PARASITIC WEAVERBIRDS 101 



Lynes (1924, p. 678) concluded, from his Darfur specimens and 

 notes, that the pintail, like the paradise widow bu"d and some of the 

 bishop birds, does not assume adult plumage or begin to breed until 

 the second year. His conclusion also accounts for the difference 

 between the apparent and the true picture of the constituents of the 

 small flocks found in the breeding season. Chapin and V. G. L. van 

 Someren are also of the same opinion. 



There may be more pintail males than females, a situation common 

 in parasitic birds such as cowbirds and other widow birds. V. G. L. 

 van Someren (1919, p. 414) once collected 30 live birds in off-season 

 plumage for his aviaries in January, and found that only 7 turned out 

 to be females. The birds were alike until April, when the males 

 assumed their nuptial feathering. In the small breeding season 

 flocks that I studied, random collecting revealed more immature or 

 nonbreeding males than females. 



Eggs and Egg Laying 



The eggs of the pintail are pure white, and vary from 14.5 to 16.6 

 by 11.0 to 12.2 mm. They are definitely known from eggs laid by 

 captive birds (Bolus, 1909, p. 113, and Feo, 1910, pp. 145-146) and 

 from fully shelled oviduct eggs taken from wild killed pintails (Ban- 

 nerman, 1923, p. 682; Godfrey, 1929, pp. 117-118). There are other 

 eggs whose identity seems in no doubt and that may also be taken as 

 authentically known reference specimens, such as several sets from 

 the Karkloof District of central Natal where the pintail is the only 

 species of Vidua present. 



In the majority of cases only a single egg is laid in any one nest, 

 but I have data on numerous nests with two, three, and fom- eggs of 

 the parasite. There are no data whether these multiple eggs are the 

 product of one or of several hens. No one has witnessed the bird 

 actually laying its egg, although several observers have noted hens 

 entering nests of waxbills. Therefore, we do not know positively 

 whether the laying hen destroys or removes an egg of the host before 

 laying its own, although there are pronouncements on this matter in 

 the Hterature. Thus, A. Roberts (1939, pp. 106-107; 1940, p. 361) 

 stated that an egg of the host is "destroyed to make room for each of 

 those of this parasite, and thereafter the young grow with the 

 others in amity." Neuby-Varty (in litt.) Nvrote me that the pintail 

 may remove some eggs because he has never found parasitized nests 

 of the common waxbill with as many eggs as in unmolested nests. 

 Chapin (1954, pp. 573-577) noted that the "laying widow bird has 

 been accused of destroying one of the legitimate eggs." On the other 

 hand V. G. L. van Someren (1956, pp. 501-503) stated: "One, two, 

 or rarely three eggs may be laid in the foster parent's nest. It de- 



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