The MARTIN or ROOF SWALLOW (_Chelidon urbica_) we have selected as the
type of a group, recognisable by their slightly forked tail and strong
feet, the toes of which are connected from the first joint, and, like the
tarsi, are thickly covered with feathers. This bird is five inches and
a half long, and ten and three-quarters broad; the wing measures four
inches, and the tail two and a half. Upon the back the plumage is almost
entirely of an uniform blueish black; the under side and rump are white.
The eye is dark brown, the beak black, and the bare parts of the foot
black. Both sexes are alike in colour, but the plumage of the young is
less clear in its tints than that of the adult. The Martin inhabits the
whole of Europe, and penetrates further north than the Chimney Swallow;
it is numerous in Siberia, and during its migrations visits the interior
of Africa and Southern Asia. In most respects it closely resembles the
species already described, but is somewhat less brisk and intelligent;
its flight also is not so rapid and varied as that of the Chimney
Swallow, but it frequently soars to an enormous height in pursuit of the
insects upon which it subsists. Its voice is very far inferior to that of
the rest of its family, and its cry monotonous and harsh.
In populous districts the nests of this bird are invariably constructed
upon houses, but where human habitations are scarce, the Roof Swallow
is content to make its preparations upon rocks, or any situation that
will afford it a secure shelter from the wind and rain. The nest is
very similar to that of the Chimney Swallow, but with this difference,
that it is always built against a hole, and has no external entrance;
sometimes many pairs construct their dwellings under the same eaves or
the same rock, and thus form a kind of settlement. Although usually
peaceful, during the breeding season disputes and battles are of constant
occurrence; each couple naturally endeavouring to obtain the snuggest
corner, and to oust its neighbour should the opportunity offer. The brood
consists of from four to six delicate snow-white eggs, and the nestlings
are hatched in about twelve days. The female alone broods, and is fed by
her mate only when the weather is fine; the young also frequently have
but an insufficient supply of food, owing to the difficulty of procuring
insects when the season is inclement, and thus must very often be left
behind when the flocks migrate, as they are still too weak to undergo
such great fatigue. If all goes well, the nestlings are fully fledged
in about sixteen days, but generally remain for some time longer under
the care of their parents. During this period the whole family return
at night to their nest, which they fill so completely that we have
often been inclined to wonder that the walls did not give way under the
pressure to which they were subjected. Desperate fights often ensue when
a stray bird finds its way into a wrong nest, and most courageously
do those in possession exert themselves to expel the intruder, who is
generally equally determined to remain. Far less brave is the Swallow
when brought into collision with its principal enemy, the Sparrow;
it often happens that no sooner is the Swallow's nest completed than
a male Sparrow creeps in and takes possession, keeping guard at the
door, in order to prevent the entrance of the rightful owner; under
these circumstances, the latter, not venturing to obtain admittance by
force, usually summons its companions, who together beset the impudent
intruder with loud cries and every demonstration of anger. In most cases
the Sparrow retains possession of its ill-gotten abode, but should the
Swallow be bold, a battle sometimes takes place that proves fatal to one
or other of the combatants. So constant are these attempts of the Sparrow
to obtain a home for its young, that a pair of Swallows sometimes are
deprived _twice_ in the season of the domicile they have laboriously
completed, and, should this occur, do not breed at all that year. It was
formerly imagined that the Swallow revenged itself on its foe by building
it up in the nest, but we need hardly say that this is untrue.
The Martins make their appearance in England a few days after the Chimney
Swallow (_Cecropis-Hirundo-rustica_), and on their arrival are usually
seen in warm and low situations, such being most likely to supply an
abundance of their natural food. They are equally distributed throughout
the kingdom, and are found wherever man has fixed his residence, seeming
to court his protection. They commence nidification early in May, and
build in the upper angles of windows and under the eaves of houses,
sometimes under the arches of bridges or against the face of rocks. The
nest is formed of mud completely worked and cemented, and is closed all
round except a small orifice, usually on the sheltered side, just of
sufficient size to permit the passage of the inhabitant; the interior is
well lined with a collection of straw, hay, and feathers. These birds
leave us in October; preparatory to their departure, they congregate in
great numbers on the roofs of houses.
* * * * *
The MOUNTAIN or SHORE SWALLOWS (_Cotyle_) are recognisable by their
slightly forked tail, and lax, lustreless plumage. Two species are
indigenous to Europe; a description of these will serve for the entire
group.