404 University of California Publicafions in Zoologij [Vol. 11 



Nesting Habits 



The nesting season of the western meadowlark lasts from 

 March to August. The nest is a well-concealed one, built of 

 dry grasses usually in grass, alfalfa, or grain fields, in a de- 

 pression in the ground. A canopy of dry grass stems usually 

 arches the top of the nest and a runway two to five feet long 

 leads to the nest. Ofttimes this runway is the only clue to the 

 location of the nest. The female bird does most of the work 

 of incubation and feeding of the j'oung, while the male acts as 

 a guard. Eggs are usually five and are white, variou.sly marked 

 with brown, purple, and lavender spots and lines. 



Work in the spring of 1911 and 1912 substantiated the fact 

 that western meadowlarks usually nest twice each year. The 

 first nesting usually occurs in April and May and the second 

 in July and August. Probably on an average not more than 

 three young are in a brood, although the number of eggs laid is 

 usually five. Second nestings examined usually show an incom- 

 plete set of eggs. A preference for pasture land for nesting 

 sites was shown, at least eighty per cent of the nests found being 

 so situated. The time of incubation was found to be twelve to 

 fourteen days. The young sta.y in the ne.st but a short time, 

 eight to ten days. Nestlings are exposed to many enemies, such 

 as skunks, weasels, rats, and hawks, and the number of broods 

 successfully reared is less than that of most other birds. That 

 over ten per cent of the nests in most localities are destroyed by 

 predacious animals and birds seems a very conservative estimate. 



These facts have an important bearing on the economic rela- 

 tions of the meadowlark. Proximity of breeding grounds to 

 cultivated crops naturally has an influence on the amount of 

 damage done. The rate of reproduction influences the amount 

 of damage, owing to the number of individuals to be expected 

 in any locality. 



Depredations of the Western Meadowlark 



No small part of the field work has consisted in investigations 

 of the damage caused by the western meadowlark. In most cases 

 the field work has been supplemented with stomach examinations. 



