ECONOMIC RELATIONS OF OUR BIRDS.


170. FALCO COLUMBARIUS, LINN. PIGEON HAWK. GROUP III. CLASS b.
This spirited, swift-winged little Hawk has been described as one of the
most
destructive of its tribe. It captures birds upon the wing with little difficulty,
and is so audacious as to destroy Ptarmagan birds larger than itself. Its
sagacity
leads it to take advantage of gregarious species, and it follows all our
birds in
tfieir migrations north and south. Dr. Hoy states that those which nest near
Racine, regularly, morning and evening, visit the lake shore in quest of
Bank
Swallows which they seize with great dexterity. It appears to breed, as a
rule,
north of the United States, but Mr. Nelson mentions it as a rare summer resident
in Illinois.
Food: Small birds and mice. It often follows flocks of Blackbirds, Pigeons
and Robins -many of which become its victims (Wilson). It catches birds as
large as itself, follows gregarious species, and preys much upon mice, gophers,
and squirrels (Cooper). Destroys Robins, Bluebirds and Sparrows in great
num-
bers, and attacks the Pigeon and Dove (Samuels). Robin, Wild Pigeon, Golden-
winged Woodpecker, Yellow-billed   Cuckoo, and pursues Snipe and Teal
(Audubon). Bank Swallows (Dr. Roy). Feeds upon small birds, but is not
troublesome to farmers (Mr. Downes).
Falco Richardsonii is said to have been taken near Racine.
171. FALCO SPARVERIUS, LINN. SPARROW HAWK. GROUP II. CLASS C.
Except the Marsh Harrier, no Hawk is as abundant as this little Falcon. It
is more abundant in wooded districts than in prairie sections, and the borders
of
woodlands and fielAs with scattering trees are its favorite resorts. It is
too
small to be destructive to poultry, except when very young, but it is none
the less dangerous on this account to our most useful small birds. It captures
birds on the wing with little difficulty, is more than a match for the Brown
Thrasher, and tears open the bottle-shaped test of the Cliff Swallow to secure
the inmates. When autumn comes and our birds go south, " in their rear
rushes
the Sparrow Hawk." I have seen this species come close to-a house and
attempt
to capture one of a brood of young Robins which had recently left the nest.
At another time a Song Sparrow only escaped its pursuer by diving into a
brush
pile; and once one of these Hawks flew close over my head, bearing off a
small
bird in its talons. But its food does not consist of birds alone. Indeed,
it con-
sumes so many noxious insects, and is such an excellent mouser, that Dr.
Coues
says it is to be held a benefactor to the agriculturist, aad this view is
also enter-
tained by Dr. Cooper. My own notes, viewed with reference to the conditionsq
stated in the Introduction, do not, however, point in this direction. It
will bA
seen that it is very destructive to noxious insects, but it should be observed
that
these insects are destroyed in great numbers by many less dangerous species.
As an insect destroyer it is not, therefore, especially needed. Small birds
are
not so abundant at present as to demand the assistance of a large number
of
Birds of Prey to hold them in check; and plows, cultivators, reapers, mowers
and horse-rakes work such havoc among field-mice as to preclude their ever
be-
coming excessively abundant in regions where these implements are used. For
this reason the service which Rapacious Birds render by destroying mice in
agri-
cultural districts is not as great as it appears to be.
Food: Of seven specimens examined, two had eaten two mice; four, twenty-
five grasshoppers; three, twenty-five crickets; one, six beetles; one, five
moths;
and one, two hairy caterpillars (Arctia). One was seen to take a young Robin
from the nest and one to capture another bird not identified.


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