Category Archives: Honey bees

Get a 30% discount if you pre-order my new book Pollinators & Pollination: Nature and Society


In the next few months my new book Pollinators & Pollination: Nature and Society will be published.  As you can imagine, I’m very excited! The book is currently available to pre-order: you can find full details here at the Pelagic Publishing website.  If you do pre-order it you can claim a 30% discount by using the pre-publication offer code POLLINATOR.

As with my blog, the book is aimed at a very broad audience including the interested public, gardeners, conservationists, and scientists working in the various sub-fields of pollinator and pollination research. The chapter titles are as follows:

Preface and Acknowledgements
1. The importance of pollinators and pollination
2. More than just bees: the diversity of pollinators
3. To be a flower
4. Fidelity and promiscuity in Darwin’s entangled bank
5. The evolution of pollination strategies
6. A matter of time: from daily cycles to climate change
7. Agricultural perspectives
8. Urban environments
9. The significance of gardens
10. Shifting fates of pollinators
11. New bees on the block
12. Managing, restoring and connecting habitats
13. The politics of pollination
14. Studying pollinators and pollination



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Filed under Bees, Biodiversity, Biodiversity and culture, Birds, Butterflies, Climate change, Ecosystem services, Evolution, Flies, Gardens, History of science, Honey bees, Hoverflies, IPBES, Macroecology, Mammals, Moths, Mutualism, Neonicotinoids, Personal biodiversity, Pollination, Rewilding, Tenerife, Urban biodiversity

For World Bee Day – an extract from my forthcoming book – UPDATED


UPDATE: turns out the figure I cited for number of bee species is out of date so I’ve corrected it below. Thanks to John Ascher for pointing this out.

Publication of my book Pollinators & Pollination: Nature and Society by Pelagic Publishing has been pushed back until the end of this year or early in 2021. The current pandemic has created problems for the printing and distribution sectors, as it has for so many industries. Therefore, to celebrate World Bee Day, here’s a preview of the bee section from Chapter 2 which is entitled (ironically enough) “More than just bees – the diversity of pollinators”.

2.3 Bees, wasps and sawflies (Hymenoptera)

The bees and their relatives rank only third in terms of overall pollinator diversity.  Within this taxonomic Order, bees are not especially species rich (17,000 or so described species, perhaps 20,000 in total) – over 20,400 (see: compared with the other 50,000 social and solitary wasps, sawflies, and so forth. But what they lack in diversity the bees make up for in importance as pollinators of both wild and agricultural plants, and in their cultural significance.  The general notion of what a bee is, and how it behaves, looks to the honeybee (Apis mellifera) as a model: social, with a hierarchy, a queen, and a large nest (termed a hive for colonies in captivity).  In fact, this view of bee-ness, though long embedded within our psyche, is far removed from the biology of the average bee: most of them have no social structure at all, and a fair proportion of those are parasitic.  In Britain we have about 270 species of bees, give or take (Falk 2015) though there have been extinctions and additions to this fauna (see Chapters 10 and 11).  These species provide a reasonable sample of the different lifestyles adopted by bees globally.  They can be divided into four broad groups.

Honeybees include several highly social species and subspecies of Apis, of which the ubiquitous western honeybee (A. mellifera) is the most familiar.  Most colonies are found in managed hives, though persistent feral colonies can be found in hollow trees, wall cavities, and other suitable spaces.  They are widely introduced into parts of the world where they are not native (e.g. the Americas, Australia, New Zealand) and there is some debate as to whether they are truly native to Britain and northern Europe, with supporting evidence and arguments on both sides.  Colonies can be enormous and contain thousands of individuals, mostly female workers, with a single queen.  Unmated queens and males (drones) are produced by the colony later in the season.

Bumblebees (Bombus spp.) are typically also social, though their nests are much smaller (tens to hundreds of individuals).  Depending upon the species these nests can be in long grass, rodent holes, or cavities in buildings and trees.  Twenty-seven of the more than 250 species have been recorded in the UK, but six of these are not strictly social; they are parasitic and belong to the subgenus Psithyrus which will be described below.

