METHODS OF STUDYING THE FOOD OF BIRDS 



13 



fruit-eating birds do not digest tlieir food so tlioroughly but 

 that its nature is apparent from the excreta. Wherever birds 

 roost in numbers, pellets or excreta or botli may be gathered, 

 and when analyzed will give results scarcely less valuable 

 than those obtained by dissection, with the advantage that 

 there is no sacrifice of bird life. 



A study of the food of nestlings is less diriicult and ou tlic 

 whole more satisfactory. Both the kind and llic (piaiitily 



i:i;ai)Y tu fekd. 



may be accurately determined without injuring so much as 

 a feather. 



If the nest is on or near the ground, a small neutral-rolort'd 

 tent may be set up beside it as near as you please, into which 

 you may retir(\ and, by watching the progress of atfairs 

 througli a small '' peep-hole,*' fdl your note-book with an ac- 

 count of the rations that are consumed. If on the ground the 

 nest and young may be transferred to a sunken pail for better 

 observation, as shown in the bobolink photograi)hs herewith. 

 It usually ]iapi)ens, however, that the nest is not in a i)osilion 



