BRITISH WARBLERS
a raising of feathers, a spreading and jerking of the tail, an extension of the wings, and excited singing. This latter phase is by no means infrequent, the song at such a time being just as beautiful as under ordinary conditions, though clearly the expression of an entirely different emotion. One such commotion I will now describe, although the cause was shrouded in mystery owing to the density of the foliage and vegetation, coupled with a scarcity of light, and it must remain but an incident until fortune again favours and enables me to witness another of a similar kind. It happened in Texel, in one of the numerous osier beds that are dotted about the island. Listening at daybreak to the song of a male in a small osier bed my ear occasionally caught, coming from afar, the unmistakable notes of other males. These sounds I located in a larger plantation, but as it was then past 4 a.m. I determined to visit the place at daylight the following morning. This I did, and on arriving at about 2.30 a.m., heard violently excited singing proceeding from the throat of more than one male. At first there appeared to be three birds, but ultimately I came to the conclusion that there were only two. Making my way amongst the bushes I approached to within a few yards of first one and then the other, and found each one restlessly moving about within a small area. They fearlessly perched on the branches a few feet above my head, and by looking upward I could see the outline of their forms against the sky and make out their attitudes, which represented intense emotion of some kind. Their vocal productions were remarkable and defy description; it seemed as if their whole strength was concentrated upon the effort to produce the sounds. One listened to the true song of the species, then to perfect imitations of first one species, then another, and one saw, whilst the song was being produced, the wings partially expanded and jerked upwards, or even waved with a slow motion up and down. Both males were often within a short distance of one another, and fighting there may have been at times, but the density of the foliage and scarcity of light
32
