Category Archives: Biodiversity

The coltsfoot is flowering! But why is it so different to dandelion?

Yesterday Karin and I took to our bikes and rode south through some very nice, managed beech and oak woodland that runs parallel to the Isefjorden in this part of Odsherred. In was cold but sunny, birds were singing, and we saw the occasional insect on the wing. The kind of day that reminds you that spring is coming fast. On the way back we paused at a small housing development near the former psychiatric hospital at Annebergparken. In an area of disturbed ground I was delighted to see a patch of coltsfoot (Tussilago farfara) in full flower, the dandelion-like inflorescences a beacon to passing bees and flies.

Although it resembles a small dandelion, and belongs to the same family (Asteraceae), Tussilago is only distantly related to Taraxacum. Coltsfoot is really a type of groundsel (tribe Senecioneae) whereas dandelions are related to chicory (tribe Cichorieae).

Coltsfoot is unusual in that it produces its flowering stems long before the leaves that give it its common name, the plant’s reproduction powered by the energy that it stored up the previous year. Dandelions, like most herbaceous plants, produce their leaves first, then flower. That’s not the only difference to dandelions though.

The Database of Pollinator Interactions (DoPI) lists 9 species of insect that have been recorded as visiting coltsfoot for nectar and/or pollen. In contrast, the entry for Taraxacum officinale lists more than130 species as flower visitors. I thought initially that it might be due simply to under-recording, but this study of coltsfoot in Germany only recorded 16 insect species. So the greater attractiveness of dandelion is likely to be real. Why the big difference in pollinators?

One reason for it could be that dandelions have a very different flowering strategy; they can be in flower 12 months of the year, depending on local weather conditions, with a reproductive peak in May or June. They therefore have the opportunity to interact with many more insects than coltsfoot, which in contrast you generally only see in flower between March and May at the very latest.

Dandelions are also much more abundant than coltsfoot which is no doubt also a big factor in determining how often insects are observed on the flower heads. It’s not unusual to see whole fields full of dandelions in flower but I’ve never seen coltsfoot do that, perhaps because they prefer to grow on rather disturbed ground.

There may be some other factors at play here that I’m not aware of, for example a lower rate of nectar production in coltsfoot. Having said that, the fact that dandelions produce any nectar at all is a real conundrum. All of the literature claims that Taraxacum officinale is “apomictic“, a plant reproductive strategy in which seeds are produced without requiring ovules to be fertilised by pollen. In fact the online Ecological Flora of Britain and Ireland entry for dandelions lists the pollen vector as “none” for that very reason. But I’m sure that the real story is more complicated, otherwise why would these plants invest so much of their energy and resources in attracting and rewarding flower visitors? I’ve not delved deeply into the Taraxacum literature so perhaps one of my readers knows?

Our encounter with coltsfoot reminded me of the work that I did last year with the Stanwick Lakes nature reserve in Northamptonshire, advising on how best to enhance and manage the site (which is primarily a bird reserve) for pollinators. One of my recommendations was that they enlist their volunteers to collect seeds and root or stem cuttings from the small, isolated populations of early-flowering plants such as coltsfoot (pictured on the reserve below) and introduce them around the site in suitable spots. This would both increase the availability of nectar and pollen for the first flower visitors of spring, and also the ecological connectivity between different parts of the site as the pollinators are able to move around more effectively. So I was delighted to see this post on LinkedIn from Liz Williams who works at Stanwick, demonstrating that they have taken my advice on board and begun the hard work of planting for pollinators.

My work with Stanwick was an example of the advisory and consulting services that I offer. If you’d like some advice on how to improve an area for pollinators, or for biodiversity more broadly, please do get in touch via my Contact page.

Practical methods for assessing insect pollination services provided by sites – download our new study for free

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In September 2016, along with 11 other pollinator & pollination scientists, I took part in a two-day two-day workshop held at the UNEP-World Conservation Monitoring Centre in Cambridge. The aim was to develop a range of simple, practical methods to enable the valuation of insect pollination services to agricultural crops that are provided by a nature reserves or other natural or semi-natural habitats, for TESSA – the Toolkit for Ecosystem Service Site-Based Assessments.

