felled timber, I have not unfrequently disturbed a Nightjar, and on such
occasions, when flying away startled, its flight so much resembles that
of a Hawk that I have twice seen a keeper shoot one, exclaiming, “There
goes a Hawk!” I was not a little surprised one day at finding one of
these birds in the middle of a turnip-field. We had marked down some
birds at the far end, and the dogs were drawing cautiously on when one
of them flushed a Nightjar, which my friend immediately shot—in mistake,
as he afterwards said, for a Woodcock.
Notwithstanding what has been said to the contrary, the Nightjar,
Night-hawk, Fern Owl, or Goatsucker, as it is variously called in
different parts of the country, is one of the most inoffensive birds
imaginable. By farmers it is accused of robbing cows and goats of their
milk, and by keepers it is remorselessly shot as “vermin;” but by both
classes its character is much maligned. Its food is purely
insectivorous, and it is as incapable of sucking milk as it is of
carrying off and preying upon young game birds. The mistake in the
former case must have arisen in this way. The habits of the bird are
crepuscular. It is seldom seen in broad daylight unless disturbed, but
as soon as twilight supervenes and moths and dor-beetles begin to be
upon the wing, it comes forth from its noonday retreat and is
exceedingly busy and active in the pursuit of these and other insects.
Montagu says he has observed as many as eight or ten on the wing
together in the dusk of the evening, skimming over the surface of the
ground in all directions, like Swallows in pursuit of insects. Cattle,
as they graze in the evening, disturb numerous moths and flies, and the
Nightjar, unalarmed by the animals, to whose presence it becomes
accustomed, dashes boldly down to seize a moth which is hovering round
their feet, or a fly which has settled upon the udder. Being detected in
this act in the twilight by unobservant persons, the story has gone
forth that the Goatsucker steals the milk.
From the keepers point of view it is a Night-_hawk_ in the worst sense
of the word, a hawk that under cover of the night flits noiselessly but
rapidly by and carries off the unsuspecting chick. But here again the
observer has been misled by appearances, associating the pointed wings
and long tail with the idea of a hawk, entirely overlooking the small
slender claws and mandibles, which are quite unequal to the task of
holding and cutting up live and resisting feathered prey, and entirely
also overlooking the fact that at the time the Nightjar is abroad, the
young pheasants and partridges are safely brooded under their respective
mothers.
Attentive observation of its habits, and examination of numerous
specimens after death, have revealed the real nature of its food, which
consists of moths, especially _Hepialus humuli_,[93] which from its
white colour is readily seen by the bird, fernchafers and dor-beetles.
Macgillivray says: “The substances which I have found in its stomach
were remains of coleopterous insects of many species, some of them very
large, as _Geotrupes stercorarius_, moths of great size also, and
occasionally larvæ. I have seen the inner surface slightly bristled with
the hairs of caterpillars, as in the Cuckoo.” He adds, “as no fragments
of the hard parts of these insects ever occur in the intestine, it
follows that the refuse is ejected by the mouth.” From its habit of
capturing dor-beetles, the bird in some parts of the country is known as
the Dor-hawk. Wordsworth has referred to it by this name in the lines—
“The busy Dor-hawk chases the white moth
With burring note.”
Elsewhere it is called the Eve-jar, and Churn-owl. The latter name is
bestowed by Gilbert White in his “Naturalist’s Summer Evening Walk”:—
“While o’er the cliff the awaken’d Churn-owl hung,
Through the still gloom protracts his chattering song.”
In his 37th Letter to Pennant, the same author refers to it as “the
_Caprimulgus_, or Fern-owl,” and gives an agreeable account of its
movements as observed by himself.
Amongst other things he says:—“But the circumstance that pleased me most
was, that I saw it distinctly more than once put out its short leg while
on the wing, and by a bend of the head deliver somewhat into its mouth.
If it takes any part of its prey with its foot, as I have now the
greatest reason to suppose, it does these chafers. I no longer wonder at
the use of its middle toe, which is curiously furnished with a serrated
claw.”
Yarrell has figured the foot, in a vignette to his work on British
Birds, in order to show this peculiarity of structure, the use of which
has puzzled so many.
The correctness of the view expressed by Gilbert White and confirmed by
other authors,[94] has been disputed on the ground that many other
birds, as Herons, Gannets, and, I may add, Coursers, have a pectinated
claw upon the middle toe, and yet do not take insects upon the wing, or
even seize their prey with their feet.
