated with higher nestedness, extinction slopes of plants, functional complementarity and niche overlap (year two), as well as lower weighted connectance and generalisation. These associations all are indicative that competition is occurring between the introduced honeybee and the native bee taxa in bee-flower networks. In conclusion, the introduced honeybee occupies a dominant, distinct position in bee-flower networks in urban habitats in the southwest Western Australian biodiversity hotspot
Bottom line is that the global coffee production in 2019/20 was the result of 24 TRILLION flower visits by bees! That’s down a little from the previous year, but it’s still a LOT of visits by a HELL of a lot bees!
Humans affect the land on which they live in many different ways, and this in turn influences local biodiversity. Sometimes this has positive effects on local wildlife: consider the diversity of birds to be found in well-managed suburban gardens, for example. But often the effect is negative, especially when the land is intensively managed or habitats are destroyed, for example via deforestation or urban development.
This is not a new phenomenon – according to a recent study, most of the habitable parts of the planet have been shaped by humans for at least 12,000 years (see Ellis et al. 2021). What is new, however, is the scale and the speed with which land-use is changing, which are far greater than they have been historically. An important question is the extent to which this change in land-use intensity is affecting pollinator diversity in different parts of the world. Over the past 18 months I’ve been collaborating on a project led by Joe Millard (as part of his PhD) and Tim Newbold which uses the Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (PREDICTS) database to address that very question.
The study was global in scale and used data from 12,170 sites to assess the affect of land-use intensity on 4502 pollinating species. The findings are really fascinating; highlights include:
In comparison to natural vegetation, low levels of land-use intensity can have a positive effect on the diversity of pollinators.
For most land categories, greater intensity of land-use results in significant reductions in diversity and abundance of pollinators, however. For example, for urban sites there’s a 43% drop in number of species and a drop in 62% pollinator abundance from the least to the most intensive urban sites.
On cropland, strong negative responses of pollinators to increasing intensity are only found in tropical areas, although different taxonomic groups vary in their responses.
The latter finding is especially concerning given that: (i) most pollinator diversity is found in the tropics; (ii) the majority of tropical crops are insect pollinated; and (3) tropical agriculture is becoming increasingly intensive and land use is likely to rapidly change in the coming decades.
The full reference for the study, with all authors, is:
Millard, J., Outhwaite, C.L., Kinnersley, R., Freeman, R., Gregory, R.D., Adedoja, O., Gavini, S., Kioko, E., Kuhlmann, M., Ollerton, J., Ren, Z.-X. & Newbold, T. (2021) Global effects of land-use intensity on local pollinator biodiversity. Nature Communications 12, 2902. https://doi.org/10.1038/s41467-021-23228-3
The article focuses on some of the myths and misunderstandings that I dealt with in my book Pollinators & Pollination: Nature and Society. It also points out that, even in a place like Britain with a long tradition of natural history study, there’s still much for the patient observer to discover. If you’re interested in a PDF, drop me a line via the Contact page.
I meant to post about this earlier but it’s been a really busy few weeks, so apologies if this is late in the day for any of you. Tomorrow morning there’s a webinar being run by the Public Policy Exchange entitled: “Protecting British Pollinators”. There’s an interesting set of speakers and I’ve been asked to provide the opening introduction and to chair the event.
Here’s the link for more details and booking information:
I had an interesting conversation with a landscape architect on Wednesday who was asking for some advice about creating urban habitat for pollinators. The plan was to strip turf from under the trees in a city greenspace in order to put in some flowering plants as nectar and pollen sources. I often get asked about this, not only by landscape architects, but by professional gardeners, park committees, local residents groups, and so forth. My initial advice, following the Greek physician Hippocrates, is always the same:
“First, do no harm.”
Hippocrates was of course speaking to doctors and saying: before you intervene in a patient’s health, make sure you are not making things worse for them.
So what do I mean by this? Why is it relevant to pollinators?
Well, in the case of the discussion from earlier this week, the team had no idea if there were ground nesting bees such as Andrena spp. in the area where they planned to strip the turf. Stripping the turf would likely have destroyed any nests, or at least prevented the bees from emerging, particularly if a thick mulch was applied to the area. There were also suggestions of using glyphosate to kill off the grass, though I certainly advised against it: by coincidence a meta-analysis by Lucas Battisti and colleagues was published this week showing categorically that glyphosate is toxic to bees. Imagine spraying it over an area that has a colony of one of the ground-nesting solitary species? Or where queen bumblebees might be hibernating? Queen Bombus spp. often hibernate close to the base of trees – see D.V. Alford’s classic 1969 study of bumblebee hibernation.
It’s not only pollinators that could be harmed by starting work without appropriate surveys: even unpromising-looking municipal grassland, for example in parks, can harbour a significant diversity of plants that are being suppressed by too-frequent mowing. Mow less often and they will flower, producing nectar and pollen for pollinators, then later seeds for birds.
Sometimes you can do more by doing less.
One of the things that I stress in my book Pollinators & Pollination: Nature and Society, is that habitat creation for pollinators is about much more than just planting wild flower meadows and putting up some bee hotels. It needs forethought about what is on a site already, and what may be destroyed by the proposed actions. There also needs to be a consideration of the wider landscape context in which the proposed site is situated, and whether it is providing some of the other things that pollinators need to complete their life cycles each year. The diagram above is from my book and I refer to it as the “Requirements of Pollinators Triangle”. Because pollinators are so diverse in their natural histories, no one site can hope to provide everything that they all need. However there are some general principles that I present in the book.
If you’d like to know more about any of this, or need advice, or to enquire about the training that I offer, please do get in touch via my Contactpage.
Over the past few months I’ve done a large number of online talks for a variety of audiences, including natural history and gardening societies, beekeeping groups, private companies, university estates departments, and ecological consultancies. I thought it would be useful to provide a list of what I offer, with a short description. All talks are accessible and understandable to a broad audience, and can be tailored to the individual needs of the group:
Pollinators & Pollination: Nature and Society is an introduction to the importance of pollinators and the pollination services that they provide to both wild and crop plants. The name, of course, reflects that of my recent book.
The Politics of Pollination is an account of how society (governments, organisations and individuals) has responded to the current “pollination crisis” (if that’s what it actually is…)
Bees in Cities: an Introduction to Urban Pollinatorsfocuses on the positive roles that urban environments can play for pollinators, and the potential threats of city living.
Pollinators in Gardens gives practical advice on how to make your garden “pollinator friendly”.
Pollinator Conservation: Threats and Opportunities describes how and why pollinators are declining and what we can do about it at the individual and societal level.
Habitat Creation and Management for Pollinators gives an introduction to how NGOs, estates departments, consultancies, and so forth, can effectively support pollinators in ways that go beyond just planting flowers and putting up a few “bee hotels”.
To Be a Flower is an introduction to how flowers function and the ways in which they manipulate the behaviour of their pollinators to ensure reproduction.
Darwin’s Unrequited Isle: a Personal Natural History of Tenerife describes some of the field work that we’ve been doing on this most fascinating of the Canary Islands.
Biodiversity: What Is It and Why Should We Care? gives a very general overview of the topic of biodiversity and ecosystem services.
Talks typically last for around 50 minutes, following which I’m happy to answer questions and discuss any issues that have arisen. I also offer a half- or full-day of training for those organisations that need more depth, for example ecological consultancies. Note that I charge for all of my talks and training. If you would like to enquire about any of this, please use the form on the Contact page.