The so-called solitary bees are by far the largest group in Britain (about 170 species) and worldwide (more than 90% of all species).  In the UK they belong to 15 genera, including Andrena, Anthophora, Osmia, Megachile, etc.  The females of most of these bees, once they have mated, construct nests that they alone provision with pollen for their developing young.  Nesting sites can be genus- or species-specific, and include soil, cavities in stone or wood, and snail shells.  Some species are not strictly solitary at all and may produce colonies with varying levels of social structure, though without a queen or a strict caste system; we term them “primitively eusocial”.  In fact sociality has evolved and been lost numerous times in the bees and in the rest of the Hymenoptera (Danforth 2002, Hughes et al. 2008, Danforth et al. 2019).  It’s also been lost in some groups that have reverted back to a solitary lifestyle, and even within a single genus it can vary; for example in the carpenter bee genus Ceratina (Apidae: Xylocopinae) tropical species are more often social than temperate species (Groom & Rehan 2018).

The final group is termed the cuckoo bees and, like their avian namesake, they parasitise the nests of both social and solitary bees (though never, interestingly, honeybees).  There are about 70 species in 7 genera, including the bumblebee subgenus, Psithyrus.  Other genera include Melecta, Nomada and Sphecodes.  In some cases the parasitic species are closely related evolutionarily to their hosts and may resemble them, for example some Psithyrus species.  In other cases they may be only distantly related and in fact look more like wasps, e.g. Nomada species.  Some genera of cuckoo bees are restricted to parasitising only a single genus of bees, others are parasites of a range of genera (Figure 2.4).

Although we often think of bees, overall, as being the most important pollinators, in fact species vary hugely in their importance.  Pollinating ability depends upon factors such as abundance, hairiness, behaviour, body size, and visitation rate to flowers (Figure 2.1).  Size is especially important for three reasons.  First of all, larger animals can pick up more pollen on their bodies, all other things being equal.  Secondly, in order to bridge the gap between picking up pollen and depositing it, flower visitors must be at least as large as the distance between anthers and stigma, unless they visit the stigma for other reasons.  Finally, larger bee species tend to forage over longer distances on average (Greenleaf et al. 2007) thus increasing the movement of pollen between plants.  However, most of the world’s bees are relatively small as we can see from the analysis of British bees in Figure 2.5.  Many species have a maximum forewing length of only 4 or 5 mm, and the majority of species are smaller than honeybees.  Remember also that these are maximum sizes measured from a sample; individual bees can vary a lot within populations and even (in the case of Bombus spp.) within nests (Goulson et al. 2002).  So the assumption that all bees are good pollinators needs to be tempered by an acknowledgement that some are much better than others.    

Figure 2.5: The sizes of British bees. Forewing length is a good measure of overall body size and the data are maximum lengths recorded for species, except for the social bumblebees and honeybee I have used maximum size of workers (queens are often much larger). The blue line indicates the honeybee (Apis mellifera). The biggest bee in this data set is the Violet Carpenter Bee (Xylocopa violacea) which, whilst not generally considered a native species (yet), has bred in Britain in the past. Data taken from Falk (2015).

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Filed under Bees, Biodiversity, Ecosystem services, Honey bees, Pollination, Wasps

Garden plant-pollinator surveys: progress so far

The network of pollination ecologists and insect specialists who have confirmed that they are surveying plant-pollinator networks in their gardens now stands at 50. As the map above shows, most are in the UK, Ireland and mainland Europe, but the Americas are also becoming well represented, we have a couple of people surveying in North Africa, and three in Australia. An x-y plot of the coordinates of the gardens shows the spread a little better:

Some people have started to send me data already, which is great; if you’re surveying and haven’t let me know your latitude and longitude, please do so, preferably decimalised – you can convert degrees/minutes/seconds to decimal here:

I’ve managed 13 formal 15 minute surveys so far, plus have a few ad hoc observations that I am keeping separate, and I will be continuing my data collection for the foreseeable future. I’ve started playing with the data as you can see below. This is a plot made using the bipartite package in R, with plants to the left and pollinators to the right. The size of the bars is proportional to the number of pollinators/plants a taxon connects to. In the plants you can immediately see the dominance of apple (Malus domestica) and greengage (Prunus domestica), which attract a wide variety of insects to their flowers. Of the pollinators, the hairy-footed flower bee (Anthophora plumipes) and dark-edged beefly (Bombylius major) are especially common and generalist in their flower visits. It will be really interesting to see how this changes over the season, and how our fruit and vegetables are connected into the wider network via pollinators that they share with the ornamental and native plants.

