MARSH WARBLER
prevented my following their movements. As the light increased the excitement dwindled, and both birds gradually lapsed into silence. I then made a search for a female, but without success. That the one male possessed a territory, and made his headquarters in a tall alder tree I proved to my own satisfaction, but on the following morning one male only was singing, there being no trace of the second, and the excitement of the first one was by no means so intense as on the previous day. Owing to this episode occurring at the end of a brief stay in the island, I was unable to complete the record of the sexual life of the two males, and in the absence of such a record it will be well, perhaps, to refrain from further speculation. One point, however, may be mentioned in connection therewith. The plantation was only a short distance away from another of a similar kind in which there were also two occupied territories. The owner of one of these was paired, the nest built, and two eggs laid, but the other male is the one which calls for attention. He had been in the territory a week at least, but not continuously, sometimes he was there, sometimes undoubtedly absent; but his presence always seemed to be a source of irritation to the other male, and generally terminated in a conflict. After one such encounter I noticed that he deserted his territory altogether for a time. Now the ground that he occupied did not appear to be altogether suitable for breeding purposes. It embraced a corner only of the plantation, and that corner was covered for the most part with tall trees, beneath which there was little in the way of dense vegetation, small bushes, or withies, in which a nest could be suitably placed. It is possible, therefore, that this bird was the second male referred to as being in the aforesaid plantation, and that being in an unsettled condition on account of not possessing a suitable territory, he was roaming backwards and forwards between the two plantations. An instance of a similar kind has recently come under my notice in the case of another species, the male apparently possessing two territories, in each of which he spent part of his time.
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