690 THE BIRDS OF YORKSHIRE. 



whole field was cleared by the Kittiwakes of " twitch," which 

 had been worked out of the land, between Saturday and 

 Monday. The question formerly used to be asked, " Has 

 thou been up at Cliff ; is Kitts carrying ? " by men who 

 wished to know if it was worth while going out to the slaughter. 

 Excursionists and gunners from inland towns were also guilty 

 of wanton cruelty in shooting the poor birds while nesting, 

 the young being left to perish on the cliffs, and there was a 

 danger of their extermination, until the passing of the Sea- 

 birds Preservation Act of 1869 put an end to the butchery. 

 Now the numbers of nesting birds are gradually increasing, 

 although, where one nest may at present be seen, there used 

 formerly to be half-a-dozen, and the eggs were then sold 

 at the rate of four or five for a penny. 



The Kittiwake arrives at the breeding quarters at Bempton 

 and Speeton at dates varying from the I2th of March, which 

 is the earliest I have note of, up to the third week of April. 

 The method of climbing for Seabirds' eggs, described under 

 the heading of the Guillemot, is applicable to this species 

 also. The first clutches consist of three in number, and are 

 laid about the last week in May ; if these are taken the bird 

 lays again, but, as a rule, produces two only as the second 

 clutch. W. Wilkinson, the Bempton cliff-climber, has 

 frequently taken eight eggs from one nest : first three, second 

 and third clutches of two each, and for the last laying one 

 only ; he has very rarely known nine laid by one bird, and, 

 in the instances where this has occurred, the second set has 

 consisted of three. The intervals between the laying of the 

 clutches is practically the same as in the case of the Guillemot, 

 about fourteen days, or, if the eggs are incubated, the time 

 is extended to eighteen or twenty days. Occasionally varieties 

 are found of a pale green colour, entirely spotless ; a clutch 

 of this type was brought up from Bempton cliffs in June 1902, 

 while I was present. In the event of the bird being obliged 

 to produce a second clutch the first egg is at once sat on, 

 consequently it may thus happen that eggs from the same nest 

 are in different stages of incubation, and in July 1904, 1 noticed 

 young in variant degrees of growth in one nest. If the nest 



