Each year I’ve always added at least one Christmas-themed biodiversity post to the blog, for example: Thank the insects for Christmas, A Christmas vignette, and Six Kingdoms for Christmas. That’s partly because I really like Christmas as a winter festival, with its folklore and customs. But it’s also because these are a great vehicle to demonstrate how pervasive and important is natural capital and the ecosystem services it provides to society.
This year I’ve gone one stage further and actually published some Christmassy research to back up the blog post. Now, in a new study published in the Journal of Pollination Ecology, we have shown how important insect pollinators are in determining the market value of two of the most emblematic of Christmas plants: holly (Ilex aquifolium) and mistletoe (Viscum album). Here’s the full reference with a link to the paper itself, which is open access:
Holly and mistletoe are two seasonal crops that play a culturally important role as symbols of Christmas across the world, though both also have pre-Christian pagan roots. Now for the first time the role of insect pollinators in determining the commercial value of these plants has been investigated, using sales records going back over the last eleven years from Britain’s largest annual auction of holly and mistletoe, held every year in Worcestershire.
Analysis of the sales records of Nick Champion Auctions in Tenbury Wells shows that insect pollination raises the sale price of these crops by on average two to three times. This is because holly and mistletoe with berries is more sought after than material without berries, with wholesale buyers paying higher prices at auction. These berries in turn are the result of pollination by insects such as flies and bees: both holly and mistletoe are 100% dependent on insect pollination due to their having separate male and female plants.
There is some annual variation to the prices, and in years where berries are scarce (possibly due to low insect numbers) the price difference can be four-fold.
Due to concerns about pollinator declines and food security there is huge interest in the role of bees and other insects in supporting agriculture, and how we can value that role. However we believe that this is the first study showing that insect pollinators play a large part in determining the value of culturally symbolic, non-food crops. Almost all of the economic valuations of insect pollination to agriculture have focused on food crops such as beans, apples, cocoa, coffee, and so forth. Very little is known about how the value of non-food crops (fibres, construction materials, pharmaceuticals, ornamentals, etc.) is enhanced by insect pollination. This is an area where much more research is required.
But in the mean time, where better to end than with a bit of seasonal John Clare?
The shepherd, now no more afraid,
Since custom doth the chance bestow,
Starts up to kiss the giggling maid
Beneath the branch of mistletoe
That ‘neath each cottage beam is seen,
With pearl-like berries shining gay;
The shadow still of what hath been,
Which fashion yearly fades away.
The Shepherd’s Calendar (1827)
The October issue of the Natural Areas Journal is a special one devoted to the topic of “Managing for Pollinators”. All of the papers have a North American focus but I think that they will be of general interest to anyone, anywhere in the world, who is concerned with how best to manage habitats for pollinators. 
Abstract
Prof. Jeff Ollerton - ecological scientist and author 