broadly edged with white; the wing quills are barred with rufous
on the outer webs; the chin, throat, and breast are blackish, the
feathers narrowly fringed with white and the rest of the lower
parts white, or faintly fulvous-white, heavily barred with strong
bands of black.
In intermediate stage between juvenile and adult the plumage is
slaty, the feathers very narrowly edged with white; below, the
chin, throat, and upper breast are blackish, the feathers broadly
fringed with white and the remainder of the lower parts like the
adult.
Hepatic young are like the hepatic female adult but less richly
colored and more heavily banded below with blackish, especially
on the chin, throat, and breast. Some specimens of young birds in
the British Museum collection seem to be changing from a juvenile
hepatic plumage into a normal adult plumage.
The white nuchal spot is very seldom seen in the young of this
cuckoo but is occasionally present.
_Measurements._--Wing 208 to 226; tail 151 to 176; tarsus about
20 or 21; culmen 20 to 22 millimeters. The female is little, if
any, smaller than the male in Indian birds, but of Chinese birds
La Touche gives the following measurements: Male, 23 (2 examples),
wing 200 to 226; female, 22 (1 example), 190–200; culmen, male,
20–22; female, 19 millimeters.
_Colors of soft parts._--Iris yellow or “grey with brown inner
circle” (La Touche); bill dark horny green, the base of the upper,
and most of the lower, mandible yellowish horny, the gape still
more yellow; legs and feet wax-yellow to rather bright yellow.
_Food._--This also is the same in character as that of _Cuculus
canorus_, but _C. optatus_ also devours more hard-bodied insects
such as Cicadae and many small and some quite large beetles, while
it feeds rather more exclusively on food obtained near the tops of
high trees. I have never seen it feeding on the ground, nor have I
noticed it in scrub or bushes except when it was probably hunting
for a nest in which to deposit its egg.
_Behavior._--I do not think that this bird could be distinguished
from _Cuculus canorus_, except by its voice, by any field
naturalist until the bird was actually in his hand. In flight,
perching position, and general action I have been able to discern
no difference of any kind between the two birds unless it is that
when the two were seen together _optatus_ looks a smaller, slighter
bird than _canorus_ and may fly a trifle faster with quicker wing
beats.
Both sexes have the habit, as _canorus_ has, of sitting, almost
motionless, for a very long time in one position, possibly in the
case of the female while she is watching certain birds and waiting
for them to give away the site of their nest, or when she is
waiting for the precise moment at which to fly down and place her
egg in the nest of the foster parent selected to receive it.
_Voice._--The call of the male consists of four notes, two rapid,
then a pause, and then two more, all of the same cadence, sounding
like _hoo-hoo hoo-hoo_. When one is close to the bird a fifth
note can be heard preceding these, much higher pitched and far
less resounding so that at a little distance only the four notes
are heard. The call is a typical cuckoo note, and hearing it one
would expect to find that a cuckoo had uttered it. There is also a
sweet trilling note that is rarely heard, and I cannot say whether
it is uttered by one sex or both, but I suspect it to correspond
to the bubbling note uttered by the female _canorus_. Although
occasionally this cuckoo calls on moonlight nights it does not do
so with anything like the perseverance of the common cuckoo, nor is
it so incessantly vocal during the day.
_Enemies._--The same as those of the common cuckoo, but the young
do not suffer so much from exposure by falling out of nests too
small or too weak to hold them. In the case, however, of eggs
laid in holes occupied by the nests of the crowned willow warbler
the young birds have to vacate them at a very early stage or they
would be unable to do so when full grown and would be incarcerated
in them for life. As these cuckoos select ground nests so largely
in which to deposit their eggs, these and the young birds when
hatched do not suffer so greatly from the crows and magpies who
hunt the hedges and bushes, but, on the other hand, they are easier
for snakes and lizards to get at.
