394 THE THRUSH FAMILY 



run together to form a continuous fusillade, ptickiptickticktick ! . . . 

 or minkminkmink ! . . . 



The extent to which the above notes are used to express alarm 

 varies considerably from individual to individual. This has struck 

 me particularly when approaching the nests of thrushes. Some, 

 when disturbed, will disappear without a sound, others utter tchuck ! 

 and ptickf others one of these notes only. The behaviour of 

 the same bird, again, will vary on different occasions. All these 

 variations occur whether the nest contains eggs or young. They 

 are possibly to be explained by the length of time a bird has 

 been sitting. If thoroughly fatigued, it has probably little heart 

 for protest. 1 



As a bird's vocabulary is very limited, it is not surprising that 

 the same note has to do service for the expression of more than one 

 emotional state. For instance the ptick! of the thrush is used not 

 only to express the more intense feelings of alarm, but it is heard 

 when the bird is fighting, and also, according to Naumann, when it 

 is in the excited condition that precedes migration. I have heard 

 the blackbird utter its mink! when courting, when watching a fight 

 between thrushes, and before roosting, when it may also be heard 

 uttering the tchuck ! and another note, weet ! of which more 

 presently. 



It is sometimes not at all easy to divine what meaning is to be 

 attached to a bird's utterances. Two examples will make this clear. 

 Beneath my sitting-room window is a small enclosed lawn. Into 

 this, early one morning in June, there came a cock blackbird. He 

 hopped all round it, pausing here and there to cast a glance upon 

 the soil. As he went, he uttered at every few steps a subdued 

 and meditative tchuck ! tchuck ! accompanied by somewhat dis- 

 dainful flicks of wing and tail. Then with a final tchuck! he 

 disappeared through the hedge. It is possible to explain these 



1 These conclusions are based on records of visits, in some cases repeated two to four times, 

 to thirteen different nests. 