After a long gestation, caused not least by the COVID-19 pandemic, the paper outlining the methods that we developed has been published. It’s open-access and downloadable for free. Here’s the full reference with a link to the paper:

Ratto, F., Breeze, T. D., Cole, L. J., Garratt, M. P. D., Kleijn, D., Kunin, B., Michez, D., O’Connor, R., Ollerton, J., Paxton, R. J., Poppy, G. M., Potts, S. G., Senapathi, D., Shaw, R., Dicks, L. V., & Peh, K. S.-H. (2022) Rapid assessment of insect pollination services to inform decision-making. Conservation Biology 1–13

And here’s the Abstract:

Pollinator declines have prompted efforts to assess how land-use change affects insect pollinators and pollination services in agricultural landscapes. Yet many tools to measure insect pollination services require substantial landscape-scale data and technical expertise. In expert workshops, 3 straightforward methods (desk-based method, field survey, and empirical manipulation with exclusion experiments) for rapid insect pollination assessment at site scale were developed to provide an adaptable framework that is accessible to non-specialist with limited resources. These methods were designed for TESSA (Toolkit for Ecosystem Service Site-Based Assessment) and allow comparative assessment of pollination services at a site of conservation interest and in its most plausible alternative state (e.g., converted to agricultural land). We applied the methods at a nature reserve in the United Kingdom to estimate the value of insect pollination services provided by the reserve. The economic value of pollination services provided by the reserve ranged from US$6163 to US$11,546/year. The conversion of the reserve to arable land would provide no insect pollination services and a net annual benefit from insect-pollinated crop production of approximately $1542/year (US$24∙ha^–1∙year^–1). The methods had wide applicability and were readily adapted to different insect-pollinated crops: rape (Brassica napus) and beans (Vicia faba) crops. All methods were rapidly employed under a low budget. The relatively less robust methods that required fewer resources yielded higher estimates of annual insect pollination benefit.

Join me on Thursday for a free talk!

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Join me this Thursday at a free online talk organised by Buglife where I’ll be giving an introduction to how flowers function and the ways in which their behaviour manipulates pollinators to ensure reproduction. I’ll be covering:

What are flowers and where did they come from?
How flowers function and reward pollinators.
Some case studies from my own research on flower and pollinator behaviour.
Why is it important that we understand floral biology?

Here’s the link to register for the event: https://www.buglife.org.uk/events/to-be-a-flower-with-professor-jeff-ollerton/

I look forward to seeing you there!

The value of nature, the value of guitars

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How we, as a society, value nature, and the tension between valuing (or appreciating) nature versus appreciating (or pouring money into) human cultural activities, have been consistent themes of this blog since I started it almost a decade ago; see for example my posts “How do we value nature? Costanza, Monbiot and the clash of concepts” and “Is the angry response of (some) environmentalists in the aftermath of the Notre Dame fire reasonable?“

Putting a monetary price on nature runs counter to the personal philosophies of many conservationists, which I completely understand: I have mixed feelings too. However there’s a whole field of research devoted to it called Ecological Economics and the valuation of natural capital and ecosystem services now plays a central role in the policies and strategies of both businesses and governments: see for instance the UK Government’s recent report on “The Economics of Biodiversity: The Dasgupta Review“. And whether we like it or not, the Earth’s ecosystems and the biodiversity that they contain support our global economy in very tangible ways, a point that I emphasise in my book Pollinators & Pollination: Nature and Society. If you’re reading this with a cup of coffee in your hand, you have to consider the ecological and financial impact of the billions of wild and managed bees that support the global coffee industry.

“What’s all of this got to do with guitars?” I hear you asking. Well, music, and especially guitars, are another constant theme of the blog, including my love of the songs of Crosby, Stills, Nash and Young, and my restoration of an old acoustic guitar back in 2020.

These themes converged together in a rather unexpected way just over a week ago. It was my birthday and as a present Karin had offered to buy me a new guitar. So off we went to Copenhagen for the day. One of the city’s best guitar shops is Akustikken and there I tried out several makes and models of acoustic guitar, of varying price and quality, before finally settling on an Epiphone Texan in an aged sunburst finish (see the image below). It plays very nicely, felt right in my hands, and was moderately priced despite its solid wood construction (cheap guitars often use laminated wood).

The guitar that really caught my eye, however, was the one in the photograph above: a Martin 045-S Stephen Stills Signature Model. Now, this is a serious, serious guitar. Based on a 1930s model owned by Stills himself, it was hand made in the USA in a limited edition of 91, of which this was number 48. The woods from which it’s made are rare and exceptional, including Adirondack spruce, Madagascar rosewood, and ebony, all species about which there are significant conservation concerns (see Richard Hobbs’s great blog The Nature of Music for more on this – highly recommended for anyone interested in the interface between human culture and ecological conservation).

