Sparrow-Hawk 203 



Of the three families of nestlings : 



(i) May 28th, 1913 ; live very small nestlings, probably not 

 more than two days old ; nothing was found in crop and stomach. 



(2) July 4th, 1913 : five half-grown nestlings ; stomachs of 

 all five birds loaded with Pheasant-chick remains. 



(3) J^ly 7th> 1909 ; six three-quarter-grown >oung biixls ; 

 all contained passerine remains, and nothing else. 



From this evidence we may infer that one family out of three 

 drew supplies from the rearing-field. 



It is the rule in the family [Falconidce] with which we are dealing, 

 that the female is larger than the male. In some cases the Hobby, 

 Merlin and Kestrel, for example, this sexual difference is not very 

 marked. In the Eagles, Buzzards and Harriers it is considerable, 

 but in two of our British Raptors — the Peregrine-Falcon and the 

 Sparrow-Hawk — the difference reaches an extreme limit. The 

 females are much larger and nearly double the weight of the males. 

 The female Peregrine weighs some two pounds four ounces, and has 

 a total length of twenty inches, against a weight of one pound 

 eight ounces, and a length of eighteen inches in the male. 



In the Sparrow-Hawk, the adult female weighs, on the average, 

 ten ounces, the adult male live ounces ; in length, the female 

 ■measures fifteen inches, the male twelve-and-a-half. 



This very great difference in the size and weight between the 

 males and females is of considerable importance. For while the 

 cock bird can hardly manage anything above the size of a Blackbird, 

 the hen will successfully attack much larger game, even Wood- 

 Pigeons and Partridges. 



The depredations that a male Sparrow-Hawk could possibly 

 carry out on game must, therefore, be confined to the breeding season, 

 while the birds remain small. At this time he may take Pheasant 

 or Partridge or farm-yard chicks, but as these grow in size, they 

 become immune from capture. 



With the female it is quite otherwise. The first Sparrow-Hawk 

 in Table II., an immature female, killed an adult female Partridge 

 just after daylight on the 13th of April, 1892 : and we trapped her 

 at the remains an hour afterwards. Now, a female Grey Partridge 

 weighs, on the average, fourteen ounces or a little more, and is 

 consequently too heavy for the Hawk to lift. The same is true of 

 wild or domestic Pigeons. The Hawk kills them, and has to eat 

 them where they lie ; she can generally be trapped at the remains 

 without much difficulty. 



On July nth, 1894, an immature female Sparrow-Hawk 

 (Table II., 17) was shot in one of the rides of the Scots Hall big 

 wood, carrying in her talons a young Pheasant, which was headless, 

 and weighed in this state just over six ounces. The missing head 

 we subsequently found in the Hawk's interior. I am inclined to 

 think that six ounces is about as much as they can comfortably 