It has been ingeniously suggested that perhaps the serrated claw may be
used for brushing away the broken wings and other fragments of
struggling insects which doubtless adhere occasionally to the
basirostral bristles with which the mouth of this bird is furnished.
This is very possible; at the same time it may be observed that Hawks,
Parrots, and other birds habitually cleanse the bill and sides of the
gape with their feet, and yet have no pectination of the middle claw.
A theory advanced by Mr. Sterland,[95] and endorsed by Mr. Robert
Gray,[96] is that since the Nightjar sits _lengthwise_ and not
_crosswise_ upon a bough, the serrated claw gives a secure foothold,
which in so unusual a position could not be obtained by grasping. But to
this theory the objection above made also applies, namely, that many
birds, such as Coursers and Thick-knees, have serrated middle claws and
yet are never seen to perch.
Some naturalists, and amongst others Bishop Stanley, have surmised that
by means of its peculiarly-formed toes, the Nightjar is enabled to carry
off its eggs, if disturbed, and place them in a securer spot, but should
any such necessity arise, one would think that its large and capacious
mouth, as in the case of the Cuckoo, would form the best and safest
means of conveyance.
In the young Nightjar at first the peculiarity in question is not
observable, and Macgillivray remarked that in a fully-fledged young bird
shot early in September, the middle claw had only half the number of
serrations which are usually discernible in the adult. He says:—“All
birds whose middle claw is serrated have that claw elongated, and
furnished with a very thin edge. It therefore appears that the serration
is produced by the splitting of the edge of the claw after the bird has
used it, but whether in consequence of pressure caused by standing or
grasping can only be conjectured.” I have detected some confirmation of
this in the case of the common Thick-knee, or Stone Curlew, _Œdicnemus
crepitans_, in some specimens of which I have remarked a very distinct
serration of the middle claw, in others only the barest indication of it
(the edge of the claw being very thin and elongated); in others again no
trace of it.
The objections, however, which have been taken to the suggested use of
the pectinated claw in the Nightjar, do not invalidate the statements
which have been made by Gilbert White and other observers of the bird’s
movements and habits, for the homologous structure which is found to
exist in certain species in no way related to each other, may well be
designed for very different functions.
I do not find in the works of either Macgillivray or Yarrell any mention
made of the peculiar viscous saliva which is secreted by this bird, and
which reminds one of what is observable in the case of the Wryneck and
the different species of Woodpecker. It no doubt answers the same
purpose, namely, to secure more easily the struggling insects upon which
its existence depends.
[Illustration: CUCKOO]
THE CUCKOO.
(_Cuculus canorus._)
From numerous observations made by competent naturalists in different
localities, it appears that the usual time of arrival of the Cuckoo in
this country is between the 20th and 27th of April, and the average date
of its appearance may be said to be the 23rd of that month, St. George’s
Day. In no instance, so far as I am aware, has the bird been heard or
seen before the 6th of April. On that date in 1872 it was observed at
Torquay, but this was considered by my informant an unusually early date
at which to meet with it.
Between April and the end of August, it may be found generally
distributed throughout the British Islands, even as far north as Orkney
and Shetland. It is also a well-known visitor to the Outer Hebrides. On
the European continent it occurs throughout Scandinavia and Russia, and
is found in all the countries southward to the Mediterranean, which it
crosses in the autumn for the purpose of wintering in North Africa.
Eastward it extends through Turkey, Asia Minor, and Persia, to India,
and according to Horsfield and Temminck, visits even Java and Japan.[97]
The Cuckoo does not pair, but is polygamous. It is not unusual, soon
after their arrival, to see a couple of male birds chasing a hen. The
first eggs are seldom laid before the middle of May, or not until the
birds have been here three weeks or a month. The egg, which is about
equal in size to that of the Skylark, is very small, considering the
bulk of the bird which lays it. It is white, closely freckled over with
grey, or sometimes reddish brown, and generally has a few darker specks
at the larger end. Instead of building a nest for itself, the Cuckoo
deposits its eggs singly, and at intervals of a few days, in the nests
of a variety of other birds, and leaves them to be hatched out, and the
young reared, by the foster parents.