The price tag for this guitar? A mere160,000 Danish kroner, about £18,000 or $20,000…..

That was WAY outside of our budget! But when the staff learned that it was my birthday they kindly took the Martin out of its humidity-controlled glass case and let me play it. I was a bit overwhelmed and very nervous if I’m honest, it was easily the most expensive guitar I have ever had in my hands! Karin took a short video of me strumming a few chords which I uploaded to Twitter:

The day I played a $20,000 guitar…

On Friday, during a visit to a Copenhagen guitar store with @KarinBlak, I had the unexpected pleasure of playing a #StephenStills signature model Martin 045-S #guitar. It was…1/n#CSNY #guitarplayer pic.twitter.com/VeHAAOCuJO
— Prof. Jeff Ollerton (@JeffOllerton) February 13, 2022

Now, I’d played guitars up to around $2,000 in price that day, so a reasonable question is: did the $20,000 guitar sound ten times as good? Well, not in my hands it didn’t…. But in one sense it doesn’t matter, you’re not just paying for what it sounds like, you’re paying for the story, for the association with Stills, and the highly skilled crafting of the guitar – it is an exceptionally beautiful and fine-sounding instrument.

This brings us back to nature. We know from a lot of ecological experiments that have been conducted over the years that there’s a positive relationship between biodiversity (measured by the number of species in an ecosystem) and the way in which that ecosystem functions. So if you have more different kinds of plants in a grassland, for example, there tends to be greater carbon capture, more efficient use of water and uptake of nitrates from the soil, more resilience to events like drought and fire, and so forth. This is a strong and pervasive argument for conserving species within ecosystems: the more we have, the better the “health” of that ecosystem.

But, as with the sound of guitars, there’s probably an upper limit to this and ecosystems with ten times as many species probably do not function ten times as well. But they do function better. Having said that, this is a complex area of research with some competing ideas (and scientists) – this Wiki provides quite a good summary.

Regardless of the technical details, there’s no doubt that having more pollinators in an ecosystem, for example, increases the reproduction of a wider range of the plants that are present. Or that the presence of a greater diversity of dung beetles improves the rate of dung removal in grasslands.

But of course nature is more complicated than this. Just as a well made and high-value guitar is never going to sound good in the hands of a poor guitarist, likewise, species diversity in itself is insufficient. It is the interactions between those species that determines much of the way in which the ecosystem functions, and an ecosystem is never going to function well over the long term if it is inappropriately managed or if the processes that shape ecosystems, such as grazing by wild herbivores or natural fire regimes, are absent or have been altered.

Ecology is a hugely complex science but perhaps by exploring metaphors like this, some of that complexity can be made accessible to a wider range of people. Tell me what you think, does the metaphor work for you?

Listen to an interview with me on the Environmental Professional’s Radio podcast!

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I was recently invited to chat about careers and writing and pollinators and pollination with the folks from National Association of Environmental Professionals for their Environmental Professional’s Radio podcast. You can listen to it here:

https://www.environmentalprofessionalsradio.com/

We covered a lot of ground and it was great fun – thanks for having me!

Leonard B. Thien (1938-2021) – botanist and pollination biologist

Growing a butterfly garden? Olivia shows the way!

Earning a living as an independent academic and author: here’s what I’ve learned in my first year

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It’s just over one year since I stepped down from my full time professorship at the University of Northampton in order to work independently as a consulting scientist and author. It was a move precipitated by a number of factors, not least that after 25 years at that institution I needed some new challenges. I was starting to feel stale, jaded, and not a little burned out.

Since making the decision to leave the university (where I still hold a Visiting Professorship) Karin and I have down-sized our lives by selling our house, disposing of possessions that we didn’t need (though there’s still a lot in storage in the UK) and moving to Denmark, where we are renting a small apartment for the time being. Karin is Danish and, yes, both Brexit and the pandemic have played a role in our decision making.

A few people have asked me recently how I’m managing to earn a living as an independent academic so I thought I’d share with you my experiences so far. I’ve looked at my various sources of income over the past year and put them into four broad categories: Conservation, Research, Education and Writing. Then I worked out the proportion of my income that can be attributed to each area, keeping in mind that there’s overlap between them. This is the result:

Conservation-related activities accounted for the largest fraction, about 46% of my income. This includes direct advisory and consulting, on pollinator-related projects but also on wider, biodiversity-related topics. For example I worked with the Stanwick Lakes nature reserve in Northamptonshire, advising on how best to enhance and manage the site for pollinators.

