MAESH WARBLER 



away from the nest of the latter bird. As usually happens, 

 the Sedge Warbler was most pugnacious and resented the 

 presence of other species, especially in the one particular 

 tree. The burden of his anger generally fell upon the Marsh 

 Warblers, and no discrimination w r as made between the sexes, 

 both male and female being frequently attacked and pursued. 

 The Marsh Warbler as a species is not of a very peaceable 

 disposition, and the result of this was that for some days at 

 least that particular corner of the osier bed was in constant 

 commotion. The Sedge W T arbler was undoubtedly more often 

 the aggressor, pursuing his opponents this way and that in 

 the territory, and judging by their frequent retreats the 

 Marsh Warblers must have been afraid of him. Yet at 

 times one or the other, or perhaps both, made some show of 

 resistance. Most of the skirmishing occurred in the special 

 w T illow, and in fact seemed to originate in the Sedge Warbler's 

 jealousy of that particular tree. Occasionally the quarrel 

 ended in the refusal of the Marsh Warbler to retire from his 

 headquarters, for spreading his tail he would scold vigorously 

 at his opponents only a few- feet away. Even after he had 

 obtained a female the Sedge Warbler still maintained his 

 pugnacious attitude, though perhaps in a lesser degree. 



The period of sexual activity no doubt varies in the case 

 of different individual pairs according to the early or late 

 arrival of the female, and possibly according to her physical 

 condition. I have not had opportunities of studying a suf- 

 ficient number of pairs to make a correct estimate of the 

 average duration of this period possible, but according to my 

 experience hitherto it would seem to be approximately eight 

 days. Still more difficult is it to state with any degree of 

 accuracy how long after her arrival the female actually com- 

 mences to construct her nest, but in some cases a commence- 

 ment is made on the following day. In attempting, however, 

 to estimate either of these periods one might easily be 

 deceived. The female is at all times more skulking in her 

 habits than the male. She creeps amongst the dense vegeta- 



41 



