Tag Archives: Science

Carol Klein’s Plant Odysseys starts 29th July (and I put in an appearance in episode 1)

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Back in June last year I talked about taking part in a day of filming with Carol Klein for her new four-part series, made with Oxford Scientific Films, called Plant Odysseys.  It’s an exploration of horticultural biodiversity, each episode focused on a particular group of plants.

The first episode, devoted to roses, is broadcast this Monday 29th July at 7pm on BBC2, and I’m looking forward to seeing what the production team did with our footage from Chester.  The name may be misspelled in the publicity material but it’ll still be me….

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Garden pollinators for PAW no. 7 – Tree bumblebee (Bombus hypnorum)

Bombus hypnorum

For my final post for Pollinator Awareness Week I’ve chosen another bumblebee, one with a fascinating history and ecology. The Tree bumblebee (Bombus hypnorum) is a relatively new arrival on our shores.  It was first discovered near Southampton by Dave Goulson in 2001; since then has spread out through the country, as far north (currently) as central Scotland, and has recently been recorded from Ireland.  It arrived in Northamptonshire in 2006. The Bees, Wasps and Ants Recording Society (BWARS) has been tracking its spread through a recording scheme: it’s very distinctive being the only one of our 25 bumblebees to have a ginger thorax, black abdomen and white tail.

All the evidence suggests that this was a natural range expansion for the species rather than a deliberate or accidental introduction by people.  It’s what species do, they move around and change their distribution over timescales of decades to hundreds of years (there are lots of bird examples of this, including the Collared dove in the UK).  There’s no suggestion that this was due to climate change, however: Bombus hypnorum has long been present in colder parts of Europe and Scandinavia.

That said, there is probably a human influence to its spread as the species is closely associated with houses and gardens, often nesting in bird boxes or roof spaces (we had one in our roof for three years running).  The natural nesting habit for this bee is tree holes (hence the common name) which is why they are usually found in cavities above the ground.  However, like the Buff-tailed bumblebee, they can also be found in compost heaps, as a recent posting on the Bees Knees Facebook group showed (if you’re not a member of that group I can recommend it as it’s full of friendly, practical gardening advice for those interested in how their garden can be beautiful, productive and wildlife-friendly).

Although the Tree bumblebee will take nectar and pollen from an assortment of garden plants it seems to be particularly associated with members of the rose family (Rosaceae) and is a frequent pollinator of rosaceous soft fruit such as raspberries and blackberries.  I tried and failed yesterday to photograph the bee on our raspberries, so here’s a photograph of the outcome of that pollination.

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The Tree bumblebee is rapidly becoming one of the commonest garden bumblebees.  Is this likely to cause problems for our other bumblebees, by out-competing them for nectar and pollen, or even nesting sites?  It’s too early to tell but I’d be surprised if it does.

Bombus hypnorum March 2010

Phew!  That’s it!  It’s been a bit of marathon preparing these posts on top of writing a large grant application and a thousand other jobs, but it’s been a lot of fun.  Thanks to everyone who has viewed my posts For Pollinator Awareness Week and commented on them, either on the site or on Facebook.  Hopefully they have raised a broader awareness of our amazing native pollinators.

Garden pollinators for PAW no. 6 – Buff-tailed bumblebee (Bombus terrestris)

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It would be impossible to write a series of blog posts about garden pollinators for Pollinator Awareness Week without considering the bumblebees (genus Bombus) and I intend to devote the last two posts to that group of bees.  The bumblebees are arguably the UK’s most important pollinators of both wild and crop plants, certainly later in the season when colony numbers have increased. Earlier in the season it’s the solitary bees such as the Orange-tailed mining bee that are predominant.

Although common and widespread in gardens, the Buff-tailed bumblebee (Bombus terrestris) belongs to a group of bees in which the workers are rather variable in appearance and can be very difficult to distinguish from those in the Bombus lucorum group, which includes two other species (B. cryptarum and B. magnus).

This is a truly social species with an annual nest comprising workers and a queen.  Nests are founded by queens that have mated the previous year and hibernated.  They usually choose old rodent nests in which to begin their colonies, which is why they are sometimes found in garden compost bins.  An interesting question that I’ve not seen answered is whether the queens actively displace mice or voles from such nests: does anyone know?  This association between bumblebees and mice led Charles Darwin and Thomas Huxley into some speculation as to the role of spinsters in the British Empire.

