° 1914 J Strong, Habits of the Herring Gull. 29 



between the mandibles of the adult and the bird was pulled about 

 until the skin and flesh were cut through to the skull." 



This maltreatment of the young has also been described by 

 Dutcher and Baily ^ and it has been discussed by Herrick. I 

 found that similar treatment was administered to a juvenal gull 

 when it was placed in a cage with two juvenals two to three weeks 

 older. One gull, the youngest of the three in the cage, was par- 

 ticularly persistent and savage in its attacks so that I had to 

 remove the newcomer until its head had healed and it was better 

 able to defend itself. 



On erecting my tent at one of the Sister Islands, July 12, 1911, 

 I took a downy juvenal not more than a week old, inside with me. 

 This I released at 12: 50 p. m., and it made its way out at once. Its 

 appearance outside caused great excitement. The little gull 

 started west in the direction of the place where I had captured it. 

 On its way it went near a couple of gulls which appeared to belong 

 to a nest I had under observation. These birds started the " chal- 

 lenge cry," and others joined in the same performance. The small 

 gull approached the two adults just mentioned and was pecked on 

 the head after a minute or so. It was next given a number of sharp 

 blows which apparently did no serious damage. The little bird 

 turned at bay and when pecked most severely ran screaming with 

 mouth open, towards >its persecutors. This was followed by alter- 

 nate running and fighting, a procedure which was successful in 

 preventing further serious attacks. The bird eventually found 

 shelter under some drift wood about fifty feet away from my 

 tent. 



Herrick explains these attacks upon the young as follows: 

 "This is due to the ferocity of the guarding and fighting instincts 

 in the old birds, and to a lack of attunement in the instincts of the 

 young, in consequence of which a chick will occasionally stray from 

 its own preserve and trespass on the domain of a neighbor." Un- 

 doubtedly this covers many and perhaps most cases, but it seems 

 doubtful whether the deaths among the juvenals at Gravel Island 



> Dutcher, W. and Bally, W. L. A Contribution to the Life History of the 

 Herring Gull (Larus argentatus) In the United States. Auk, Vol. XX, 1903, 

 No. 4, pp. 417-31. Plates XXI-XXII. 