If you are experienced at surveying pollinators and want to get involved, follow that first link and check out the protocol and FAQs, and please do email me: jeff.ollerton [at]


Filed under Bees, Biodiversity, Butterflies, Ecosystem services, Flies, Gardens, Honey bees, Hoverflies, Pollination, Urban biodiversity

Pollination ecologists in gardens: protocol and links to other initiatives – UPDATE NUMBER 2

Andrena bicolor

UPDATE: Following conversations with a couple of the participants of the garden surveys, we’ve changed the protocol slightly to make Survey type A more quantitative and to take into account when we get large numbers of individuals all visiting the same plant at the same time – it’s crazy to have a single line for each individual.  Details are in the new spreadsheet which you can down load from here: Ollerton garden surveys 2020

The additions should be self explanatory.  If you are not able to go back to retro-fit the additional data, that’s fine, just use the new spreadsheet format for future surveys: all data are going to be useful!

In the present format the data will be useful for modelling using GLMMs etc., in order to test predictions about which plants, and in which contexts, support the most pollinators.  The data format will need tweaking slightly to make it analysable in bipartite, but that should be fairly straightforward.

If you are taking part in the surveys it would be really useful if you could email me your latitude and longitude as I’d like to start creating a map of where the surveys are happening.

Any questions, send me an email or ask in the comments.


Following up from my last post about ecologists using their gardens to collect standardised data, I’ve had a huge response from pollination ecologists all over the world wanting to get involved.  So to streamline the process I thought that I would put the protocol and updates on my blog.  Just to reiterate, this is really is designed for those who already have some experience of surveying pollinators and flowers.  I didn’t intend this to be a citizen science project, there are plenty of those around at the moment for inexperienced people who want to contribute, for example:

The Pollinator Monitoring Scheme’s  FIT (Flower-Insect Timed) counts:

Kit Prendergast’s “bee hotels” survey:

If anyone wants me to publicise others, let me have the link in the comments below or send me an email.

OK, for those ecologists wanting to survey pollinators and the flowers they are visiting (or not visiting) in their gardens, here’s the protocol:

  1.  There are two types of survey – please do both if possible, it would be good to compare the results from the two approaches; otherwise choose the easiest one for you.
  2. Type A surveys involve regular walks at a steady pace around the garden, recording what insects and other flower visitors are active on particular flowers (and noting the ones they are not visiting).  Make your walks a standard time, proportional to the size of the garden. For example, in our 10m x 20m garden I am doing 15 minute walks, which involves walking the same route one way, then back, pausing to record data.
  3. Type B surveys involve 10 minute focused observations of a patch of flowers of one species, no larger than 0.5m x 0.5m, recording the number of flowers each pollinator visits.
  4. In both cases, identify the flower visitor to the taxonomic level to which you feel confident, e.g. it’s better to use Andrena sp. 1 or Calliphoridae sp. 2 or Diptera sp. 3 rather than guessing.
  5. Record all data plus metadata about your garden on this spreadsheet which has examples of data that I have collected so far.  When you return it, please change “Ollerton” to your own surname : Ollerton garden surveys 2020
  6. Please don’t modify the format of the survey sheets, it will make life very difficult when we collate the data.
  7. Collect data from now until the end of April.  By then we will know whether to continue further data collection.
  8. At the end of the month, send your spreadsheets to me: jeff.ollerton [at]  I will acknowledge receipt of each one, so if you don’t get an acknowledgement it may be that our spam filter has rejected your email, in which case message me on Twitter or comment below.
  9. Finally – please respect local/national restrictions on movements and social isolation: safe safe and keep your community safe.


Here are some Frequently Asked Questions – I will update FAQs as they come in:

Q: What’s going to happen to all of the data?

I think that’s for the pollinator research community to decide.  My feeling at the moment is that in the first instance there should be a data paper that summarises the results and makes the data freely available to everyone.  That would include all data contributors as co-authors, probably under a project name rather than individually.  After that it’s up to individuals and groups to work with the data to address their own research questions.  I know that in the UK there are several PhD researchers who are worried about not being able to collect data this year and who want to contribute to this initiative and use it in their theses.  I’m sure that there are others elsewhere.  As a community it would be great to support these young researchers.