_Fall._--Migration from the breeding grounds in northwest India
apparently commences in the end of August and continues to the end
of September or early October. From northeast India they would seem
to migrate later by about a month, birds continuing to call up to
the beginning of August, while in 1914 an egg was taken as late
as August 20. It is a curious fact that in the continent of India
birds do not seem to move far south and have only been recorded
in winter from many places in the plains of the northwest and
Punjab and from Lucknow, Jodhpore, Fategarh, Bihar, Dibrugarh and
Cachar, in the United Provinces, Bengal, and Assam. Farther east
it migrates much farther south and has been recorded from all over
Burma to the extreme south, and from the Andamans and Nicobars,
while it also ranges throughout the Malay Peninsula and the
Austro-Malaysian islands to New Guinea and Australia. Birds found
in winter east of Burma are certainly those that breed north of
China and probably migrate, more or less, due north and south, and
I am inclined to think it is possible that birds from the Himalayas
migrate almost entirely to the east in India and then southeast
through Burma and the Malay States. Otherwise it seems incredible
that no specimens should ever be obtained, in south India or even
central India, of a migrant which in and from China wanders so very
far south in the winter months.
DISTRIBUTION
The Himalyan cuckoo is found throughout the Himalayas and central
Asia from the extreme west of India and Baluchistan, while in
central Siberia it extends from Dauria and Lake Baikal to the
extreme east of the northern Chinese mountains and, possibly,
to Japan. In China La Touche (1931) summarizes its distribution
as follows: “China generally, Szechuen, Kwangsi, Fohkien, Lower
Yangtse, Shaweishan, Shantung, Chihli (migrant).” To this he
adds, “On the whole this Cuckoo is not common in North China, and
very few have been noted by Dr. Wilder,” and, again, noting on my
distribution of the summer range he adds, “Corea and Manchuria
should probably be added.”
It certainly occurs and breeds in all the higher hills in Burma;
quite commonly in the Chin Hills and rarely to the east in the Ruby
Mines district and the Shan States.
Its appearance on the American list is due to a specimen obtained
on St. Paul Island, Pribilof Islands, Alaska, on July 4, 1890 (W.
Palmer, 1894).
CUCULUS CANORUS BAKERI Hartert
KHASIA HILLS CUCKOO
CONTRIBUTED BY EDWARD CHARLES STUART BAKER
HABITS
This most interesting race of the common European cuckoo was
given a name in 1912 by Dr. Hartert (1912), no museum possessing
sufficient material until 1911 to substantiate the differences that
both Dr. Hartert and I believed to distinguish this subspecies from
those others already accepted.
The Khasia Hills cuckoo is a race that breeds at considerably lower
elevations than do either _C. c. canorus_ or _C. c. telephonus_
and, speaking generally, haunts during the breeding season more
densely forested areas in much hotter and far more humid climates.
Thus in the Khasia Hills of Assam, where it is extraordinarily
common, it may be found in all the higher ranges at and about
Sherraponji between 3,500 and 6,500 feet frequenting forest that
is always lush and green, with luxuriant undergrowth and with an
almost impenetrable tangle of creepers, beautiful orchids, ferns,
and parasites growing on every tree. Here the rainfall averages
about 550 inches in the year, while as much as 72 inches have
fallen in 24 hours and over 700 inches in the 12 months. They are,
however, equally numerous, between 4,000 and 6,000 feet around
Shillong, where the rainfall is less than 150 inches in the year
and where, in many parts, pine woods take the place of the wet
evergreen forests.
Although on the whole this race of the cuckoo certainly frequents
denser and thicker forest than do the other forms, individuals vary
greatly in their tastes and those parasitic on pipits and other
species of birds, which breed in the open grass plains, also haunt
the same kind of country as that in which these birds breed. At
the same time even in these places they always select those that
contain a certain number of trees on which they can perch and from
which they can survey the surrounding area and watch the fosterers
to their nests. In the Khasia Hills many cuckoos are parasitic
on the common Indian and Blyth’s pipits, which are to be found
nesting on the wide stretches of open grassland above Shillong, the
former on ridges and plateaus up to some 5,500 feet and the latter
on those above that altitude. Intermediate in habits between the
evergreen forest cuckoos and the open country cuckoos there are
others that haunt the more open pine forests, especially those that
have brooks and small rivers running through them, or are broken
up by ravines in which small deciduous trees, bushes, and brambles
grow freely to the exclusion of the somber pine trees.