In my garden the Buff-tailed bumblebee pollinates a range of crops including strawberries, squashes, courgettes, blackberries, runner beans, french beans, tomatoes, and raspberries.  As the photo above shows they also visit the flowers of passion fruit, where they seem to be more effective than the smaller honey bees and solitary bees.

Buff atil on Lambs ear cropped July 2015 P1120289 copy

Garden pollinators for PAW no. 5 – Orange-tailed mining bee (Andrena haemorrhoa)

Bee on apple blossom 2 - 1st May 2015

The Orange-tailed mining bee (Andrena haemorrhoa) is also referred to as the Early mining bee due to its habit of emerging from over-wintered nests as early in the year as March.  In truth, however, many Andrena species put in an early appearance, making them important pollinators of orchard fruit such as apples, which you can see from the photograph above, taken in my urban garden earlier this year.  So “Orange-tailed” is a more descriptive name.

Thanks to the Orange-tailed mining bee and other early bees, this unnamed apple variety (which Karin and I rescued from the bargain area of a local garden centre) has gone on to produce a heavy crop of eating apples (see below). There’s considerable interest in the role of wild bees such as these as pollinators of fruit in commercial orchards, not just in Europe but in the USA too, where other Andrena spp. also pollinate apples.

The epithet “Mining bees” refers to the fact that these solitary species of the genus Andrena usually make their nests in soil, excavating deep tunnels in which to construct individual cells.  It’s another generalist, taking pollen and nectar from a wide variety of garden and wild flowers.  Dandelions are particularly important early in the year – so don’t over-manage your lawn and allow some to flower!

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Garden pollinators for PAW no. 4 – Gatekeeper butterfly (Pyronia tithonus)

Gatekeeper 3 - summer 2014

For my fourth contribution to Pollinator Awareness Week I’m going to highlight the Gatekeeper (Pyronia tithonus), a butterfly that I featured on this blog last year.  As I noted in that post, it’s fairly rare to have Gatekeepers in an urban garden which indicates that the shrubs and hedges grown by myself and my neighbours are providing the right microclimate for the adults.  In addition the overgrown lawns of some adjacent gardens give opportunities for egg laying as the caterpillars are grass feeders.

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Adult butterflies are very well camouflaged when resting with their wings folded. They take nectar from a range of plants in my garden but particularly love the dark, heavily scented infloresences of the buddleia variety pictured here.  They also visit the wild blackberries scrambling through the hedge that separates us from next door’s garden and probably pollinate those flowers.  Although it’s often said that butterflies are poor pollinators compared to bees, due to their general un-hairiness and habit of holding themselves above the stamens and stigmas in a flower, it very much depends on the type of flower.  We have an unpublished manuscript that I hope to submit to a journal later this year showing that butterflies are actually better pollinators of one grassland plant than bumblebees.

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Garden pollinators for PAW no. 3 – Little flower bee (Anthophora bimaculata)

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There are only five Anthophora species in the UK and the Little flower bee (Anthophora bimaculata), as the name suggests, is one of the smallest.  This is a fast moving little beast and my fairly bog standard cameras (and a generally impatient personality) struggle to capture it: Steve Falk’s images do it justice better than I ever could.

Once again, as with the Patchwork leaf-cutter bee, the flowers of Lamb’s ear are a real favourite in my garden.  Also like that bee, this is a solitary species, though this is one that nests in dry, sandy soil.  I’ve not been able to locate any nests in my own patch and I wonder whether it’s nesting in a nearby garden.

Another generalist species, I’ve seen this bee visit food crops with open flowers such as blackberry and raspberry in my garden.  Despite its size it is likely to be quite a good pollinator of those fruit as it’s abundant, fast moving between flowers, and hairy, and can carry significant amounts of pollen.

Interestingly, Anthophora bimaculata was not recorded by Muzafar Sirohi during his surveys of bees in Northampton town centre, so it’s another species that we can add to that urban list.

Anthophora bimaculata 2 cropped P1120172 copy

Garden pollinators for PAW no. 2 – Marmalade hoverfly (Episyrphus balteatus)

Syrphid on lemon balm 1 cropped - 1P1020548 copyOne of the most frequently encountered of hoverfly species in urban gardens is the beautifully named Marmalade hoverfly (Episyrphus balteatus).  This insect is a “true fly” of the order Diptera that is sometimes confused with superficially similar wasps (order Hymenoptera), though (as the common name suggests) the species is translucent orange and black in colour rather than waspish yellow and black.  It also has a very flat abdomen whereas wasps are rounded, and they certainly don’t sting.

