Monthly Archives: December 2013

Thank the insects for Christmas (REBLOG)


It’s become a tradition (ok, only for the past two years, but a tradition has to start somewhere!) for me to post a version of this festive blog entry.  I’ve updated the stats for 2013.  Hope you enjoy it.

Christmas!  A time to relax and enjoy ourselves, to share time with family and friends, and to unwind during the cold and gloom of winter.  Whatever your faith, or lack of it, Christmas should be about taking a break and reflecting on the year that has passed.  We’re helped in that respect by the ceremonial seasonal trimmings: the Christmas tree, strings of flashing lights, baubles and tinsel.  So while you’re kissing a loved one under the mistletoe, admiring that glossy holly wreath, or tucking into your Christmas dinner, spare a thought for the insects.

What in Saint Nicholas’s name”  you are asking ”have insects got to do with Christmas?!”  Well, like the turkey, we’d be stuffed without them:  they play an essential part in providing us with the things we associate with Christmas.  If we had no flies, wasps, bees and other bugs acting as pollinators there’d be no berries on your mistletoe or your holly.  Kissing and admiring would be a less festive affair and that’s just for starters.  These insects also pollinate many of the vegetables, herbs and spices on your plate, as well as some of the forage that went to fatten your roast bird or tender joint of meat.   Not to forget much of what went into the nut roast that’s feeding the vegetarian relatives.

The economic value of insect pollination in the UK was estimated by the recent National Ecosystem Assessment to be about £430 million per year.  In fact this is a huge under valuation because the labour costs alone of paying people to hand pollinate those crops would run into billions of pounds.  This sounds far fetched but it’s already happening to fruit crops in parts of China.  The answer is to encourage wild insects, not artificially  managed honey bees, because collectively the former are far more abundant, and often more effective, as pollinators.  Their diversity is an insurance against losing any one species in the future. The NEA’s valuation is also too low because it only deals with commercial edible crops, and does not include those we grow in our gardens and allotments.  It also does not take account of ornamental crops such as mistletoe and holly, both of which are dioecious species, which is to say that individuals are either male or female, rather than hermaphrodite as are most plants.  This means that the plants cannot self pollinate and insects are absolutely vital to their reproduction and to the production of the decorative berries we so value (a holly wreath without berries is just a big spiky doughnut, in my opinion).

Whilst researching the economic value of the annual mistletoe and holly crops for this blog posting last year I had a conversation with Jonathan Briggs over at Mistletoe Matters and he told me that “the mistletoe trade in Britain is entirely unregulated and not documented in any tangible way”, and the same is true of holly.  We therefore have no idea what the economic value of these non-food crops actually is.  But some back-of-the-red-and-gold-Christmas-lunch-napkin calculations can at least give us an insight.  Auction reports for 2013  show that on average the best quality berried holly was selling for £2.50 per kg whilst equivalent quality holly without berries sold for only 80p per kg.  In other words, pollination by insects increases the value of that crop by more than 300%!   Similarly the high quality mistletoe averaged £1.20 per kg, whilst the second grade stuff was only 40p per kg.  And the best holly wreaths (presumably with berries!) were averaging £7.00 each.

These are wholesale prices, of course; retail cost to the customer is much greater.  A decent holly wreath will set you back between £15 and £30 whilst online shopping for mistletoe is in the £5 to £20 range, depending on how much you want.  The national census of 2011 shows us that there are 23.4 million households in England and Wales, plus there are 2.36 million in Scotland and 0.70 million in Northern Ireland.  Let’s round it down and say there’s 26 million households in the whole of the UK.  Let’s also be very conservative and estimate that only 5% of those households bought one holly wreath and some mistletoe at a total cost of £20.  Multiply that by the small proportion of households buying these festive crops and you arrive at a figure of about £26.5 million!  And that doesn’t include non-household use in shops, offices and businesses.  So there you have it: an industry worth a few tens of millions (at least) all being ultimately supported by insects.

With pollination, timing is everything, and Jonathan also made the point that spring flowering mistletoe and holly can be important early nectar sources for insects.  Therefore despite the poor  summer weather in 2012, that year was a good one for mistletoe berries because the pollination happened before the heavy rains began.  Despite being quite common plants, rather little research has been done on either holly or mistletoe pollination in the UK and it would make for an interesting student project.  The Landscape and Biodiversity Research Group here at the University has for many years been working to understand the ecology of plants and pollinators, and how to best conserve them.  In this blog I’ve referred a few times to some ongoing projects researching how the wider landscape is supporting pollinators in habitats such as country house gardens  (Hilary Erenler’s PhD work which she completed this year) and urban centres (ongoing PhD work by Muzafar Hussain).  There’s also the work completed a few years ago by Sam Tarrant and Lutfor Rahman on pollinator (and other) biodiversity on restored landfill sites.   Plus research that’s recently started by Kat Harrold on how whole landscapes support pollinators in the Nene Valley Nature Improvement Area. This is all part of a broader programme of research into the conservation of biodiversity in our region and beyond, including our Biodiversity Index, a contribution to the Shared Enterprise Empowering Delivery (SEED) sustainability project.