In Burma this cuckoo is commoner in the Ruby Mines district and in
the Southern Shan States than anywhere else. T. R. Livesey, who has
had a wonderful experience with them in the latter country, informs
me that in these districts they frequent both the open deciduous
forests as well as the open country of scrub and grass land around
towns and villages, even depositing their eggs in the nests of
birds breeding in and close to the gardens of houses occupied by
Europeans or by Shans.
After the breeding season this cuckoo may be found in almost any
kind of country that is fairly well-wooded, while in the plains of
Bengal and Lower Assam it seems to have a special liking for mango
orchards and patches of jungles in tea plantations.
_Spring._--In Assam those individuals that have migrated into
the plains and lower hills the preceding autumn return to their
breeding quarters in the end of March or early April, their numbers
increasing rapidly up to the end of that month, when their mellow
call may be heard almost continually in every direction at all
elevations between 3,500 and 6,500 feet. Exact dates of arrival are
recorded nowhere that I can trace, but I have eggs taken on April
14, odd eggs taken in the third week in April, and many after the
25th of that month.
In the Chin Hills, between Assam and the Ruby Mines district and
Shan States, most cuckoos commence breeding about the middle of
April, arriving in their breeding haunts nearly a month earlier.
Here they are common at about 4,000 feet upward and haunt much the
same kinds of country as they do in Assam, certainly breeding up
to 7,000 feet, or a little over, as eggs have been taken on Mount
Victoria and the hills above Fort White.
In the Shan States Mr. Livesey informs me that few if any birds
remain above 4,000 feet in winter, in the end of August and early
September the great majority moving into the lower hills and
adjoining plains. The first birds returning to the higher hills put
in an appearance early in March and commence to lay the last of
that month, March 27 being the earliest date on which he has taken
eggs and July 1 the latest.
The length of the breeding season is much more extended than is
that of the European cuckoo (_C. c. canorus_) or the central Asian
bird (_C. c. telephonus_), doubtless owing to the same factors
of cold, food supply, etc., that compel the more northern birds
of all families to compress their breeding arrangements into a
far shorter time than that occupied by the southern birds, for
whom temperature, food supply, and other factors are more or less
favorable almost throughout the year.
The individual cuckoo, however, is governed in her time of
egg-laying by the habits of the foster parent that she selects
to bring up her young, while all cuckoos, as well as the foster
parents, are affected more or less in their spring migration and
breeding time by the late or early arrival of the rains and the
consequent shortage or abundance of insect life. In Assam, where
the rainy season is long and the rainfall heavy, eggs may be found
in some numbers from April 20 to the middle of June and, then, in
decreasing numbers, to the end of June, after which they further
decrease in number until, after the middle of July, few will be
taken, though my latest recorded date for a cuckoo’s egg is August
24. In Burma, as already noted, birds commence laying about a month
earlier, and few eggs are found after early June.
The 1,366 eggs in my collection were taken as follows: One in March
(taken in Burma), 104 in April, 608 in May, 527 in June, 114 in
July, and 12 in August. It may, I think, be accepted that migrating
birds arrive on their breeding ground some two to three weeks
before commencing to lay and leave again about one to two months
after the deposition of their last eggs.
In Burma the peak of laying is reached in early May; in Assam not
until the end of that month.
_Courtship._--I can find nothing recorded as to the conduct of
courtship between males and females during the breeding season
and have, therefore, only my own observations to guide me. There
appears to be no true courtship, and I have no doubt that, except
in very rare instances, cuckoos do not pair, though in certain
areas, where the bird is uncommon, a male and female may possibly
mate and remain together throughout the breeding season. This is
probably the case in North Cachar, where the bird is rare, breeding
in deeper forest than I have seen anywhere else, and where I have
seldom heard more than one male calling in any one particular area
or found more than one type of egg deposited therein. In the Khasia
Hills, in which district the birds swarm in incredible numbers,
both sexes were undoubtedly promiscuous in their sexual relations.
