anterior two or three and the last. affords insertion to four groups
of short bristles,to which musclesare attached,and by meansof
which the worm progresses. The bristlesmay be made to point
in either direction, according as the worm wishesto advance or
retreat. When pointed towardthe tail, they hold the worm as it
crawls ahead; when directed ahead, they give foothold for
retrograde movement.
Now a person would suppose that the presenceof several
hundred little bristles, all pointing the • wrong way,' would inter-
fere with easy and pleasurabledeglutition; and inasmuchas a
worm, normally, crawls ahead, and not back, I expectedto seemy
Thrush swallow worms head first, when, it is to be presumed, the
bristles in question would not retard the process. As a matter of
fact the contrary method, as noted above, was followed. Once in
a while, a slnall worm was seized by the middle and doubled,or
taken by the head; but careful observation,extendingover several
days, brought out so few instances of this kind that I am convinced
it was a rule with the bird to swallow earthworms
tail first.
The fact that the worm often made someprogress in its attempt
to escapefrom the bird's mouth would indicate that the bristles
werein workingorder, despiteroughtreat•nent,andthat they were
pointed back, toward the tail of the worm. From this we must
infer, either that the bird was indifferent to the rasping of the
bristles on the walls of its throat• or that the sharpresistancethey
exhibited added spice and flavor to the writhing morsel. But, for
all that, anyexplanationis merelyconjecture,and why the Herinit
Thrush should chooseto begin its meal with the tail of its victim
remainsa curious,though not a profound,subjectfor speculation.
RECENT INVESTIGATIONS OF THE
EUROPEAN
BY'
F.
E.
FOOD OF
BIRDS.
L.
BEAL.
A PAPER
uponthe food of the Rook(Corz•lxsfrzG¾feffzts)
by Dr.
Hollrung,appearsin the SeventhAnnualReportof the Experi-
VoL
XIV]
x897
J
BE;xn,
P•odof J52uro•eatt
tlircls.
9
ment Stationat Halle.• Another paper by Mr. John Gilmour
of Fifeshire,Scotland,treats of the food of the Rook, the Wood
Pigeon(Cah•mbai)a/umbus)
and the Starling(Slurnusvu/graris).
These two papers are interestingcontributionsto the literature
concerningthe food of three rather importantbirds, but they can
only be consideredas givingglimpsesof a fieldin which much
remains
to be done.
Dr. Hollrung givesthe followingstatementof the foodfound
in x3• stomachs
of Rookskilled in April, May and June,withina
narrowlimit of territory: Larvaeof Zabrusgibb•s,48; wireworms
(Elaterid larva•), 20; grub worms, 253; May beetles,
weevils(Ot/arynchus),
x688; weevils (7•nymec•s),22; snails;
mice,x7; grainsof wheat,420; grainsof barley,47•; grainsof
oats, x9o; cherries, 22.
From theseexaminationsDr. Hollrung has arrived at the followinggeneral conclusions:
"L The Rooks exa•ninedhave proved on the whole neither
exclusively
useful nor exclusively
injurious. While 25 per cent
of the Rooks' stomachscontainedno vegetablematter, there were
only two casesin x3 x whereno ani•nalmatterwasfound.
"2. Their food consistedfor the most part (about 66 per cent)
of animal matter, suchas mice, larva• of the grain-eatingCarabid
(Zabrusg•ibbus),
grub worms( gœelolvntha
vu/4•aris),dungbeetles
(•lphodi•sspec.),and cloverweevils( Oliorynchus/•5•ustici).
The
vegetablefood was made up of wheat, oats, and barley, and
cherries.
"3' The harm done by the Rooks on the one hand wasperfectlybalanced,and even considerably
outweighedon the other
hand by the usefulservicesrendered.
"4. The Rooksfeed principallyon slowlymovinginsects."
In the investigations
•nadeby Mr. Gilmourthe stolnachs
of 336
birds were exmnined,not counting •9 that were empty. They
t Untersuchungen
fiber den Mageninhaltder Saatkriihe(Corvus
flus L.) Dr. M. !tollrung. 7ter Jahresbericht
Versuchs-station
f. Pfianzenschutzzu Halle a, S. •895,'pp. 5-26.
2 AninquiryConcerning.
theRelations
of Certain
Birdsto theAgricultural
Interest,asshownby theirDiet. JohnGilmour. 'Frans.IIighlandandAgri.
Soc. Scotland, •896.
Fifth Series, Vol. VIII,
pp. 2I-•
3.
' I0
BEAL,Foodof •E'urofiean
Birds.
[-Auk
[Jan.
were evenlydistributedthroughthe twelve.monthsof the year,
but were all killed in a restricted area.
Mr. Gilmour thinks,
however, that the results obtained would not differ greatly if they
had been collected over a larger district, as the one in question
may be consideredas fairly typical of southernScotland.
