MOVEMENTS OF LONDON BIRDS 145 



During the late autumn and winter months 

 a few large birds occasionally appear heron, 

 mallard, widgeon, teal, &c. As a rule they 

 come and go during the dark hours. The sight 

 of water and the cries of the ornamental water- 

 fowl attract them. They are mostly irregular 

 visitors, and cannot very well be included in 

 the list of London birds. 



The case of the black-headed gull is different, 

 as this species may now be classed with the 

 regular visitors, and not merely to the outlying 

 spaces, like the fieldfare, but to the central 

 parks of the metropolis, where, like the wood- 

 pigeon, he looks to man for food. 



The black-headed gull has always been a 

 winter visitor in small numbers to the lower 

 reaches of the Thames, coming up the river as 

 far as London Bridge. In severe winters more 

 birds come ; thus, in the winter of 1887-8 they 

 appeared in great numbers, and ranged as high 

 up as Putney. The late Mr. Tristram- Valentine, 

 in describing this visitation, wrote: 'It is seldom, 

 indeed, that these birds appeared in such 

 numbers in the Thames above London Bridge 

 as they have done lately, and their appearance 

 has, from its rarity, caused a corresponding 



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