their occurrence may be desirable. (4) Each crop of large or small volume has its full influence on final results. The aggregate percentage method automatically suppresses the significance of full crops and magnifies that of lower-content crops. These interpretative adjustments complicate and hamper later conclusions. The preferable course is to segregate data, on one basis or another (seasonal or sub-seasonal, locality, and possibly crop-volume) so that full significance is expressed for all specimens, whether gorged, average, or of low-content. Some low-content crops may reflect nibbling or sampling in areas where staple foods are absent; and distended crops obtained in seasons or localities having variety in available foods may express definite relish of a preferred food. Distended crops in winter may reveal other sorts of preference circumscribed by availability; stuffed crops in adverse weather may indicate dire necessity and little choice. These and similar interpretations on extent of use, preference, and availability are important in food studies on upland gamebirds. They can be obtained best by intelligent use of the aggregate volume method. A question may be raised as to whether aggregate volume and aggregate percentage data in different studies are comparable. Is it appropriate to compare winter foods of bobwhite quail from two adjacent states if the data are obtained by the two divergent methods? In our opinion there should be no concern. There are many variables-adequacy and geographic representativeness of the specimens, fluctuations or periodicity in food availability and use, variations in individual methods of analysis-and other uncontrolled factors. These outweigh considerably the disparity in results from the two methods. Yet it is of interest and value in all food habits reports, that authors clearly indicate the statistical method used.
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