The food found in the 336 sto•nachswas classifiedunder four
heads,viz: (x) insectsand grubs,(2) roots,(3) cerealgrainsand
husks,(4)miscellaneous. Of these the third is of the greatest.
importance,both from its economicinterest and from the fact that
it is the food most often taken. Mr. Gilmour reckons his percentagesfrom the number of times that the bird has taken the
food, and from this concludesthat grain and husks constitute58
per cent of the Rook'sfood. Insectsand grubs, reckonedin the
sameway, amountto 23 per cent. It can hardly be claimedthat
this is the most accurate method of calculating the relative
amounts
of food found
in a bird's
stomach.
Birds
are fond
of
eating a great many different things, the aggregatequantity of
whichmay be small, just as humanbeingseat a little butter and
sugar at nearly every meal, but never make a whole dinner of
either. To illustrate, in an examinationof 2258 stomachsof the
Crow Blackbirdcorn amountedto 35 per cent of the foodby bulk,
but when reckoned by the number of times taken it aggregated
52 per cent.
Insects and grubs are mostlyeatenby the Rook from May to
August inclusive, but only in June and July do they alnount to
morethan any other item. As most of the insectsare saidto be
useful species,Mr. Gilmour is of the opinion that the harm done
by their destruction"can scarcely be consideredas counterbalancedby the grub consumpt." On the whole, his verdict is
againstthe Rook, for he says: "Taken altogether,the Rook has
ahnostno clailnto agricultural
regard....
Is not the broadfact
clear that grain is the stapleof staplefoodsfor Rooks? Lusting
for it as these birds do, we may rest assuredthat the Rook will
attack and prey freely upon the farmer's grain wheneverand
wherever favourableopportunity is presented; whether soft or
hard, whether sproutedor unsprouted,whether ripe or unripe,
whether in dung or on stubble-field,is of little lnoment to the
Rook." While he acknowledl}esthat much of this grain was taken
Vol.
XIV-]
x897
BEAL,
Foodof European
27irds.
1I
from dung,or consistedof scatteredkernelspicked up in stubblefields,he still considersthat it must all be countedagainst the
birds,as it showstheir tastefor grain. This is not fair. Grain so
obtained
a loss.
has no value to the farmer
and should not be reckoned
as
As a matter of fact, Mr. Gilmour's own tables show that
the Rooksdonot"attack and prey freely upon the farmer'sgrain
whenever and wherever favourable opportunity is presented."
Many stomachstaken in harvest time showno grain, and a large
proportionof them contained someinsects. It cannot be claimed
that any of them lacked opportunityto eat grain, for all were
collectedpracticallyfrom the samelocality.
•n comparingthe resultsobtained by these investigators
some
important differences are noted, and it is seen that the two have
drawn almost diametrically opposite conclusions The Rooks
examined by Dr. Hollrung contained 17 mice, an article of food
which
Mr.
Gilmour
does
not
seem
to have found
in his.
The
insects, unlike those eaten by the ScottishRooks, were mostly
noxious specieswhose destructionwas a decided benefit to the
farmer. While grain was eaten to someextent by Dr. Hollrung's
Rooks, it doesnot appear to constitute an important article of
their diet economicallyconsidered.
Mr. Gilmour assumesthat the Rooks taken in Fifeshire fairly
representthose of the whole of the Lowlands of Scotlandin their
food habits, an assumptionthat may possibly be true, but Dr.
Hollrung's investigationshowsthat no such suppositionwill hold
for extensiveareas of country. Stomach examination as well as
field observation
shows more and more that the kind of food taken
by birds is determinedby availability as well as taste;consequentlythe food of any particular specieswill vary to a certain
extent
in different
localities.
The Common Crow (Corz•ts american•ts) represents in this
country,as nearlyas may be, the economicpositionoccupiedby
the Rook in Europe, and a few points of comparison in their food
may not be without interest. The food of the Crow consistsof
about the same proportion of animal and vegetablematter as that
of the Rook.
In the first four itemsof Dr. Hollrung's list the Crow and the
Rook presenta great similarity of taste, the Zac•nosternaof this
I2
BF.AI., Foodof EurojbeanBirds.
[Auk
[Jan.
countryreplacingthe MeloIonthaof Europe. It is in the next two
items, the weevils, that the Rook shinesresplendent. An average
of over thirteen specimensof those small but very harmful beetles
in eachof the •3 • stomachsis certainly a splendid showing. It
is singular that none of these insectswere eaten by the Rooks
taken in Scotland. While many of thesebeetleswere eatenby
the Crow, they do not constituteso constantand importantan
item as in the case of the Rook.
The
Crow eats a considerable
number of Carabid beetles, most of which are of the more pre-
daceousspecies,while thoseeatenby the Rook are, for the chief
part, the larvm of Zabrus •ibbus, a very destructivegrain-eating
species. Grasshoppers,which are extensivelytaken by the Crow,
are conspicuously
absentfrom the food of the Rook.
In the varieties of vertebrates eaten, the Rook is far behind the
Crow. Only seventeenmicewere foundin the x3 • stomachstaken
in Germany,and nonein thosecollectedin Scotland.. In no case
did any stomachcontain the remainsof more than one. The
Crow, on the other hand, not only preys upon mice and other
small mammalsbut even captures young rabbits, and eats many
snakes, young turtles, salamanders,frogs, toadsand fish. The
Crow alsoeats many crayfishand other smallercrustaceans
which
do not appear in the Rook's bill of fare.