The nests in which the Cuckoo’s eggs are most frequently deposited are
those of the Hedge Sparrow, Meadow Pipit, Pied Wagtail, and Reed
Warbler, but according to Dr. Thienemann, a great authority on the
subject of European birds’ eggs, they have also been found in the nests
of the following very different species:—
Garden Warbler.
Blackcap.
Whitethroat.
Lesser Whitethroat.
Redstart.
Black Redstart.
Robin.
Reed Warbler.
Sedge Warbler.
Marsh Warbler.
Grasshopper Warbler.
Willow Wren.
Hedge Sparrow.
Common Wren.
Whinchat.
White Wagtail.
Grey-headed Wagtail.
Tawny Pipit.
Meadow Pipit.
Skylark.
Yellowhammer.
To this list Dr. Baldamus, from other sources, has added the
following:[98]—
Red-backed Shrike.
Barred Warbler.
Nightingale.
Icterine Warbler.
Chiff-chaff.
Great Reed Warbler.
Sedge Warbler.
Fire-crested Wren.
Tree Pipit.
Crested Lark.
Wood Lark.
Common Bunting.
Black-headed Bunting.
Greenfinch.
Linnet.
Russet Wheatear.
And lastly, in a foot-note to Mr. Dawson Rowley’s article on the
Cuckoo,[99] in which the above lists were quoted, Professor Newton has
pointed out the authority which exists for including the following, at
least occasionally, amongst the foster parents of the young Cuckoo:—
House Sparrow.
Blue-throated Warbler.
Rock Pipit.
Chaffinch.
Blackbird.
Grasshopper Warbler.[100]
Great Titmouse.
Red-throated Pipit.
Mealy Redpoll.
Bullfinch.
Jay.
Song Thrush.
Magpie.
Turtle Dove.
Wood Pigeon.
He confirms, moreover, Mr. Rowley’s remark that the Cuckoo’s egg is
occasionally found in the nest of the Brambling (_Fringilla
montifringilla_).
I have still to name four species which are not included in any of the
above lists, _viz._, the Spotted Flycatcher, Yellow Wagtail, Grey
Wagtail, and Wheatear. They were noticed by me some years ago in the
first work I ever published.[101] In the case of the Wheatear, a nest of
that bird containing three eggs of the Wheatear and one of the Cuckoo
was placed under a clod, and in such a position as strongly to favour
the opinion of some naturalists that the Cuckoo first lays her eggs and
then deposits them with her bill in the nest.
Considering the amount of attention which has been bestowed upon the
Cuckoo by naturalists in every age down to the present, one would
suppose that every fact in connection with its life-history was now
pretty generally known. Such, however, is not the case. There are still
certain points which require investigation, and which, owing chiefly to
the vagrant habits of the bird, are not easily determined.
How can it be ascertained with certainty, for example, whether the same
hen Cuckoo always lays eggs of the same colour, or whether (admitting
this to be the case) she invariably lays in the nest of the same
species—that is, in the nest of that species whose eggs most nearly
approximate in colour to her own?
And yet we must be satisfied on these points if we are to accept the
ingenious theory of Dr. Baldamus. If we understand the learned German
rightly, he states that, with a view to insure the preservation of
species which would otherwise be exposed to danger, Nature has endowed
every hen Cuckoo with the faculty of laying eggs similar in colour to
those of the species in whose nest she lays, in order that they may be
less easily detected by the foster parents, and that she only makes use
of the nest of some other species (_i.e._ of one whose eggs do _not_
resemble her own) when, at the time she is ready to lay, a nest of the
former description is not at hand. This statement, which concludes a
long and interesting article on the subject in the German ornithological
journal “Naumannia,” for 1853, has deservedly attracted much attention.
English readers were presented with an epitome of this article by Mr.
Dawson Rowley in the “Ibis” for 1865, and the Rev. A. C. Smith, after
bringing it to the notice of the Wiltshire Archæological Society in the
same year, published a literal translation of it in the “Zoologist” for
1868. More recently, an article on the subject, by Professor Newton,
appeared in “Nature” and elicited various critical remarks from Mr. H.
E. Dresser, Mr. Layard, and other ornithologists which deserve
perusal.[102]
To enter fully upon the details of this interesting subject would
require more space than can here be accorded; one can only glance
therefore at the general opinions which have been expressed in
connection with it.
