^°^i9^4"^^] Strong, Habits of the Herring GvlL 181 



it though not entirely hidden. Under such circumstances, food 

 is removed with slow and timid approaches followed by quick 

 retreats. Flapping pieces of paper were for over a year very dis- 

 turbing to the captive gulls, but after they had been fed daily for 

 some weeks with food placed on a sheet of paper, their fear of 

 moving paper decreased greatly. 



3. Reactions to Chemical Stimuli. — During considerable por- 

 tions of the time that I have had the captive gulls, I have conducted 

 experiments on their reactions to chemical stimuli. A preliminary 

 statement^ concerning the results of this work has already been pub- 

 lished, and I plan to publish another fuller account later. In 

 general, I may say here that I have found my captive gulls showing 

 what I interpret as a dislike for pieces of liver that had been dipped 

 in solutions of table salt or in weak acids. The following notes are 

 extracted from my records of the first experiment. On July 11, 

 1911, I placed a number of pieces of herring in a strong solution of 

 table salt in a pan just before feeding the gulls. Another pan con- 

 tained similar pieces of herring without any salt. The birds were 

 very hungry not having been fed since the previous evening. All 

 three birds showed great aversion for the salted fish. Two ate 

 of the salted food at once and the other joined them in a moment. 

 The response was immediate, one bird disgorging what it had swal- 

 lowed. Another dropped what it had taken, and the third swal- 

 lowed only one piece. All three birds ran to water in less than a 

 minute and drank heartily, though they had taken very little of the 

 solution. They did not return to the food during twenty minutes 

 that I waited. Experiments with other materials were carried on 

 after this until Sept. 6, 1911, when a 10% solution of sodium chlor- 

 ide was employed. Pieces of liver were placed in the solution. 

 The birds were exceedingly hungry and ate voraciously paying no 

 attention to the salt solution. On Sept. 23, a 20% solution of 

 common table salt was tried with pieces of liver. The birds were 

 not so hungry at this time. One went to the dish containing the 

 salt solution and picked up a piece of liver with the tip of its beak. 

 After a few minutes of cautious manipulation of the liver it was 

 taken into the bird's mouth only to be hurriedly ejected. The gull 



> strong, R. M. 1912. The Sense of Taste in Birds. Science, N. S., Vol. 

 XXXV, No. 911, June 14, p. 940. 