It’s a site that I know very well but which was set up mainly because it’s important bird habitat. Seeing it from a pollinator’s perspective allowed me to make suggestions for improving the amount and timing of floral resources, opportunities for ground nesting bees, and so forth.

I’ve also been working with the Centre for Ecology and Hydrology (Wallingford) on a biodiversity strategy for the European railway network which I’ll write more about later this year when the final report is published.

Also included in the Conservation category are the many, many talks (mainly online) that I’ve done for various natural history, gardening and beekeeping groups, plus training sessions that I’ve done with ecological consultancies, estates departments, and local government. There’s a list of those available on my training and public speaking page.

Research projects funded by UK and international agencies accounted for about 32% of my income. Some of these are projects that started when I was still employed at the University of Northampton and which are paying for my time (including completing the supervision of my remaining PhD students), others are new ones. You can find a list of present and past projects on this page of my website.

I am a partner on several funding applications that are in the process of being assessed and I’ll report back when we know if they have been successful.

As well as my own research I’m also reviewing grant applications for funding organisations, advising research groups and departments on their research strategies, and working with the Turkish Journal of Botany to promote the work it publishes to a wider international audience.

Education is the third, very broad category that includes things such as external examining (both taught and research degrees), assessing staff applications for promotion, and doing the occasional online lecture. It accounted for 11% of my income, less than I might have expected given that I’ve spent over 30 years teaching in higher education, educational consulting is quite a crowded field and unless you’re a high-profile specialist, it doesn’t pay well.

Writing accounted for about 11% of my income. As well as royalties from my book Pollinators & Pollination: Nature and Society, I earned money from writing for magazines such as BBC Gardeners’ World Magazine, New Scientist, British Wildlife, and Bees & Other Pollinators Quarterly.

In addition I’ve done some advisory work for publishers, including reviewing text and making suggestions for a forthcoming children’s book about bees and other pollinators, and some paid manuscript editing.

At the moment the balance of my work feels about right; I’ll never stop being a scientist so working on research projects is, and always will be, an important part of my life. I wish that it was possible to earn more from writing, but outside of the best-seller lists it’s difficult for authors to earn a decent living. However I’m working on my next book at the moment, as is Karin whose Essential Companion to Talking Therapy has been well received.

Working independently in this way, and putting together what amounts to a “portfolio career”, is not for everyone. It’s hard work and there are lots of uncertainties along the way, especially with regard to month-to-month consistency of one’s income. However a career as a university academic has prepared me for this in ways which I’m only just beginning to discover. Aside from the obvious subject expertise, familiarity with literature searching, and confidence when giving talks, the uncertainties associated with the high proportion of unsuccessful funding applications and navigating the (often contradictory) requirements of peer reviews has been extremely valuable experience. And of course I’ve established a large and diverse network of colleagues with whom I can collaborate and go to for advice. The diversity of paid work with which I’m engaged, plus the pro bono activities such as peer reviewing for journals, ensures that there’s never a dull day. I have absolutely no regrets about this latest step in my career!

If you’re interested in working with me or want to discuss any aspect of what I’ve written about, please do get in touch via my Contact page.

Anchorage: trees rooted in rock

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Towards the end of our stay in Glastonbury, Karin and I took an omega-shaped circular walk that looped over the famous Tor, through the town, and back to our cottage. At one point the road we walked passed through a cutting in the Jurassic sandstone called Wick Hollow. Several very large oak and beech trees had anchored themselves into this stone, their roots finding cracks in the rock and no doubt widening them over time as they grew. The trees were spectacular and I took a few shots with my phone, though these really don’t do them justice.

The shade and structure created by the trees allowed a diversity of ferns, mosses, lichens and seed plants to grow. I’m always amazed by the power and adaptability of plants, even large trees, to find a foothold in the unlikeliest of places and by doing so, create microclimates that allow other species to flourish. Life supports life.

A healthy Christmas and a biodiverse New Year to all of my blog readers!

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On Sunday, following almost a week of form-filling, covid-testing and passport-stamping, Karin and I flew back to the UK to see friends and spend time with our kids. We’ve rented a large cottage in Glastonbury for the duration and the above image is taken from the back garden.

I hope that all of my blog readers have a healthy and happy Christmas, and that the New Year is both more prosperous and more biodiverse for you.

After being in rural Denmark for five months, Britain feels very congested and busy. All going to plan, we’ll be back walking the beaches of Odsherred and enjoying the scenery. See you in 2022!