Individual insects are relatively ineffective as pollinators – they are small and not very hairy, so carry little pollen compared to bumblebees for instance.  However they can be extremely abundant and that abundance makes up for any individual ineffectiveness.  It’s a real generalist, visiting lots of different types of flowers, and in my garden they visit radishes (as I noted last year) and raspberries.

I often see individuals patrolling crops such as runner beans, not visiting the flowers but laying eggs on leaves and stems: the larvae of the Marmalade hoverfly is carnivorous and feeds on aphids, so it plays an interesting dual role of both pollinator and pest controller.  Definitely a gardener’s friend!

Syrphid on lemon balm 2 - 1P1020548

Pollinator Awareness Week – 13th – 19th July 2015

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Next week has been designated Pollinator Awareness Week (PAW) by Defra and there are events and profile-raising activities going on all over the country.

The motivation behind the PAW is (quote) “to bring attention to the essential needs of pollinators and the simple actions that we can all take to help pollinators survive and thrive”.

With that in mind, next week I intend to produce one blog post a day that highlights, with photographs, a pollinator (or group of pollinators) that I’ve found in my own urban garden in Northampton.  The purpose is to illustrate the diversity of pollinators that even a town garden can support, something about their fascinating life histories, and the different ecological requirements of these pollinators that our gardens can provide.  For some of them I’ll even discuss the garden crops that they pollinate.  First post will be on Monday.

If you, or the group you work with, are doing something for Pollinator Awareness Week feel free to share it in the comments section below.

How can an understanding of plant–pollinator interactions contribute to global food security? A new discussion paper

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A new discussion/review paper that I contributed to has just been published in the journal Current Opinion in Plant Biology.  Entitled “How can an understanding of plant–pollinator interactions contribute to global food security?” the paper was written in collaboration with Professor Beverley Glover and her PhD students Emily Bailes and Jonathan Pattrick at the University of Cambridge.

The abstract and highlights are copied below; if anyone wants a PDF of the full paper, send me an email or ask in the comments section.

Abstract:

Pollination of crops by animals is an essential part of global food production, but evidence suggests that wild pollinator populations may be declining while a number of problems are besetting managed honey bee colonies. Animal-pollinated crops grown today, bred in an environment where pollination was less likely to limit fruit set, are often suboptimal in attracting and sustaining their pollinator populations. Research into plant–pollinator interactions is often conducted in a curiosity-driven, ecological framework, but may inform breeding and biotechnological approaches to enhance pollinator attraction and crop yield. In this article we review key topics in current plant–pollinator research that have potential roles in future crop breeding for enhanced global food security.

Highlights:

  • Animals are globally, and increasingly, important for the improved yield and quality of many crops.
  • Floral traits are a promising and little explored avenue for the improvement of crop yields.
  • Work surrounding plant–pollinator interactions can inform us on the best strategies to do this.
  • Coordinating crop flowering time with key lifecycle stages of pollinators could benefit both crop yields and pollinators.

The uneasy academic and the importance of dipping outside your discipline: reflections on The Urban University conference

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It’s important for academics to occasionally move out of their disciplinary comfort zones and to interact with academics and practitioners from beyond their own silos, experiencing approaches that are alien and hearing voices that are not repeating the normative values of their own subject area.  Time spent in this way can be both stimulating and mundane, enlightening and boring, exciting and frustrating.  Above all, unpredictable.  At an ecological conference I know what I will experience; drop me into one devoted to the arts or social sciences, and anything can happen.  It’s an uneasy experience.

With that in mind I spent the end of last week attending a conference at which I was the lone scientist speaker, and indeed one of the very few people with a science background in the audience, as far as I could tell. The Urban University was sub-titled “Universities as place makers and agents of civic success in medium sized towns and cities” and was largely aimed at urban planners, architects, policy makers, and social geographers.  Not muddy boots ecologists.  However I’d offered the organisers (the University of Northampton’s Collaborative Centre for the Built Environment) a 30 minute talk about the monitoring work we’ve been doing on the bird assemblage at Northampton’s new Waterside Campus, which I discussed in an earlier post. The abstract for my talk is below, co-authored with my colleagues Janet Jackson and Duncan McCollin, plus two of our undergraduate students, Jo Underwood and Charlie Baker.

I had hoped that providing a very different perspective on the role of an urban campus, one focussed on the biodiversity it can potentially support and the ecosystem services that stem from it, might be of interest to this broad-based audience.  In the back of my mind I also thought it might be fun to reverse roles and, for 30 minutes, make them the uneasy ones.  It’s always hard to judge but I got the impression afterwards that the talk was well received and it elicited some discussion and questions.

