
Reproductive Capacity 
The reproductive capacity of the red-legged partridges in 
Spain closely resembles that of the chukar as wi tt be seen from the 
following analysis. ) 
Breeding age -- Redlegs breed the first year after hatching. 
Number of eggs -- The normal clutch is 10 to 16 eggs though 
20 have been recorded (a). 
Brood survival -- Said to be good except in very wet or very 
dry years. 
Life span -- In captivity up to 5 to 6 or more years. 
Sex ratio -- Not much out of balance. Of some 2,000 birds 
caught for the Foreign Game Introduction Project between 1953 and 1957, 
either by hand, in nets or in snares, there was a slight preponderance 
of males over females. 
Renesting -- Will renest if the first nest is destroyed. 
Second broods -- There is some evidence that the female 
occasionally will lay two clutches of eggs, either raising two broods 
in the same season or turning one clutch over to the male to incubate 
and to raise the resulting chicks (a). 
Parasites and Diseases 
Almost no work has been done on the parasites and diseases of 
the red-legged partridges of Spain. Indications are that they suffer 
from the same maladies as do the chukars. Like this bird, the redlegs 
are quite resistant to many poultry diseases, for callers held in 
captivity, often in close association with poultry and under unsanitary 
conditions, frequently live for 5 to 6 years. 
During the course of the investigation many birds were examined 
by veterinarians associated with the Veterinary School, University of 
Madrid. Only two maladies, Newcastle disease or fowl pest, and cocci-- 
diosis, were commonly identified in the birds held in captivity. 
Coccidiosis is certainly endemic in the wild redleg population. It is 
probable, though currently unproven, that some wild birds are also 
infected with Newcastle disease by association with wide-ranging farm- 
yard fowl, since this disease is widespread in Spain. After one disas- 
terous experience with Newcastle all birds held in Madrid in captivity 
by the Foreign Game Introduction project were injected twice, once 
upon arrival and again 30 days later, with 0.5 cc. of killed Newcastle 
vaccine. Thereafter no losses from this disease were encountered. 
(a) Unpublished records of observations by Mr. Quiros. 
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