INCREASE OF ANIMAL LIFE 395 



these new commercial multitudes, could there, nevertheless, 

 be clearer evidenceof the influence of cultivation in increasing 

 numbers ? 



INCREASE OF GARBAGE 



In addition to the more or less "natural food with which 

 a generous culture of the fields has supplied many creatures, 

 the increase of the refuse of civilization has tended greatly 

 to the multiplication of the garbage feeders. In the days 

 before man concerned himself with health matters, the self- 

 imposed duties of scavengers undertaken by birds and 

 beasts must have saved him from many a pestilence. At one 

 time, Kites were common in the streets of London, and the 

 condition of Edinburgh and Leith in the sixteenth century 

 and earlier led to a great increase in the numbers of the 

 crow tribe Carrion Crows, Rooks, and probably Ravens 

 which, as is shown by an extract from Wedderburn's Accompt 

 Book already quoted (p. 224), were familiar objects in 

 the streets. It is also on record that "in the sixteenth 

 century, Ravens were encouraged to multiply in Berwick 

 where they were actually protected in the town on account 

 of their value as scavengers (see p. 225). As the crow tribe 

 has benefited by the garbage of the towns, the Seagulls have 

 flourished upon the offal of the fishing villages. 



No animal has multiplied so successfully on the refuse of 

 civilization as the Brown Rat. It lurks in the midclen of the 

 farmyard, it riddles the refuse dumps of country-towns and 

 villages, and it thrives by thousands in the sewers of our 

 large cities. Mr Wm Berry has recorded that the removal 

 of a refuse dump at Tayfield in Fife, rid his district of Rats, 

 which had appeared in such numbers that the repairing of 

 the damage done to field dykes, through the undermining of 

 their foundations by Rats, cost over ^200. 



Many garbage feeders amongst insects have developed 

 unwonted hordes through the ways of mankind. As early 

 as 1675 Mackaile had noticed that artificial heaps of sea- 

 weed bred large numbers of insects, probably the Two- winged 

 Flies Ccelopa frigida and Actora cestuum, and perhaps also 

 small amphipod crustaceans like the Shore-fleas (Talitrus 

 saltator and Orchestia gammarellus] to the benefit of their 

 feathered destroyers. 