Biodiversity matters and its importance to our society is being increasingly recognised by government, business and the public. So if you make one New Year’s resolution on the 31st December, let it be that you will put away your garden bug sprays for 2014 and learn to love the insects (even wasps!) who give us so much and help to support our economy in a very real way.  It costs us nothing; all we need to give them is well managed, diverse, unpolluted habitats in which to live. Have a great Christmas everyone!

A Christmas vignette


This afternoon I booked half a day’s leave to go into Northampton town centre to pick up some final Christmas gifts.  A crowd of shoppers in Abington Street was eager to lay their hands on the freebies being distributed by that traditional Yuletide apparition, The Coca Cola holidaysarecomingholidaysarecoming Big American Truck.  As red and shiny as Rudolf’s nose, it was pedalling its cheap brand of Christmas sentimentality to a willing audience.  

Shopping completed and daylight fading fast, I headed back to the multi-storey car park, again passing the Coca Cola queues, skirting them, determined not to be sucked in.

The car park was cold and ugly, as they tend to be.  But on the second floor, level with the bare crown of a tree that emerges from an adjacent pub garden, a mother and her young son stood.  Hands full of shopping bags, they had paused to listen to a male blackbird singing as the dusk drew in.  As I passed I heard them chatting about its song: both agreed it was beautiful.

Driving out of the car park I wound down my window: it was still singing as I passed the tree.

I could give a very academic spin to this tale and talk about the cultural and spiritual ecosystem services that are provided by such birds, which nourish us in ways that no amount of corporate marketing ever could.  But I shan’t: it was a perfect Christmas vignette and a perfect contrast to the earlier soulless commerciality.  And that’s sufficient.

The strange and the familiar….. (back from) Brazil Diary 8

Monty and the collared dove - Sept 2013

The first bird I identified when I arrived in Brazil on 1st November was a feral pigeon (Columba livia) foraging around the airport; the first bee I spotted, visiting flowers around FUNCAMP, was a honey bee (Apis mellifera).  This tells you a lot about the widespread, near ubiquitous distribution of such species, which have been moved across much of the planet, accidentally and on purpose, by human activities.  For someone who is deeply interested in biodiversity, seeing these species is both humdrum and interesting.  Humdrum because they are so familiar, we see them everywhere we go, they are not exciting and exotic.  Interesting because they tell us a lot about the effects that humans have on their environment, how we are altering it by the introduction of non-native species.

Away from the large cities I saw introduced species such as these less and less frequently, such is their association with humans.  But of course there were also plenty of native Brazilian species that have become associated with human activities.  Some of these had a familiarity about them which transcended the fact that they were species I’d never see in Britain.  Black Vultures (Coragyps atratus) are the best example.  I would frequently observe them perched on lamp posts in towns, scanning for food or squabbling amongst themselves, and also spotted a huge number feeding on the refuse being piled into a landfill site.  Back home I associate this sort of behaviour with various species of gulls.  Strange and familiar.

Back in Northampton I’ve been reflecting on my month-long visit to Brazil, catching up with colleagues, telling stories that get more impressive with each iteration.  It’s been a packed couple of weeks and Brazil seems a long way away, not just geographically.

The Biodiversity Index did not win the Green Gown Award that it was short listed for, as I previously reported, but it did receive a Highly Commended citation.  Green Gown have asked us to produce a video, so a few days after I returned home, and still with a bit of my brain in Brazil, I took part in a short recording session about the Biodiversity Index, which will be released shortly.  The video is produced by Jo Burns and her company Amplitude Media.  Jo is a graduate of the University of Northampton and this is a nice example of how the University is supporting former students as they develop their careers.

At the end of last week we also got the news that the Biodiversity Index has been shortlisted for a Guardian newspaper University Award in the sustainability category.  More recognition for the work we’ve done on that project, and we are very pleased!  The result will be known early next year.

As of this week our paper on “How many plants are pollinated by animal?“, published in the journal Oikos in 2011, has notched up its 100th citation according to Web of Knowledge.  The less conservative Google Scholar puts it at 164, so the true answer will be somewhere in between.   Clearly peers think it’s a useful bit of work.  And to think it was almost rejected by Oikos, saved only by an appeal.  The idea for the paper arose when I was trying to find a solid figure in the literature for the proportion of plants that are biotically pollinated.  Lots of figures were being bandied about, but once you follow the reference chain back through the papers that cite them you find that numbers which are cited as solid facts disappear into speculation and guestimates.  Like many of the simple and obvious questions, the assumption is that we “know” the answer.  That’s no basis for science-informed policy, but I suspect that it happens all too frequently.