Q: I am not based in the UK, can I still take part?

A: Yes, of course, though check in your local networks to see if anyone is coordinating local efforts.

Q: How do I calculate “Total floral cover” for survey Type B?

A: The idea is to estimate the area covered by all of the patches of the plant in flower across the whole garden, and then add it up to get a total area covered. It is always going to be a rough estimate, but it at least gives us a sense of how abundant the flowers are in your garden.

Q: How do I classify “floral units” for survey Type B?

A: Use the UK POMS approach:

POMS flower heads

Q:  Should I collect weather data?

A: You can certainly add data to another sheet on the spreadsheet if you want to, but the plan is to use data from local weather stations to capture standardised weather information.

Q: Should I collect nectar and/or pollen and/or pollinator behaviour data?

A: Again, collect any data that you have the time and equipment for and add it to a different sheet

Q: My garden has very few flowers and pollinators – can I still take part?

A: Yes, absolutely, we need a range of garden types, from the very large and florally diverse to small window boxes or lawns with just daisies and dandelions..

Q: How long should I survey for, and how many surveys should I do.

A: Try to aim for what you think is a representative assessment of the plant-flower visitor network in your garden.  The idea is that people do as many surveys as they can, as often as they can, given their personal time constraints. I don’t want to dictate to people how to use their time, this needs to be enjoyable as well as useful. As long as we know the sampling effort and floral diversity within the gardens, we should be able to take account of sampling effort in any analyses.


Filed under Bees, Biodiversity, Butterflies, Gardens, Honey bees, Hoverflies, Moths, Pollination, Urban biodiversity

Feral bees in odd places; Australia reflections part 7

On a trip to the Royal Botanic Gardens Sydney yesterday Karin and I came across an interesting colonial-era statue in which a colony of feral, non-native honey bees had taken up residence.  These bees are yet another alien invasive species that can create conservation problems in parts of the world where they don’t belong naturally.  But it was funny enough to inspire a bit of Ogden Nash-style poetry on Twitter; you need to watch the video to fully appreciate it:


Filed under Australia, Bees, Honey bees, Poetry

More on historical honey bee numbers in Britain

Bees hives with earlier data points - 18th Nov

Following on from my post last week on historical changes in honey bee numbers in Britain, I decided to add the two extra, earlier data points to the graph just to illustrate what they mean for our understanding in how honey bee numbers may (or may not) have changed over the last 100 years.

The first data point is the Bailey & Perry (1982) estimate of 800,000 hives in the 1920s (which I’ve placed at 1929) that, as I mentioned, I think is wrong in terms of how they did the calculation.

The second data point is of 32,500 hives in 1919.  It’s from the article that Andrew Hubbard drew my attention to, which seems to be a fairly solid government statistic, or at least no less solid that much of the other government stats (unless anyone knows any better).

If we accept the 800,000 figure at face value then we see a massive increase in number of hives of over 76,000 new hives per year between 1919 and 1929.  And remember that’s being conservative as to what “the 1920s” meant to Bailey & Perry; if we peg the date at 1925 then we’re talking more than 127,000 hives being added to the British stock every year.  In my opinion that’s not a feasible proposition.

A much more likely scenario is that the number of hives grew during the second quarter of the 20th century and reached a peak in numbers at some point between the 1940s and 1950s.  That’s an increase of around 13,000 hives per year.  It’s still a lot, but is not unreasonable in light of post-World War 1, and subsequently World War 2, agricultural reforms that I highlighted in my post about British bee and flower-visiting wasp extinctions.   I’ve termed that “Jeff’s speculation” in the figure above because, in the absence of hard data, that’s all it can be.

As always, I welcome your comments.



Filed under Bees, Biodiversity, Honey bees

Historical changes in honey bee numbers in Britain – how much do we know? UPDATED

Bee hives figure - 12 November

UPDATE:  On Twitter, Andrew Hubbard kindly drew my attention to the short article from 1919 at the bottom of this post in which it was estimated that British bee stocks at the time were as low as 32,500 hives.  As Andrew pointed out, this means that the estimate by Bailey and Perry of 800,000 hives in the 1920s cannot be correct.


