July, 1905 
THE FUTURE PROBLEMS AND AIMS OE ORNITHOLOGY 
95 
PARENT FEEDING YOUNG BUSH-TITS 
The Future Problems and Aims of Ornithology" 
A BETTER I* ROM MR. WILI.IAM BREWSTER 
Cambridge, Mass., Feb. 19, 1905. 
Dear Mr. Fisher: 
Your questions are so comprehensive and far reaching that I cannot answer 
all of them without giving more time and thought to the matter than are at pres- 
ent at my disposal. I will say briefly, however: (1) That of the more general 
problems in ornithology not related to any one country, that concerning the inter- 
relation of bird with other animal life — and with plant life — seems to me to be best 
worth the attention of young ornithologists. By this I mean to say that what is 
called the “balance of nature” should be more closely studied. The subject is at pres- 
ent veiled in obscurity. We know for example that herons, kingfishers and loons 
eat fish; but just what fish do they eat, and upon what do these fish subsist? If 
on other animal life, what do these other animals eat? Do not the kingfishers and 
herons eat creatures other than fish? etc. 
The study of bird migration is another general problem that is not likely to 
be exhausted for many years to come. 
(2.) With reference to North American birds it is especially desirable to know 
more definitely whgre certain of them do or do not go to spend the winter. The 
summer distribution of many of them is also but imperfectly known. An especial 
a A continuation of the series of letters begun in the last issue of The Condor. Mr. Brewster has taken up sev- 
eral specific questions. The answers sufficiently indicate the nature of the questions. — F, d. 
