From
October 2017 onwards we’ve been experiencing a massive ‘irruption’. Several thousands
of usually rare Hawfinches arrived unexpectedly in the UK this winter, said to
be due to a good breeding year, followed by failure of food crop sources in
Germany and Romania, with journey possibly aided by storm Ophelia, and any return
trip possibly postponed by storm Eleanor. Some have made it as far as central Exeter,
loitering for a time around St Thomas churchyard and the pleasure grounds over
the road, and then at Exwick Cemetery.
Totally Hawsome: Exwick cemetery woodland burial area |
This
is a special bird and a special opportunity. The national breeding population
hovers around 500-1000, with fidelity to certain locations, and stronghold in south east England1. These last few months have welcomed thousands to the UK, sometimes seen in
flocks fifty or more strong, instead of the average grouping of 7-8.
Size
matters; this largest finch, with the biggest beak and head, the longest
scientific name among our UK songbirds Coccothraustes
coccothraustes, and in the largest numbers - surely something this
distinctive should be easy to spot?
Afraid
not. Hawfinches are "notoriously self-effacing" and "the most challenging
songbird to observe well"2. Generally a woodland specialist,
secreted circumspectly high in the upper canopy, fawn plumage blending in with
bare trunks, with a relatively quiet infrequent song, and flying off stealthily
at the slightest hint of disturbance, the spotter’s traditional first - and
last - view of a Hawfinch is a flash of white feathers on long dark tapering
wings either side of a short tail, in a bounding flight…. as they disappear
away out of sight over the treetops….
Chances
of good sightings of these enigmatic visitors at Exwick cemetery then seemed low. But we could increase the odds maybe with some received
knowledge and strategy: start with any woodland areas; scan the uppermost
treetops; check especially cherry trees; look out for slight movements of
silhouettes which turn out to be unusually large perching birds with short
tails; be still, watchful, patient. There were not going to be many close-up
photo opportunities.
Exwick
cemetery has lots of cherry trees as well as
numerous grand old standard trees. A green burials woodland area, the
treetops of which can be viewed from paths, seemed promising in theory. A flock of 5 Hawfinches was
reported on Saturday afternoon, on cherry trees at the top of the site.
In the
first hour we tried a few different vantage points. Movements turned out to be
long-tailed tits, chaffinches, a bullfinch, goldcrest, blackbirds and
squirrels, once a sparrowhawk darting between the trunks. There was a keen northerly wind. Looking up at the canopy and thin
glare of the low winter sun, some minutes were spent in careful intense
observation of a clump of leaves.
And then, the slightest shifting out from behind the top of a cherry trunk on to an upper bough, part of a bird shape which seemed to be playing a trick of perspective appearing larger by being closer. Except it was indeed large, deftly plucking a cherry with an enormous beak. Once glimpsed, and locked on to with the binoculars, it was unmistakable.
The characteristic bill allows monopolisation of a specialised feeding niche, on tough-coated haws, sloes, cherries especially, and beech mast, amongst other seeds. It’s possible to tackle these when your face is equipped with a pair of bolt croppers. For the Hawfinch's scientific name Coccothraustes ‘kokko’ from Greek means ‘kernel’ and ‘thrauo’ ‘I break in pieces’.
This might be it .... or not |
Nature's engineering design is much more sophisticated than bolt-croppers: 4 horny pads inside the upper and lower palates hold the seed or stone in place, while distributing bite force evenly across the massive cheek muscles – the reason for the heavy-set neck and head. The crunch of the bite force is estimated to be 1000 times the bird's own weight, exerting 50-60 g/sm (1950s experiments found that 27-43kg was needed to crack open cherry stones). It is said bird ringers' knuckles, when trying to ring Hawfinches, regularly also feel this force3.
It was fascinating to observe the bill in action, not just the strength but also the nimbleness dealing with the cherry stones. Our vigilance was rewarded with sightings of 3-4 more birds. Satisfied with the morning's venture, we went in search of a warming cup of tea, and to see how the photos came out....
Postscript: as ever, I should leave it to the professionals. Here's a pic posted on the proper Devon Birds website - for more authoritative interweb information about Devon's birds and sightings, this is the place to visit.
from Devon Birds website - Hawfinch at Haldon by J. Deakins |
References
1 Wikipedia and Birdtrack website 2017
2 Peter Lack 1986 The Atlas of Wintering Birds in Britain and
Ireland Poyser, London
3 from M Cocker and R
Mabey 2005 Birds Britannica Chatto &
Windus, London, and Jonathan Elphick 1997 / reprint 2001 The BBC Birdwatcher’s Handbook A Guide to the Birds of Britain and
Ireland BBC Worldwide Ltd
– Jonathan is speaking to Topsham Birdwatching
and Naturalist group on Friday 9 March
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