In one of the chapters of the book that I’m currently completing I deal with the question of the evidence for changes in the abundance and diversity of pollinators over time, both in Britain and globally.  Are we really in danger of losing most of our pollinator species?  Have honey bee numbers plummeted?  Has pollination of wild and crop plants been affected?  The evidence is mixed and too complex to deal with in a short blog post: you’ll have to read the book 🙂  However I want to present some data that I’ve collated on changes in honey bee hives in Britain to gauge opinions on what has gone on.  I’m not a specialist in bee keeping by any means, others are far more knowledgeable, so as always I’d be interested in peoples’ thoughts on this.

The graph above has been pieced together from data presented in various sources – see below.  From a post-WW2 peak of about 450,000 hives, numbers dropped to about 150,000 hives in the 1970s.  That seems very clear.  Numbers remained fairly stable until the early 1990s and then….what?  There are two possibilities: either numbers of hives crashed to fewer than 100,000 by 2008; or they increased hugely to more than 250,000.  Both scenarios cannot be correct!

There are huge uncertainties about the data during this period, however the most recent data from Defra is fairly solid, though it does require beekeepers to register their hives on BeeBase.   Given the wide range of the low and high estimates, the fact that bee keeping has become more popular over the past decade, and that the recent data sit more-or-less within this range (at least initially), I wonder whether honey bee numbers have actually remained quite stable over the past 25 years or so, and indeed have hovered around the 150,000 hives or so since the 1970s.

Of course an alternative scenario is that the varroa mite (which arrived in Britain in 1992) led to that huge collapse in bee numbers.  But I wonder if there’s really any evidence for that?  Were whole apiaries wiped out by varroa?  It’s notable that the decline in this period started much earlier than the arrival of varroa, in 1985.  Why was that?

Data sources:

The earliest data available are those in Bailey & Perry (1982 – Bulletin of Entomological Research 72: 655-662) that span 1946-1982. This should be fairly accurate for England and Wales, though their estimate of 800,000 hives in the 1920s needs to be treated with caution as they make a number of assumptions in their regression-based analysis that may be incorrect; I’ve therefore not included that data point on the graph. Unfortunately the UK stopped returning official numbers of hives to the United Nations’ Food and Agriculture Organisation (UN-FAO) in 1977, and their data up to 1987 is an unofficial estimate ( From 2003 the UK had to report bee hive numbers to the European Union to claim money for the National Apiculture Programme (, but the figures were rather suspiciously constant between years. More recently beekeepers have been encouraged to register their hives with BeeBase ( and hopefully these estimates are more realistic.

Data for part of this period were also presented in Potts, S.G. et al. (2010) Declines of managed honeybees and beekeepers in Europe? J. Apic. Res. 49, 15–22  Thanks to Prof. Simon Potts for sharing the data from that study.

Britsh Bee Journal 1919 - from Andrew Hubbard


Filed under Bees, Biodiversity, Honey bees

Bees and beer in London: an urban beekeeping experience

2019-07-28 11.18.31-1-1

One of our Christmas presents from Karin’s son (my stepson) Oli and his girlfriend Kate was an “experience” – a chance to spend half a day with an urban beekeeping collective in London called Bee Urban.  The group has a partnership with Hiver Beer which uses its honey in its brewing, and we were promised a tasting session.  Bees, beer, London – what’s not to like?  Karin and I finally made the trip down to Kennington yesterday and it was a really enjoyable experience, highly recommended.  I know a little bit about beekeeping but it was great to see a small professional apiary at work and to take part in a hive examination.  It certainly deepened my appreciation of these remarkable insects.  It also made me think about having a hive or two when I retire and have the time to devote to the hobby – beekeeping is not to be entered into lightly!  However there’s a time and a place for honeybees: in the wrong setting they can be a conservation problem by negatively affecting plant reproduction, out-competing native bees and passing on their diseases to bumblebees.

Bee Urban, however, is also doing its bit for wild bees in London by providing opportunities, such as drilled logs, for cavity nesting species.  We saw lots of evidence that leaf-cutting bees (Megachile spp.) and those that seal their nests with mud (various genera) were taking advantage of these nesting sites.

