Following on from last month’s mention of mistle thrushes and their association with mistletoe, while in Cambridgeshire at Christmas I was interested to see mistletoe growing abundantly on roadside ornamental apple trees in a very suburban setting. What particularly intrigued me was that several of the globes of greenery had established themselves on the slender trunks only a foot or two above the ground – with nowhere to perch, this would be an impossible position for any bird to try wiping its sticky, seed-laden beak. It seems another dispersal mechanism must be at work, but what? However sticky the contents of the berries may be, it seems highly unlikely that a falling fruit could fasten itself, limpet-like to the bark just before reaching the ground. Mice are quite arboreal and so could be responsible for bringing the fruits down towards the ground, then wiping their gooey chops on the trunk, or perhaps squirrels have acquired a taste for mistletoe. As is so often the case, we cannot completely discount the possibility of human agency; someone with a keen interest in botany could conceivably have gone round the housing estate rubbing the seeds into bark crevices, but they would need considerable patience as it takes a couple of years for the tiniest of shoots, little more than a green pimple, to appear. The other slight mystery is why mistletoe doesn’t occur in east Kent; I have found it in Chilham, Boughton and Garlinge Green, but never in Blean Woods, Canterbury or anywhere further east, although I do know of a plant that has become established in Tyler Hill due to human intervention.
Winter can be rather bleak in the wood, so the sighting of a flock of forty redpolls on 20th December was a real treat. In the first half of the 20th century the range of this elegant little finch appears to have fluctuated, but between about 1960 and 1990 numbers increased, largely due to the wealth of young conifer plantations developing in lowland England, and it was during this period that redpolls enjoyed a purple patch in Kent, with concentrations in Lyminge Forest, the Blean, and many areas in the west of the county. At that time several pairs bred on the reserve each year and, particularly during spring and autumn passage, flocks of 50 or more were frequent. Easily the best year was 1990-91, when up to 340 were present all winter, a bonus being three Arctic redpolls mixed in with them. Unhappily, during the 1990s numbers declined markedly and it ceased to breed, mirroring the trend in Kent, where it is now an extremely rare nester. Nationally, it has disappeared from many areas from the south right up into Scotland but, interestingly, it has become commoner throughout Ireland. Understandably, the sight of forty birds last month was therefore heart-warming, even though I don’t suppose that this signifies a revival of the species’ fortunes.
I’ve written occasionally about the increasing number of ravens recorded overflying the wood. My latest observation was of a bird cruising majestically overhead, drawing attention to itself with guttural “cronk” calls. It flew straight over another raven that was perched in a tree, uttering calls that, while definitely raven-like, were different to the typical note. We are abysmally ignorant about the meaning of bird calls, but recent research does at least suggest that their “language” is more complex than previously imagined, and that different calls can, for example, indicate the type and proximity of a predator, whether it is flying over or perched. It therefore seems possible that this grounded raven was imparting some specific information to the bird that was flying over. As someone who would love to see ravens nesting in Blean Woods, I like to think that the resting bird was telling the other one that this looked to be a great breeding site.
Mistletoe growing on an apple tree
Thanks, it's always good to hear what's happening in the Blean Woods. A few years ago there were suggestions in botanical circles that mistletoe was getting rarer and people should push the berries into the bark of fruit trees especially. And perhaps botanists are used to having to be patient!
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