Overall it was a stimulating couple of days and (I think) I’ve learned a lot, or at least learned more about the approaches and priorities of academics and practitioners beyond my immediate field. The talks ranged from the rather abstract to the very practical, from theoretical discussions to local activism. Particular highlights for me were:

John Goddard‘s overview of the relationship between the university and the city, and the fact that many academics don’t feel a personal link, or responsibility, to the urban centre in which they work.

Allan Cochrane discussing the unintended consequences of a university’s economic and social power, including gentrification and studentification of local residential areas.

Robin Hambleton on universities as a corrective to “placeless power”, i.e. multinational firms that can facilitate enormous social and economic change in an area despite having no geographic connection to the place.  Of course the internationalisation agenda of most UK universities means that they may themselves be in danger of wielding placeless power overseas.

Michael Edwards recounting how UCL academics and students have engaged in local activism in North London, for example fighting destructive planning applications, and sometimes positioned on the opposing side to the university itself.

Wendy Cukier on the experience of her Canadian university’s role as a “changemaker”, and the value of the Ashoka U Changemaker Campus programme, to which the University of Northampton is committed.

Cathy Smith on the medieval origins of the original University of Northampton, which was dissolved in 1265.  By happy coincidence 2015 is both the 750th anniversary of that dissolution and the 10th anniversary of the current University of Northampton’s full upgrade to university status in 2005.

The conference strongly impressed upon me the fact that academics sometimes take their institutions for granted in the sense that they don’t reflect on, or even challenge, the role of higher education within their geographical location. There may even be a danger of this becoming more pronounced as, in the rush to internationalise and chase overseas student fees, we in fact forget the physical and historical roots of our institutions.

Above all the two days I spent trying to navigate these unfamiliar waters reinforced my belief that it can be very dangerous for academics to isolate themselves within their disciplines, no matter how comforting and familiar that may be.  If the only voices that you are hearing (audibly and on the page) are the ones that are telling you stories that you already know and understand (even if you don’t agree with them) then it can be very easy to drift into a kind of disciplinary complacency in which you take the (self) importance and role of your own subject area for granted, without any external perspective on how it might be perceived by those beyond your academic boundaries.

Taking the occasional disciplinary leap could involve as little as going to a seminar in another department, or widening your reading to include areas beyond your subject.  Attending and presenting at a two day conference involves a greater commitment of time and energy, but it’s worth the effort.  It’s an approach to academia that I’ve tried to follow over the past 25 years and I’d recommend it as a way of broadening perspectives.  Sometimes it’s good to feel uneasy.

Many thanks to the organisers of The Urban University conference, particualrly Sabine Coady Schaebitz and Bob Colenutt, for their hard work in putting together such a great couple of days.  Here’s the details of my talk:

Biodiversity monitoring on urban university campuses

Jeff Ollerton, Joanne Underwood, Janet Jackson, Charles Baker & Duncan McCollin

Biodiversity, the variety of species and habitats to be found in a defined area, is a critical component of the natural world, and the ecosystem services that it provides supports modern society in economically tangible ways.  Urban campuses have long been acknowledged as supporting significant biodiversity, as evidenced by the many universities that have written biodiversity action plans.  However there has been relatively little quantitative research published on the biodiversity of British urban campuses, and how that diversity changes over time, particularly with respect to large-scale infrastructure development.  Academics and students in the Department of Environmental and Geographical Sciences have been collecting data on the biodiversity of Park and Avenue Campuses for more than 20 years, including plants, invertebrates, mammals, and birds.  This talk focuses on bird diversity as birds are an indicator group for assessing ecosystems, and are arguably the best understood group of species in the UK.  We present data on the birds that have been recorded on these campuses from 1993 to 2015, assessed in terms of their UK conservation status.  We then discuss the potential impact of the new Waterside Campus on the existing bird assemblage of the site, and present preliminary data showing how bird diversity has changed since building work began.  We end by discussing whether it is possible to maintain or even enhance bird diversity and abundance at the new campus.   The location of Waterside Campus, within the Nene Valley Nature Improvement Area and in close proximity to internationally important wetland bird sites, means that the University of Northampton has a civic duty to maintain the biodiversity of its campuses.

Note: in the end I actually didn’t include the data from Park and Avenue campuses, there wasn’t time to fit everything in!