The PIED WAGTAIL (_Motacilla Yarrelli_) was formerly supposed to be
identical with the bird just described. Mr. Gould, who first decided that
the two species were quite distinct, thus discriminates between them, in
a communication to the _Magazine of Natural History_:--"The Pied Wagtail
of England is somewhat more robust in form than the true _Motacilla
alba_, and in its summer dress has the whole of the head, chest, and
back of a full, deep jet-black; while in the White Wagtail (_Motacilla
alba_), at the same period, the throat and part of the head alone are
of this colour, the back and the rest of the upper surface being of a
light ash-grey. In winter the two species more nearly assimilate in
their colouring; and this circumstance has doubtless been the cause of
their being hitherto considered identical, the black back of _Motacilla
Yarrelli_ being grey at this season, although never so light as in
_Motacilla alba_. An additional evidence of their being distinct (but
which has doubtless contributed to the confusion) is, that the female of
our Pied Wagtail never has the back black, as in the male; this part,
even in summer, being dark grey, in which respect it closely resembles
the other species."
"The Pied Wagtail of this country," says Mr. Yarrell, "though a very
common bird, is deservedly admired for the elegance of its form, as well
as for the activity and airy lightness exhibited in all its actions.
It is ever in motion, running with facility by a rapid succession of
steps in pursuit of its insect food, moving from place to place by short
undulating flights, uttering a cheerful chirping note while on the wing,
alighting again on the ground with a sylph-like buoyancy and a graceful
fanning motion of the tail, from which it derives its name. It frequents
the vicinity of ponds and streams, moist pastures, and the grass-plots of
pleasure-grounds; may be frequently seen wading in shallow water seeking
for various aquatic insects or their larvæ; and a portion of a letter
sent me lately by William Rayner, Esq., of Uxbridge, who keeps a variety
of birds in a large aviary near his parlour window for the pleasure of
observing their habits, seems to prove that partiality to other prey
besides aquatic insects, has some influence in the constant visits of
Wagtails to water. "I had," says that gentleman, "during the year 1837,
several Wagtails, the pied and yellow, both of which were very expert in
catching and feeding on minnows which were in a fountain in the centre
of the aviary. These birds hover over the water, and, as they skim the
surface, catch the minnow as it approaches the top of the water in the
most dexterous manner; and I was much surprised at the wariness and
cunning of some Blackbirds and Thrushes in watching the Wagtails catch
the minnows, and immediately seizing the prize for their own dinner."
The nest of our Pied Wagtail is formed of moss, dead grass, and fibrous
roots, lined with hair and a few feathers. It is sometimes placed on the
bare ground on a ditch bank, sometimes in a hole of a wall, or thatch of
an outbuilding, and it is frequently fixed in the side of a wood-stack
or hay-rick; occasionally it has been found occupying a cavity in a
peat-stack or a wall of turf sod, but always in the vicinity of water.
The eggs are four or five in number, white, speckled with ash-colour,
nine lines in length and seven lines in breadth.
Mr. Jesse, in his "Gleanings in Natural History," records an instance
of a Water Wagtail building her nest in one of the workshops of a
manufactory at Taunton:--"The room was occupied by braziers, and the
noise produced by them was loud and incessant. The nest was built near
the wheel of a lathe, which revolved within a foot of it. In this strange
situation the bird hatched four young ones; but the male not having
accustomed himself to such company, instead of feeding the nestlings
himself, as is usual, carried such food as he collected to a certain spot
on the roof, from whence it was borne by his mate to the young. It is
still more remarkable that she was perfectly familiar with the men into
whose shop she had intruded, and flew in and out of it without fear. If,
by chance, a stranger or any other of the persons employed in the same
factory entered the room, she would, if in her nest, instantly quit it,
or, if absent, would not return; the moment, however, that they were gone
she resumed her familiarity."