I have personally seen a female accept the attentions of one male
and then fly off to a tree close by and accept another pursuing
male within a few minutes. On this occasion several, I think four,
males were pursuing the one female, who flew slowly from one tree
to another on a roadside. Settling on one of these she crouched on
a large bough, half lying there with both wings hanging slightly
lowered and quivering, while her head was held quite low, her
whole attitude expressing invitation. The first male, of those
following her, at once accepted this after which he settled on a
branch close by while the female flew away to a tree about 50 paces
distant followed by the other three males, one of whom was again
accepted by the female who, after the completion of the act flew
off accompanied by the remaining two males to a tree beyond my view.
Among the Khasias, certain classes of whom are very intelligent
observers, it appears to be well known that both sexes of cuckoo
exercise no discretion in their love affairs.
_Nesting._--The female cuckoo is, of course, parasitic in her
habits, and I have personally taken eggs in the nests of no less
than 103 species and subspecies of fosterer (see following list),
the very great majority of which are, however, undoubtedly abnormal
or casual only, for I feel satisfied that when the usual foster
parent has no nest available the cuckoo will eventually deposit
her egg in that of any other bird that may be convenient. Repeated
instances have come within my own experience in which a cuckoo
normally parasitic on one bird deposits one or more of a series of
eggs in a nest utterly unlike those of the usual fosterer, merely
because she has already exhausted all the nests known to her of the
latter.
LIST OF FOSTER PARENTS
eggs
_Suya crinigera_ (subspecies 6) 215
_Cisticola jundicis cursitans_ 276
_Cisticola exilis tytleri_ (generally with _C. j. c._ series) 7
_Tribura luteiventris_ 32
_Orthotomus_ (species and subspecies 2) 27
_Acanthopneuste reguloides harterti_ 9
_Megalurus palustris_ 7
Miscellaneous warblers (abnormal fosterers, 9) 25
_Anthus_ (various species and subspecies, 8) 199
_Rhodophila ferrea haringtoni_ 18
_Saxicola caprata burmanica_ 55
_Rhyacornis fuliginosus_ 25
_Enicurus_ (species 2) 25
_Petrophila (Monticola)_ (species 2) 21
Turdidae (abnormal fosterers, species 8) 15
_Cyanosylvia leucura_ 13
_Eumyias thalassina thalassina_ 63
_Niltava_ (species 3) 43
Muscicapidae (abnormal fosterers, species 12) 22
_Lanius nigriceps nigriceps_ 35
Laniidae (abnormal fosterers, species 2) 2
Troglodytidae (species 3) 21
_Mesia agentauris_ 46
_Leiothrix calipyga_ 33
Timaliidae (abnormal fosterers, species 32) 92
Other abnormal fosterers, _Passer_, _Sitta_, _Parus_, etc.
(7 species) 8
Total _Fosterers:_ Normal 23, abnormal 80 ( = 103).
Like the English cuckoo, as Chance (1922) has proved, the Khasia
Hills female cuckoo sometimes adopts a certain area of country
as its own breeding territory into which it will allow no other
female, parasitic on the same foster parent, to enter, though it
seems to have no objection to the entry of any number of males
or of another female parasitic on a different species. Thus in a
certain area close to the house in which I lived in Shillong I
found three cuckoos breeding; one depositing its eggs in the nests
of the little fantail warbler (_Cisticola juncidis cursitans_), the
second in the nests of the verditer flycatcher (_Eumyias thalassina
thalassina_), and the third in the nests of the black-headed
shrike (_Lanius nigriceps nigriceps_). On another occasion I
took eggs of three different cuckoos from nests of _Cisticola_,
_Niltava_, and _Leiothrix_ in the same strip of jungle and not 50
yards from one another. Yet another instance of shared territory
was a grass-covered hillside occupied by two female cuckoos, the
one parasitic on the same little fantail warbler and the other on
pipits (species various). Other similar instances were quite common
in this district.
My personal experience confirms what those interested in
cuckoo-work have for some time maintained in regard to cuckoos
being consistently parasitic on one selected foster parent. A good
example of this constancy is a series, collected for me by a family
of four men trained by myself in cuckoo-work in the Khasia Hills.
