BRITISH WARBLERS
LIFE HISTORY.
The Wood Warbler reaches Worcestershire considerably later than either the Willow Warbler or the Chiff-chaff, and it is of little use searching for the bird in that county before the last week in April, or, in some seasons, the first week in May. Mr. Eagle Clarke gives April 12th as the usual date of the first arrival in England, and April 25th in Scotland, the latter date being approximately the date of the first arrivals in Worcestershire. The period of arrival is spread over some weeks, just as it is in the case of other migrants; the woods which the birds are accustomed to inhabit do not suddenly become occupied by these little travellers, but are slowly filled, first in one corner, and then in another. The females commence to arrive a week or ten days after the first males, and they too come by slow degrees, this male receiving a partner to-day, that one to-morrow, and so on for a week or perhaps a fortnight.
As its name suggests, the Wood Warbler is a true occupant of woods, and whether such woods are large or small matters but little so long as the environment is in other ways suitable. Wooded banks or hills, such as are found in many parts of Wales, seem to be a favourite breeding resort, although woods which have nothing undulatory about them are also frequented. The bird is often spoken of as being especially fond of oak and beech woods, which is true enough in its way, but it is not so much a question of the kind of tree as of the nature of the ground beneath. Thick tangled undergrowth is clearly unsuitable so far as its nesting requirements are concerned, and that, I take it, is the reason of its partiality for oak or beech woods, since the undergrowth is there generally scanty, the ground being carpeted with nothing but moss and decayed leaves. Those who read the history of the Willow Warbler may perhaps remember that this question of environment was alluded to, and some remarks added on the probable effect of the felling of timber or the destruction otherwise of a breeding station. I had an interesting experience with
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