684 U.S. NATIONAL MUSEUM BULLETIN 237 part 2 



The character of the vegetable food shows the savanna sparrow to be a great 

 consumer of grass seeds. * * * Other seeds, mainly * * * weed seeds * * * 

 make practically all of the remaining 22 percent of the vegetable matter, the only 

 exception being a few blueberries found in one of the stomachs." 



Martin, Zim, and Nelson (1951) show that for Savannah sparrows 

 in the United States, the diet consists largely of plant food, mostly 

 seeds. When considered seasonally, plant food composes 92 percent 

 of the diet in winter, 63 percent in spring, 26 percent in summer, and 

 84 percent in fall. Animal food, mostly insects, is most heavily 

 utilized in the late spring and summer. The most frequently utilized 

 food plants (5 to 25 percent of the diet) in the northeast are bristle- 

 grass, crabgrass, ragweed, and panicgrass; in the southern prairies, 

 panicgrass, goosegrass, and pigweed; in California, knotweed, turkey- 

 mullein, pigweed, and oats; in southern California and Mexico, wild 

 oats, nightshade, and barley. 



The early food habits studies carried on by Judd et al. were, of 

 necessity, qualitative and "economic" m character; they fulfilled a 

 definite need and are singularly useful even today. But these are 

 yesterday's studies; today, food habits studies must meet the challenge 

 of such concepts as "biomass" and "energy cycle." The Savannah 

 sparrow, because of a decided predilection for fields in early stages of 

 succession on its wintering ground, has been the subject of several 

 recent papers dealing with old-field ecosystems (Odum and Hight, 

 1957; Quay, 1947, 1957, 1958; Norris, 1960). 



To Odum and Hight (1957) the Savannah sparrow is an "herb 

 sparrow," which they define as a sparrow that does not require woody 

 vegetation but finds all food and habitat requirements in herbaceous 

 vegetation. Quay (1957) defines the Savannah sparrow's winter 

 habitat requirements: "Thus, the habitat niche of the Savannah 

 sparrow in winter around Raleigh [North Carolina] was found in the 

 ground level stratum of a particular facies (Digitaria) of one life-form 

 of vegetation (grass). This niche was composed in large measure of: 

 (1) bare ground on which to move and forage, (2) an abundance of 

 small seeds easily visible from the ground surface and available without 

 scratching, (3) an overhead cover of low to mediumly tall grass." 



However, the Savannah sparrow is moderately abundant in many 

 grassland associations and is concentrated only around favored seed 

 sources. In South Carolina, an abundance of Paspalum attracted 

 and maintained a large concentration of Savannahs (Odum and Hight, 

 1957), while in North Carolina, there was an almost linear relationship 

 between the abundance of Digitaria (crabgrass) and the number of 

 Savannahs (Quay, 1957). 



Quay (1958) summarizes his work on the Savannah's foods and 

 feeding habits as follows: 



