84 
The Natural History of British Ducks 
Achill a female has been known to follow her brood closely when driven into 
a yard where there were dogs and people.* 
Young Teal have many enemies in the first few weeks of their existence, 
and at the present day no worse one than individual Brown-headed Gulls 
that now summer in some of the best duck resorts, and in some instances 
threaten to exclude the birds of sport. I have said individual gulls, for the 
murders are, from my own observations, distinctly the work of single members 
of the colony, who, from jealousy or natural viciousness, cannot bear to see the 
young of other species passing near their own. 
It is just as much a truism to say that in the social scale of bird life some 
are good and some are bad, as is the case amongst men. For years whole 
colonies of Brown-headed Gulls, Rooks, Jackdaws, and the Owls and Kestrels 
of a district may lead a blameless life, and then there comes, from one cause 
or another (witness cannibalism in our own case), the criminal who strikes out 
into a series of thefts or murders, and for which the whole species is most 
unjustly condemned. If this one criminal and his family can be destroyed, 
well and good ; but how rarely does this happen ? As a rule he knows that he 
is doing wrong, and the very fact of his crime endows him with unusual 
cunning. He feeds his family on the proceeds of his depredations, and 
they in turn acquire a taste for these things, which is again transmitted to 
their offspring. Thus in a perfectly harmless community comes the bad set, 
which may in turn corrupt the whole, but which, in any case, will throw 
discredit on the respectable members. 
Twenty years ago the rooks of England were practically innocent of steal- 
ing eggs and young birds, although their cousins in the north regularly hunted 
the fallows for Peewits' eggs ; now there is hardly a community in the south 
of England that does not possess one or two professional thieves, and some 
even go the length of beating the hedgerows and taking eggs and young ones of 
little birds. If these expert robbers could only have been killed at the begin- 
ning it might have stopped the mischief in certain places; but how many 
estates in Britain possess keepers of sufficient observation and intelligence to 
