BIRDS IN THE HIGH HALL GARDEN
All March the rooks were busy in the swaying elms, but it is these softer evenings of April, when the first young leaves are beginning to frame the finished nests, and the boisterous winds of last month no longer drown the babble of the tree-top parliament at the still hour when farm labourers are homing from the fields, that the rooks peculiarly strike their own note in the country scene. There is no good reason to confuse these curious and interesting fowl with any other of the crow family. Collectively they may be recognised by their love of fellowship, for none are more sociable than they. Individually the rook is stamped unmistakably by the bald patch on the face, where the feathers have come away round the base of the beak. The most generally accepted explanation of this disfigurement is the rook's habit of thrusting its bill deep in the earth in search of its daily food. This, on the face of it, looks like a reasonable explanation, but it should be borne in mind that not only do some individual rooks retain through life the feathers normally missing, but that several of the rook's cousins dip into Nature's larder in the same fashion without suffering any such loss. However, the featherless patch on the rook's cheeks suffices, whatever its cause, as a mark by which to recognise the bird living or dead.
Unlike its
cousin the jackdaw, which commonly nests in the cliffs, the rook is
not, perhaps, commonly associated with the immediate neighbourhood of
the sea, but a colony close to my own home in Devonshire displays
sufficiently interesting adaptation to estuarine conditions to be
worth passing mention. Just in the same way that gulls make free of
the wireworms on windswept ploughlands, so in early summer do the old
rooks come sweeping down from the elms on the hill that overlooks my
fishing ground and take their share of cockles and other muddy fare
in the bank uncovered by the falling tide. Here, in company with
gulls, turnstones, and other fowl of the foreshore, the rooks strut
importantly up and down, digging their powerful bills deep in the
ooze and occasionally bullying weaker neighbours out of their
hard-earned spoils. The rook is a villain, yet there is something
irresistible in the effrontery with which one will hop sidelong on a
gorging gull, which beats a hasty retreat before its sable rival,
leaving some half-prized shellfish to be swallowed at sight or
carried to the greedy little beaks in the tree-tops. While rooks are
far more sociable than crows, the two are often seen in company, not
always on the best of terms, but usually in a condition suggestive of
armed neutrality. An occasional crow visits my estuary at low tide,
but, though the bird would be a match for any single rook, I never
saw any fighting between them. Possibly the crow feels its loneliness
and realises that in case of trouble none of its brothers are there
to see fair play. Yet carrion crows, like herons, are among the
rook's most determined enemies, and cases of rookeries being
destroyed by both birds are on record. On the other hand, though the
heron is the far more powerful bird of the two, heronries have
likewise been scattered, and their trees appropriated, by rooks,
probably in overwhelming numbers. Of the two the heron is,
particularly in the vicinity of a preserved trout stream, the more
costly neighbour. Indeed it is the only other bird which nests in
colonies of such extent, but there is this marked difference between
herons and rooks, that the former are sociable only in the colony.
When away on its own business, the heron is among the most solitary
of birds, having no doubt, like many other fishermen, learnt the
advantage of its own company.
One of the most
remarkable habits in the rook is that of visiting the old nests in
mid-winter. Now and again, it is true, a case of actually nesting at
that season has been noticed, but the fancy for sporting round the
deserted nests is something quite different from this. I have watched
the birds at the nests on short winter days year after year, but
never yet saw any confirmation of the widely accepted view that their
object is the putting in order of their battered homes for the next
season. It seems a likely reason, but in that case the birds would
surely be seen carrying twigs for the purpose, and I never saw them
do so before January. What other attraction the empty nurseries can
have for them is a mystery, unless indeed they are sentimental enough
to like revisiting old scenes and cawing over old memories.
The proximity of
a rookery does not affect all people alike. Some who, ordinarily
dwelling in cities, suffer from lack of bird neighbours, would regard
the deliberate destruction of a rookery as an act of vandalism. A
few, as a matter of fact, actually set about establishing such a
colony where none previously existed, an ambition that may generally
be accomplished without extreme difficulty. All that is needed is to
transplant a nest or two of young rooks and lodge them in suitable
trees. The parent birds usually follow, rear the broods, and
forthwith found a settlement for future generations to return to.
Even artificial nests, with suitable supplies of food, have
succeeded, and it seems that the rook is nowhere a very difficult
neighbour to attract and establish.
Why are rooks
more sociable than ravens, and what do they gain from such
communalism? These are favourite questions with persons informed with
an intelligent passion for acquiring information, and the best
answer, without any thought of irreverence, is "God knows!"
It is most certain that we, at any rate, do not. So far from
explaining how it was that rooks came to build their nests in
company, we cannot even guess how the majority of birds came to build
nests at all, instead of remaining satisfied with the simpler plan of
laying their eggs in the ground that is still good enough for the
petrels, penguins, kingfishers, and many other kinds. Protection of
the eggs from rain, frost, and natural enemies suggests itself as the
object of the nest, but the last only would to some extent be
furthered by the gregarious habit, and even so we have no clue as to
why it should be any more necessary for rooks than for crows. To
quote, as some writers do, the numerical superiority of rooks over
ravens as evidence of the benefits of communal nesting is to ignore
the long hostility of shepherds towards the latter birds on which
centuries of persecution have told irreparably. Rooks, on the other
hand, though also regarded in some parts of these islands as
suspects, have never been harassed to the same extent; and if
anything in the nature of general warfare were to be inaugurated
against them, the gregarious habit, so far from being a protection,
would speedily and disastrously facilitate their extermination.
Another curious habit noticed in these birds is that of flying on
fine evenings to a considerable height and then swooping suddenly to
earth, often on their backs. These antics, comparable to the drumming
of snipe and roding of woodcock, are probably to be explained on the
same basis of sexual emotion.
The so-called
parliament of the rooks probably owes much of its detail to the
florid imagination of enthusiasts, always ready to exaggerate the
wonders of Nature; but it also seems to have some existence in fact,
and privileged observers have actually described the trial and
punishment of individuals that have broken the laws of the commune. I
never saw this procedure among rooks, but once watched something very
similar among the famous dogs of Constantinople, which no longer
exist.
The most
important problem however in connection with the rook is the precise
extent to which the bird is the farmer's enemy or his friend. On the
solution hangs the rook's fate in an increasingly practical age,
which may at any moment put sentiment on one side and decree for it
the fate that is already overtaking its big cousin the raven. Scotch
farmers have long turned their thumbs down and regarded rooks as food
for the gun, but in South Britain the bird's apologists have hitherto
been able to hold their own and avert catastrophe from their
favourite. The evidence is conflicting. On the one hand, it seems
undeniable that the rook eats grain and potato shoots. It also snaps
young twigs off the trees and may, like the jay and magpie, destroy
the eggs of game birds. On the other hand, particularly during the
weeks when it is feeding its nestlings, it admittedly devours
quantities of wireworms, leathergrubs, and weevils, as well as of
couch grass and other noxious weeds, while some of its favourite
dainties, such as thistles, walnuts, and acorns, will hardly be
grudged at any time. It is not an easy matter to decide; and, if the
rook is to be spared, economy must be tempered with sentiment, in
which case the evidence will perhaps be found to justify a verdict of
guilty, with a strong recommendation to mercy.
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