From 1925 to 1935 these men obtained for me no less than 132 eggs
of one cuckoo parasitic on the fantail warbler, all collected in
the same area of grass and scrub surrounded by pine forest. Of
these 132 eggs only 4 were taken from nests other than those of
the little fantail and of these 4, 3 were placed in the nests
of another little warbler (_Orthotomus sutorius patia_) and the
other in the nest of the Assam brown hill warbler (_Suya crinigera
assamica_), both, of course, in the same territory.
In addition to the above I have many series of eggs, numbering 3
to 15, from individual cuckoos, occasionally taken in two or more
consecutive years, all placed in nests of the same warbler. Again I
have other series of cuckoos’ eggs, some taken from nests of _Suya_
(various species); others from those of _Eumyias_, pipits (various
species), the silver-eared mesia (_Mesia a. argentauris_), the
Pekin robin (_Leiothrix lutea calipyga_), and other fosterers. As a
rule the cuckoo also shows equal constancy to its chosen breeding
area, returning year after year to it and leaving it only when the
supply of fosterers is exhausted or the nature of the country has
been altered by man or some other agency. Where the normal foster
parent is exceptionally common, such as are the warblers of the
genera _Cisticola_ and _Suya_, the cuckoo often has ample nests in
a compact area to act as hosts to her whole series of eggs, and we
have found as many as 18 eggs laid by the same individual within
such an area. Where, however, the fosterers such as pipits or mesia
are less numerous or are breeding in comparatively small areas,
some 4 to 10 eggs are laid in the one area and then, when the
available nests have all been made use of, the cuckoo removes to
another area, generally close by, eventually often returning to the
original one later in the season and again cuckolding other nests
of the same fosterer.
There can, I think, be no doubt that a cuckoo brought up in a nest
of a certain fosterer will deposit its own eggs in nests of the
same bird. This theory seems now to be one generally accepted,
and certainly my experience goes to confirm this, and in my own
collection I have eggs of a very definite type taken for over 30
years in the nests of the same species of fosterer in the same
district.
_Eggs._--The eggs of the Khasia Hills cuckoo are of very many and
beautiful types of color and character of markings, while the eggs
of each individual cuckoo, though varying slightly _inter se_, do
not show so great a variation as is found in the eggs of single
clutches laid by many species of Passeres or other orders.
Among the most common types of eggs are, naturally, those that
have been evolved to assimilate with the eggs of the birds most
frequently employed as foster parents. Among these may be mentioned
the following:
An egg with a white ground lightly marked, chiefly at the larger
end, with specks, spots, or small blotches of red, reddish brown,
or brown. These eggs are excellent counterparts in all but size
of the eggs of the fantail warbler, in whose tiny nest they are
usually deposited.
The next commonest type has the ground color more or less
distinctly tinged with reddish and is rather more profusely marked
with larger blotches of various shades of red-brown. These are
normally deposited in the nests of various species of _Suya_, or
brown hill warbler, the most common types of whose eggs agree well
with those of the cuckoo.
A third and common type of cuckoo’s egg has the ground color a
beautiful salmon-pink or buff-pink and has the surface freckled
with deeper reddish; in some cases so finely and thickly that the
eggs appear at first glance to be unicolored; in other cases more
or less boldly, though sparsely, covered with reddish brown and
underlying faint marks of gray or pale purple. These eggs agree
well with various types of eggs laid by the verditer flycatcher
and, even still more so, with those of the beautiful niltava
(_Niltava sundara_), while it is in the nests of these birds we
find them deposited. Cuckoos, however, that normally deposit
their eggs in the nest of these birds seem regularly also to
cuckold the large niltava (_N. grandis_) and the white-tailed chat
(_Muscisylvia notodela_), which lay the same colored eggs and make
similar cup-shaped nests of living moss, built in exactly similar
positions in holes in banks and among boulders.
Another beautiful type is bright pale blue, often immaculate but
sometimes faintly flecked with primary reddish and secondary gray
blotches. In the Khasia Hills these are almost invariably deposited
in the nests of the silver-eared _Mesia_ or the red-billed
_Leiothrix_ (_L. lutea calypga_), two species that lay exactly
the same type of egg to that of the cuckoo, though more boldly
blotched, while the two species also make similar nests, which they
place in somewhat similar positions in bushes, etc.