If the theory of Dr. Baldamus be correct, is it possible to give a
reasonable and satisfactory explanation of it? This question has been
answered by Professor Newton in the article to which we have just
referred. He says:—“Without attributing any wonderful sagacity to the
Cuckoo, it does seem likely that the bird which once successfully
deposited her eggs in a Reed Wren’s or a Titlark’s nest, should again
seek for another Reed Wren’s, or a Titlark’s nest (as the case may be)
when she had an egg to dispose of, and that she should continue her
practice from one season to another. We know that year after year the
same migratory bird will return to the same locality, and build its nest
in almost the same spot. Though the Cuckoo be somewhat of a vagrant,
there is no improbability of her being subject to thus much regularity
of habit, and indeed such has been asserted as an observed fact. If,
then, this be so, there is every probability of her offspring inheriting
the same habit, and the daughter of a Cuckoo which always placed her egg
in a Reed Wren’s or a Titlark’s nest doing the like.” In other words,
the habit of depositing an egg in the nest of a particular species of
bird is likely to become hereditary.
This would be an excellent argument in support of the theory, were it
not for one expression, upon which the whole value of the argument seems
to me to depend. What is meant by the expression “once successfully
deposited”? Does the Cuckoo ever revisit a nest in which she has placed
an egg, and satisfy herself that her offspring is hatched and cared for?
If not (and I believe such an event is not usual, if indeed it has ever
been known to occur), then nothing has been gained by the selection of a
Reed Wren’s or Titlark’s nest (as the case may be), and the Cuckoo can
have no reason for continuing the practice of using the same kind of
nest from one season to another.
While admitting therefore the tendency which certain habits have to
become hereditary in certain animals, I feel compelled to reject the
application of this principle in the case of the Cuckoo, on the ground
that it can only hold good where the habit results in an advantage to
the species, and in the present instance we have no proof either that
there is an advantage, or, if there is, that the Cuckoo is sensible of
it.
Touching the question of similarity between eggs laid by the same bird,
Professor Newton says:—“I am in a position to maintain positively that
there is a family likeness between the eggs laid by the same bird” (not
a Cuckoo) “even at an interval of many years,” and he instances cases of
certain Golden Eagles which came under his own observation. But do we
not as frequently meet with instances in which eggs laid by the same
bird are totally different in appearance? Take the case of a bird which
lays four or five eggs in its own nest before it commences to sit upon
them—for example, the Sparrow-Hawk, Blackbird, Missel-Thrush, Carrion
Crow, Stone Curlew, or Black-headed Gull. Who has not found nests of any
or all of these in which one egg, and sometimes more, differed entirely
from the rest? And yet in each instance these were laid, as we may
presume, not only by the same hen, but by the same hen _under the same
conditions_, which can be seldom, if ever, the case with a Cuckoo.
Looking to the many instances in which eggs laid by the same bird, in
the same nest, and under the same circumstances, vary _inter se_, it is
not reasonable to suppose that eggs of the same Cuckoo deposited in
different nests, under different circumstances, and, presumably,
different conditions of the ovary, would resemble each other. On the
contrary, there is reason to expect they would be dissimilar. Further, I
can confirm the statement of Mr. Dawson Rowley, who says:[103] “I have
found two types of Cuckoo’s eggs, laid, as I am nearly sure, by the same
bird.”
It is undeniable that strong impressions upon the sense of sight,
affecting the parent during conception or an early stage of pregnancy,
may and do influence the formation of the embryo, and it has
consequently been asserted that the sight of the eggs lying in the nest
has such an influence on the hen Cuckoo, that her egg, which is ready to
be laid, assumes the colour and markings of those before her. This is
not, however, supported by facts, for the egg of a Cuckoo is frequently
found with eggs which do not in the least resemble it (_e.g._ those of
the Hedge-Sparrow); or with eggs which, from the nature of the nest,
could not have been seen by the Cuckoo (as in the case of the Redstart,
Wren, or Willow Wren); or deposited in a nest before a single egg had
been laid therein by the rightful owner. Again, two Cuckoo’s eggs of a
different colour have been found in the same nest. If both were laid by
one bird, we have a proof that the same Cuckoo does not always lay eggs
of the same colour; if laid by different birds, then the Cuckoo is not
so impressionable as has been supposed.
