And now there’s scientific evidence that proves it.
A recent study in Australia has shown that mistletoes are essential for maintaining biodiversity in native Australian forests. One third of bird species vanished when mistletoe was absent and, since those birds were largely insectivorous species, the value of the mistletoe lies not just in berries and nesting habitat but also in the number of insects directly or indirectly supported.
The research took place over five years and involved physical removal of mistletoe in 17 sites ranging from 5 to 25 hectares. There were also 23 control sites either with undisturbed mistletoe or with a natural absence of mistletoe. For full details check out the Royal Society Proceedings or the summaries at ABC Science or in a recent Economist write-up.
This study is, of course, not about our native European mistletoe, and indeed as there are over 90 mistletoe species in Australia higher diversity is to be expected there. But our own single mistletoe species does have similarities – with a distinct assemblege of obligate insects and a handful of birds that specialise in the berries. This value is recognised in Europe and in the UK, where mistletoe’s biodiversity contribution to old orchards is often quoted. More obscure and indirect biodiversity benefits, such as those arising from the differing leaf litter etc implied in the Australian study, have not been assessed in Europe – perhaps they should be…
But any study needs careful planning and a long-term commitment. And it will be hard work – this is what Professor David Watson of Charles Sturt University (pictured) said about the mistletoe clearance work:
“it took teams of volunteers months and months to remove about 46 tonnes. It was a considerable logistical exercise. It was a royal pain in the ass.”
And, of course, his research proves it would have been better to have left it there…