THE NIGHT CRY OF THE REDWING.
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and, besides, the noise of the gale may drown all other sounds.
Once or twice, however, I have detected beyond any doubt the
"seep" of a Redwing in a lull in the storm. On still nights the
clouds often form in strata, with clear air above and below ;
this is not always obvious in a lowland county, but is extremely
noticeable during a walk on the Pennines, when a few minutes
may be enough to carry one from a thick mist to a clear blue
sky. I have an idea, not yet definitely a belief, that flying Red-
wings fly either below or above this stratum of cloud. It will
be understood that a ten-mile walk after dark, over lonely
moorland roads rising to 1,600 feet above sea level, is not always
possible or desirable ; one has to depend on chance observa-
tions or observations made on the 1,000 feet contour within
a mile or so of the house.
Another strange fact is that the "seep" alone should be
heard at night. During the daytime the "Chup" and the
"seep" are used indifferently, but I cannot remember ever
hearing the former note after dark. Occasionally, in Lancashire,
many years ago, and in Essex during later years, I have made
special visits to the favourite thickets where Redwings roost in
large companies. I have watched the birds trooping in for the
night, and have seen them settle to rest, remaining for a long
time in the hope of detecting some movement in connection
with their nocturnal rambles. An hour after all is still, the
chance of hearing the aerial note is no greater than it would
be if one stood on a wide moorland, or in Trafalgar Square ;
these visits have never added anything to my knowledge.
When do Redwings begin to fly ? I hear them first when it
is just too late to detect the passing birds ; and I have often
remarked that had they been half an hour earlier, I should have
seen the birds against the sky; and, as I have often had the
opportunity of noting, these flights continue all night, and cease
when the day begins to lighten.
What can be the explanation ? The only one that I can
think of is that these flights are, so to speak, a form of song—a
letting-off of superfluous energy. The Moorhen "sings" this
way, careering around over town and country from March to
July; but I do not think we can hope to hear Moorhens beyond
a three-miles radius from their ordinary haunts. The Snipe,
also, utters a "song" largely instrumental—much of the energy