What really takes place, I believe, is this:—The Cuckoo lays her egg
upon the ground; the colour of the egg is variable according to the
condition of the ovary, which depends upon the age of the bird, the
nature of its food, and state of health at the time of oviposition. With
her egg in her bill, the bird then seeks a nest wherein to place it. I
am not unwilling to accept the suggestion that, being cognizant of
colour, she prefers a nest which contains eggs similar to her own, in
order that the latter may be less easily discovered by the foster
parents. At the same time the egg in question is so frequently found
amongst others which differ totally from it in colour, that I cannot
think the Cuckoo is so particular in her choice as Dr. Baldamus would
have us believe.
The manner in which “the cuckowe’s bird useth the sparrow,” “oppressing
his nest,” living upon him, and finally turning him adrift, has
furnished a theme for poets and prose writers in all ages, and has
awakened in no small degree the speculative powers of naturalists.
The story is as old as the hills, and it would probably be difficult, if
not impossible, to trace it to its origin. It was known to the ancients
that the Cuckoo leaves its eggs to be hatched by other birds, but they
mingled fact with fable, believing, or at all events asserting, that the
young Cuckoo devoured not only its foster brothers and sisters, but
ultimately its foster parents. Hence the expression which Shakespeare
put into the mouth of the Earl of Worcester to the effect that the
youngster
“Grew by our feeding to so great a bulk
That even our love durst not come near his sight
For fear of swallowing.”—_Henry IV._ act v. sc. 1.
But though so time-worn is the tale as to be very generally believed, it
is singular how few writers have attempted to show a foundation for it
from their own observations. So scattered, indeed, is the evidence on
the subject, that many naturalists of the present day still hesitate to
believe the story, pronouncing the alleged feat of strength on the part
of the young Cuckoo to be “a physical impossibility.”
Although my present purpose is to direct attention to the latest
observations upon this vexed question which have come to us with
authority, it will not be superfluous to glance very briefly at what had
already been advanced in support of the statement referred to.
Dr. Jenner says positively (“Phil. Trans.,” vol. lxxviii. p. 225):—“I
discovered the young Cuckoo, though so newly hatched, _in the act_ of
turning out the young Hedge-Sparrow. The little animal, with the
assistance of its rump and wings, contrived to get the bird upon its
back, and making a lodgement for its burden by elevating its elbows,
clambered backwards with it up the side of the nest till it reached the
top, where, resting for a moment, it threw off its load with a jerk, and
quite disengaged it from the nest. It remained in the situation for a
short time, feeling about with the extremities of its wings, as if to be
convinced whether the business was properly executed, and then dropped
into the nest again.”
Montagu, in the Introduction to his “Ornithological Dictionary,” states
that he took home a young Cuckoo five or six days old, when, to use his
own words: “I frequently saw it throw out a young Swallow (which was put
in for the purpose of experiment) for four or five days after. This
singular action was performed by insinuating itself under the Swallow,
and with its rump forcing it out of the nest with a sort of jerk.
Sometimes, indeed, it failed after much struggle, by reason of the
strength of the Swallow, which was nearly full feathered; but, after a
small respite from the seeming fatigue, it renewed its efforts, and
seemed continually restless till it succeeded.”
Mr. Blackwall, who published some observations on this point in the
fourth volume of the “Manchester Memoirs” (second series), says that a
nestling Cuckoo, while in his possession, turned both young birds and
eggs out of its nest, in which he had placed them for the purpose. He
further observed “that this bird, though so young, threw itself
backwards with considerable force when anything touched it
unexpectedly,” an observation subsequently confirmed by Mr. Durham Weir
in a letter to Macgillivray.[104]
Mr. Weir says a young Cuckoo was hatched with three young Titlarks on
the 6th June. “On the afternoon of the 10th two of the Titlarks were
found lying dead at the bottom of the ditch; the other one had
disappeared.” Subsequently this Cuckoo was removed, and placed in
another Titlark’s nest, nearer home, for more convenient observation. On
the following day Mr. Weir found it covered by the old Titlark “with
outstretched wings from a very heavy shower of rain * * * while her own
young ones had in the meantime been expelled by the Cuckoo, and were
lying lifeless within two inches of her nest.” Another instance is given
wherein two Cuckoos were hatched in a Titlark’s nest. “On the third or
fourth day after this the young Titlarks were found lying dead on the
ground, and the Cuckoos were in possession of the nest.” Ultimately one
of the latter, the weaker of the two, disappeared.