1919.] 
Haeusler.—Acclimatization of Birds. 
17 
when insect-life is at its lowest ebb, but also all through the summer, 
when insects are most plentiful, although then, of course, to a much less 
degree. They are particularly fond of seeds of an oily nature, and in 
districts where crops bearing such are raised on a large scale their depreda¬ 
tions are therefore by no means inconsiderable. When very hard pressed 
by hunger and cold, titmice have been observed drawing straws from 
cornstacks for the sake of the grain, but this is evidently a very rare 
occurrence. 
Among the hundreds of tits of different kinds which, with a host of other 
birds, gathered every winter round the specially prepared feeding-places 
in our garden in the northern part of Switzerland, where the winters are 
very severe, none ever betrayed any liking for grain, though thej were 
in other respects by no means particular in the selection of their rood. 
Neither did any of the numerous great tits, blue tits, coal-tits, and marsh- 
tits—which I kept every winter in captivity, to be liberated again in 
spring—ever do so. 
Titmice have been accused of damaging fruit-buds, but this is only 
correct in so far as they search for insects which these buds harbour. As 
these insects would destroy the buds anyhow, besides inflicting other 
damage to the tree, the action of the birds cannot reasonably be made the 
subject for complaint. 
The position is somewhat different in regard to the fruit itself. The 
tits are certainly not total abstainers in this direction, but the damage 
which they cause, chiefly among the cherry-trees, is by no means consider¬ 
able—in fact, quite insignificant when compared with the services they 
render these same trees and the havoc which other feathered visitors cause 
to the same crops. As it frequently happens in this world of ours that 
the innocent have to suffer for the guilty, so tits are often made responsible 
for the misdeeds of sparrows, blackbirds, and other marauders. 
It has also to be considered that not only with regard to fruit but in 
every other connection damage done to crops by birds or other animals is 
generally very quickly discovered and resented, while their good services 
are not as a rule as readily noticed. There is, moreover, always a tendency 
to overestimate any loss inflicted in our cultivations. We are, again, too 
often quite unreasonable in our attitude towards our low r er fellow-creatures, 
and inclined to forget that to labour exclusively for our benefit is not their 
role in the scheme of nature. 
It is also at all times a most difficult matter correctly to estimate the 
usefulness or harmfulness of any wild-living species. Only the most careful 
observation of their habits under all kinds of conditions, at different seasons, 
during different parts of the day and in different localities, and the 
examination of the contents of the alimentary organs of specimens procured 
under as varied conditions as possible—also, wherever possible, experiments 
on birds kept in captivity—can furnish reliable data on which to base a 
fair judgment. In the case of most of the titmice the results of such 
observations have so far been overwhelmingly in their favour: From a 
purely utilitarian point of view there is, therefore, no reason why these 
birds should not be placed high in the list of desirable immigrants. 
It is, nevertheless, well to consider certain possibilities. There is, of 
course, always a danger that in new surroundings, such as New Zealand 
offers to all Old World denizens, these latter may change their food habits 
to a more or less considerable extent, and do so to the detriment of our 
farming and fruitgrowing interests. In the case of the titmice it may be 
taken for granted that with their large families, and with so few natural 
2—Science. 
