EUROPEAN BLACKBIRD 81 



and other marauders, and in gardens or near habitations cats are a 

 serious menace. Where fruit is grown man must also be reckoned 

 among its enemies. 



A list of parasites recorded from blackbirds is given by Niethammer 

 (1937). 



Fall and winter.— It must be confessed that although hundreds of 

 ornithologists see blackbirds daily the life of the species during the 

 fall has not yet been studied in the intensive fashion required before 

 it will be possible to speak with the precision desirable on a number 

 of points relating to this period. There is reason to believe that among 

 resident blackbirds the old pairs maintain their association at least 

 to some extent outside the breeding season, but how far this associ- 

 ation is constant and regular is a matter of some uncertainty. There 

 is evidence that females, or some of them, in fall and winter show a 

 marked attachment to particular places and during this period of 

 the year may show a stronger territorial sense than the males, driving 

 off intruders of both sexes with considerable determination (Morely, 

 1937). Again, it has been stated, probably on good grounds, as has 

 already been noticed, that the formation of new pairs takes place, or 

 may do so, as early as October and November, but details are un- 

 fortunately lacking. Lack (1941) has noticed a definite pair as 

 early as December 25, but their earlier history is not known. What 

 is certain is that from early winter onward highly interesting, but in 

 some ways puzzling, activities of a communal kind take place. As 

 they continue into early spring they might also have been treated in 

 the section devoted to that season, but since they begin in winter they 

 will be dealt with here. These communal displays, involving much 

 chasing and posturing between males at fixed assembly places on 

 open ground, seem to be of erratic occurrence and very varying 

 intensity. Attention was first drawn to them by Miss Averil Morley, 

 already quoted, but the most spectacular type of performance, which 

 is evidently rare, has been described by H. Lambert Lack (1941): 



At first four, later six cock Blackbirds were congregated on a small area of the 

 lawn: one, sometimes two, females were seen feeding some twenty or more yards 

 away from the group. Only the males took part in the display. With wings 

 drooping and slightly extended so that their tips were visible, with tail spread and 

 depressed almost to the ground, head, neck and beak fully extended and the neck 

 feathers fluffed out, one bird would rush rapidly at another and chase it, or run 

 round and round it at a distance of apout 15 inches. Sometimes two birds would 

 circle round each other or round a third bird, or all three would be running in 

 circles. Or again two birds would run straight side by side and some twelve to 

 fifteen inches apart for a distance of three or foui yards, then switch round and 

 run back again; often two birds in a similar fashion would chase a third, one on 

 each side of it. On rare occasions these chasings ended in a brief aerial combat, 

 two birds flying up at each other to a height of two or three feet in the air and 

 apparently attacking with beak, claws and wings. The fights lasted but a second 