In the matter of vegetable food the Rook does not seemto
indulge in any great variety. It does,however,eat somepotatoes,
which the Crow rarely touches. The Crow eats aboutevery kind
of grain that the country produces,besidesfruit and acornsor
other mast. It appears to be far more omnivorous than the
Rook; in fact, it seemsdoubtful if there is anything eatablewhich
a Crow will not eat, while, so far as shown, the Rook is quite
exclusive.
In Mr. Gilmour'sinvestigationof the food of the Wood Pigeon
245 stomachswereexamined. They were quiteevenlydistributed
through the year, but, like the Rooks, were all taken within a
limited area. The contentsof these stomachsare arrangedin five
groups,which, taken in the order of frequency, are as follows:
(x) Cereal grains; (2) leaves; (3) other fruits and seeds; (4)
roots; (5) flowers. Cereal grains were taken to the extent of 33
per cent of the year's food, by Mr. Gilmour's methodof calcula-
Vol.
XlV]
x897
B•^•-,Foodof •uroj•ea•B•'rds.
13
tion, but as a great part of this was eaten in the monthsafter
August it would seem to an American farmer that it must be
mostly waste grain picked up in the stubble fields. Leaves were
eaten to the extentof 27• per cent and a large amount of these
were leaves of clover. While a bird that eats clover leavesmay
be potentiallyharmful,it is evidentthat the birdsmustbe wonderfully abundantin order to do the clovermuch daTnageby simply
eating the leaves. A great number might•possiblyhurt the forage
by breaking it down and sitting upon it. Besides cloverleaves,
the Pigeon also eats the leaves o• turnip and several weeds, as
well as the seedsof beans, peas, clover, turnips, weeds and some
trees. Roots and undergroundstems (mostly potatoes) are eaten
to the extent of 8• per cent. Mr. Gilmour's conclusionsare
entirely against the Pigeon. He says: "Though grain be left
entirely out of court,the Pigeonstandsutterly condemnedby the
heavy black score still standing against him for root-crop and
clover-leafdestruction." While we know nothingabout this bird
practically,we are inclinedto think that further observationand
thought will serveto render the scoreseveral shadeslighter.
Of the Starling, x75 stomachs were examined, collected in
every month,thoughbut few weretaken in July, August,October
and December. Like the Rooks and Wood Pigeons,the Starlings
were all taken within a small area of country. With regard to
the food in these stomachs,Mr. Gilmour says. "...
Starlings
are most monotonousin regard to diet. All the food-stuffsfound
in the crops and gizzards examined are conveniently grouped
thus: (x) grubs; (2) insects,etc.; (3) cerealgrains; (4) miscellaneous."
Of,thesethe first two amountto 7ø per cent of the wholefood,
and the third to 22 per cent. This grain is very properly not
reckoned as being very valuable, as the tables show that most o•
it was taken after liarvest time, so that the comparative usefulness
of the bird is made to depend upon the character o• the insect
food. Mr. Gilmour does not seem to have any very definite
method of determining comparative quantities of food, for he
says: "The/•o•
m•ch ot• each kind cannot,of course,be stated;
but the impressionwhich one gets from careful and close examin-
ation of the contentsof any large batch of Starlingsis that the
I4
BARLO%',
2VesDStff
Z2rab[ls
of Wh[le-la[led
]•[le.
[-Auk
LJan.
injurious speciesare more frequent in the birds than the useful
kinds." It is gratifying to learn this, as the Starling has been
introducedinto America,and in time maypossiblybecomenumerous enoughto be of economicimportance.
Mr. Gihnour makes the following happy summation of the
statusof the three birds whose food habits he has investigated.
"Of the Pigeonit may be said that he is an unmitigatedscoundrel; of the Rook that he is a cunningrogue; but of the Starling
we can say with truth that he is our natural friend, by habit and
by instinct."
SOME
NOTES
ON
THE
NESTING
WHITE-TAILED
BY
CHESTER
HABITS
OF
THE
KITE.
BARLOW.
THE White-tailed Kite (•/anus leucurtzs)
is perhapsas common
in certain portions of California as anywhere throughoutits
breedingrange,and it is residentin Santa Clara County,where
the genial climateand almost perennialsunshineare conducive
to an abundantfood supply. Santa Clara County lies southof
the San FranciscoBay region, and its northernboundaryis the
lower shoreof San FranciscoBay. The northern portionof the
countyconsistsof the • lowlands,'whichsupport,in many places,
a luxuriant growth of willow. Toward the ranges which surround the valley there are magnificent fields of live oaks and
whiteoaks,whichhave attainedin manyplacesa grandperfection.
Considerableof this country is given to farming, and here the
trees have been spared. Approaching the foot-hills, and all
throughthe valleyfroin SanJosesouthward,especiallyalongthe
water courses,
the sycamore
and whiteoak are mostcomlnonly
met with, and afford the •Su/eotribe many available and secure
nestingsites. Thus it will be seenthat certain portionsof Santa
Clara Countyare peculiarlyattractiveto raptorial birds as breed-