Interestingly, one of the other attendees said at the outset that she was very scared of bees.  I asked her afterwards if seeing beekeeping up close had helped and she said it had.  Perhaps this is something that you could do with any insectophobes in your life?

The beer was great, by the way, also highly recommended!

Below are some pictures from the day.  Thanks to Lena and Barnaby for hosting us and making it such an enjoyable experience.

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When she saw this picture, Karin likened it to cult devotees attending a ritual – “All Hail the Bee Goddess!”:

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2019-07-28 10.50.20

Karin and I get up close and personal with the bees:

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2019-07-28 10.55.30

A real highlight of the day – seeing the queen of this hive (marked in red):

2019-07-28 11.15.11

Yum! – :

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Drilled logs being used by leaf-cutting bees (Megachile spp.):

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2019-07-28 12.10.44


Filed under Bees, Biodiversity, Honey bees, Urban biodiversity

Beekeeping at 7000 ft: Nepal field work part 4

On the last day of field work, while we were waiting for a bus to take us back down to Kathmandu, I spotted some small bee hives next to one of the houses belonging to the local Tamang peoples:

2019-03-29 08.46.24

With a few minutes to spare before the bus left, I quickly investigated and discovered that only one of the hives was actually in use:

But interestingly, the bees inside where the native Asiatic or eastern honeybee (Apis cerana) rather than the European or western honeybee (A. mellifera) that is more familiar in Europe.  The bees are a bit smaller and more distinctively striped than their western counterpart:

2019-03-29 08.48.34-1

There didn’t seem to be much around for the bees to forage on, just a few flowering mustard plants, so I suspect that they were travelling some distance to find nectar and pollen:

2019-03-29 08.47.28

At this altitude of 2092 masl, or about 7000 feet, the winters are long and cold and the summers dry and hot, so the bees must be tough if they are kept there all year round.  I wonder if A. mellifera would survive these conditions?

All too soon the bus driver sounded his horn and it was time to go; an interesting encounter with a bee species I’d not previously seen.



Filed under Biodiversity, Honey bees, University of Northampton

Recent reviews in pollination biology: an annotated list: UPDATED x 3

2019-02-09 13.47.49

As it’s my birthday today, I thought I’d reward myself by completing a blog post that I started just after Christmas and never got round to finishing.  Review articles that summarise recent developments in a field are an important contribution to the scientific literature that allow us to pause and reflect on where a topic has been and where it is headed.  Having recently (co)authored a couple of reviews I can attest that they are useful in this respect for both the writers and for the readers.

In the past couple of years quite a number of critical and timely reviews have been published which are proving very useful to me: I’m currently writing a book and these reviews have been invaluable in summarising aspects of a field that is currently publishing in excess of 1000 research papers per year. So I thought I’d bring them together into a single listing with a short commentary on each.  No doubt I have missed many other reviews so please feel free to point out any gaps and I will update the list as I go along.

Each review is hot linked to the source; a good proportion of the reviews are open access, notably those from the recent special issue of Annals of Botany devoted to the ecology and evolution of plant reproduction.  Some reviews are very focused, but most are quite broad.  Several of these complement one another.  I hope you find them interesting and useful.

Barrett, S. & Harder, L. (2017) The ecology of mating and its evolutionary consequences in seed plants. Annual Review of Ecology, Evolution and Systematics 48: 135-157

Mating systems, i.e. who breeds with whom, are just as complex in plants as they are in animals.  However some features of seed plants, such as the fact that they don’t move, that most species have both male and female functions, and that their growth is modular and often indeterminate, represent significant challenges that have been overcome in a bewildering variety of ways.


Braun, J. & Lortie, C.J. (2018)  Finding the bees knees: A conceptual framework and systematic review of the mechanisms of pollinator-mediated facilitation.  Perspectives in Plant Ecology, Evolution and Systematics 36: 33-40

In a community, if one plant species positively affects another, we term this “facilitation”.  It can occur at a variety of life stages, including reproduction whereby the presence of one species increase the likelihood of another species being pollinated.  This review shows that it occurs fairly frequently at a variety of spatial scales, but there are still significant gaps in our understanding of the phenomenon.


