130



THE MISTLE THRUSH’S FEET, AN OVERLOOKED

ADAPTATION


by Derek Goodwin



Nearly everyone who has written about the habit of the Mistle Thrush

Turdus viscivorus of guarding berried trees and shrubs, especially berry¬

bearing Holly trees Ilex aquifolium and clumps of Mistletoe Viscum album ,

driving from them other berry-eating birds, especially other species of thrush

Turdus spp., have emphasised how like a Sparrowhawk Accipiter nisus it is in

the way it flies to attack them, singling out one individual and trying to come

on it suddenly round the side of the guarded Holly tree or Mistletoe clump.

The fear felt by these birds being often so great that they make no attempt

to feed from them afterwards unless they see the Mistle Thrush is being

kept away by the presence of humans. Although in hard weather, with snow

cover and all unguarded fruit already eaten, other thrushes and Waxwings

Bombycilia garrulus, when starving, form flocks and overwhelm the guarding

Mistle Thrush which can only attack one individual at a time.


See especially two excellent and well-written books, Birds and Berries

by Barbara and David Snow (1988) and the monograph The Sparrowhawk by

Ian Newton (1986). In a recent issue of Bird Watching , Cousens (2007) also

made no mention of leg and feet colour, although the colour plate p.45 clearly

showed the yellow legs and feet and black claws of the Mistle Thrush.


I phoned David Snow, a long-time friend and nearly as long an ex¬

colleague of mine and he said that, unlike me he had never seen an attacking

Mistle Thrush from in front and only a little above him unobscured by

branches. I had and it was a very memorable experience, though it occurred,

I think, in the 1970s. It was a fine and relatively mild day in late winter and

I had been walking along a track near a wood where a pair of Sparrowhawks

usually bred, when I saw what I at first thought was some Accipiter spp.

unknown to me, its bright yellow legs and black-clawed feet were stretched

down but then upwards and forwards. It was terrifying as I thought it was

going to strike my face and only when it swerved past me and round the

berry-laden Holly bush did I realise it was, in fact, a Mistle Thrush.


Consulting photographs in books later I realised that the odd-looking

breast pattern, which had made me think it was an unknown hawk, is in fact

very like that of an immature Sparrowhawk.


The only other kind of thrush I have been able to find described as having

similar coloured legs and feet is the Yellow-legged Thrush Platycichla

flavipes. As its generic name suggests, this species has a stouter bill and

wider gape than typical thrushes. The male of a pair I saw close when in

Brazil in 1972 had a bright orange bill and orange-yellow legs, I did not



