LARK SPARROW 895 



sides, and flanks profusely streaked with black. Belly (lower) and 

 orissum immaculate. Leg feathers white." 



The first winter plumage is similar to the juvenal plumage, except 

 that it is not streaked below and shows a dark brown central chest 

 spot. The head pattern is very distinct — crown light brown, a well- 

 defined buffy superciliary stripe, rictal and loral streaks black, auric- 

 ulars chestnut. No specimens examined showed any molt of the 

 juvenal remiges; although some rectrices were replaced in a few 

 specimens, first winter birds are easily recognized by the presence of 

 a light brown spot at the tip of the four outer rectrices. This spot is 

 lost by feather wear and is not present on spring specunens. 



The nuptial plumage resembles the first winter plumage, but a 

 partial molt of feathers on the head, chin, and throat makes these 

 areas appear somewhat brighter; the rectrices and remiges are usually 

 badly worn and frayed. 



The adult winter plumage, acquired by a complete postnuptial 

 molt, and occurring in Oklahoma during July and August, resembles 

 the first winter plumage, but its colors are slightly more intense and 

 the markings on the outer tail feathers are solid white. 



The sexes are sunilar in appearance in all plumages throughout the 

 year. 



Food. — Few detailed studies of the lark sparrow's food habits have 

 been made. F. M. Bailey (1928) writes that in New Mexico its diet 

 consists of: 



Insects 27 per cent and seeds 73 per cent. The lark sparrow, with the exception of 

 the grasshopper sparrow * * * is the most valuable grasshopper destroyer of 

 our native sparrows. More than half its animal food is grasshoppers. On the 

 prairies and plains it also does much good in helping to check the invasions of 

 the Rocky Mountain locust. In an outbreak of locusts, they made up over 91 

 per cent of its diet. It also cats great numbers of alfalfa weevils. One half of 

 its vegetable food consists of seeds of grain and grass. Pigeon grass and Johnson 

 grass are both eaten freely. The weed seed, including pigweed, destroyed, more 

 than twice outweighs the grain consumed, and the grain is doubtless largely 

 waste; beneficial insects are less than 1 per cent while injurious insects, including 

 the alfalfa weevil, constitute 25 per cent of the food. 



T. S. Roberts (1936) adds from the U.S. Biological Survey report: 

 "Grass-seeds (including pigeon- and panic-grasses), and waste grain; 

 seeds of ragweed, knot-weed, wild sunflower, purslane, etc. More 

 than 14 per cent of its total diet consists of grasshoppers; other 

 animal matter taken consists of weevils, caterpillars, and other 

 insects." 



At Lake Texoma adults gathered food for their young from an 

 unmowed section of the lawn where the gi'ass grew some 15 inches 

 tall. Here they captured small grasshoppers and the larvae of other 

 insects, each adiJt returning to the nest with several insects in its 



64&-737— 6S— pt. 2 20 