Fuster, F., Kaiser‐Bunbury, C., Olesen, J.M. & Traveset, A. (2018) Global patterns of the double mutualism phenomenon. Ecography

When species provide benefits to one another in two different ways, for example an animal is both a pollinator and a seed disperser of a plant species, we refer to it as a “double mutualism”.  As this fascinating review shows, double mutualisms are very uncommon, but they are widespread, and probably under-recorded.


Minnaar, C., Anderson, B., de Jager, M.L. & Karron, J.D. (2019) Plant–pollinator interactions along the pathway to paternity. Annals of Botany 123: 225-245 

The male aspect of plant reproduction, i.e. pollen donation, is often neglected when we consider how pollination systems evolve.  This review provides as up to date account of where we are in understanding how paternity influences floral characters such as shape and colour.


Ollerton, J. (2017) Pollinator diversity: distribution, ecological function, and conservation. Annual Review of Ecology, Evolution and Systematics 48: 353-376

A very broad over view of our current understanding of the biodiversity of pollinators, taking a deep time and a wide spatial perspective to put current concerns about loss of pollinators into a wider perspective.


Parachnowitsch, A.L., Manson, J.S. & Sletvold, N. (2019) Evolutionary ecology of nectar. Annals of Botany 123: 247–261 

We often take nectar for granted – it’s just sugar and water, isn’t it?  As this review shows, nectar is dynamic and complex, and affects a range of ecological functions beyond just providing pollinators with a reward.  However there’s still a huge amount we don’t understand about how nectar traits evolve.


Toledo-Hernández, M., Wangera, T.C. & Tscharntke, T. (2017) Neglected pollinators: Can enhanced pollination services improve cocoa yields? A review.  Agriculture, Ecosystems and Environment 247: 137-148

Chocolate is most people’s favourite confectionery and is famously pollinated only by small midges.  Or is it? As this review shows, lots of other insects visit cocoa flowers, but their role as pollinators has not been well studied.


Vizentin-Bugoni J, PKM Maruyama, CS Souza, J Ollerton, AR Rech, M Sazima. (2018) Plant-pollinator networks in the tropics: a review. pp 73-91 In Dáttilo W & V. Rico-Gray. Ecological networks in the Tropics. Springer.

This book chapter that I co-authored with some very energetic and creative young Brazilian researchers summarises what’s currently known about plant-pollinator interaction networks in tropical communities.  One of the conclusions is that they are really not so different to those in temperate and subtropical biomes.


Wright, G.A., Nicolson, S.W. & Shafir, S. (2018) Nutritional Physiology and Ecology of Honey Bees. Annual Review Entomology 63:327-344

A review of how bees use nectar and pollen at the level of both the individual and the colony, focused on the most widespread of pollinator species.


As expected, several people have told me about reviews I’d missed, and in some cases ones that I had read but forgotten about!  I’ll list them below, though without annotations:

Bennett, J. et al. (2018) A review of European studies on pollination networks and pollen limitation, and a case study designed to fill in a gap, AoB Plants 10:

Knight, T. et al. (2018) Reflections on, and visions for, the changing field of pollination ecology. Ecology Letters 21: 1282-1295

Vallejo-Marin, M. (2018) Buzz pollination: studying bee vibrations on flowers. New Phytologist



I had deliberately restricted the reviews to 2017 onwards, but via email David Inouye kindly sent a few older ones through which are equally useful:

Brosi, B. J. (2016) Pollinator specialization: from the individual to the community. New Phytologist: 210: 1190–1194

Hahn, M. and C. A. Brühl (2016) The secret pollinators: an overview of moth pollination with a focus on Europe and North America. Arthropod-Plant Interactions: 1-8

Inouye, D. W., et al. (2015) Flies and flowers III: Ecology of foraging and pollination. Journal of Pollination Ecology 16



A more recent addition to this set of reviews was sent to me by Anne-Laure Jacquemart.  Although it’s focused just on one (rather variable) crop, I think it will be really useful for anyone interested in the pollination biology of crop plants:

Ouvrard, P. & Jacquemart, A.-L. (2019) Review of methods to investigate pollinator dependency in oilseed rape (Brassica napus).  Field Crops Research 231: 18-29





Filed under Bees, Biodiversity, Brazil, Honey bees, Mutualism, Pollination