Produced by Chris Curnow, Joseph Cooper and the Online Distributed Proofreading Team at http://www.pgdp.net UNIVERSITY OF KANSAS PUBLICATIONS MUSEUM OF NATURAL HISTORY Vol. 10, No. 2, pp. 45-75, 6 pls., 1 fig. December 20, 1956 Comparative Breeding Behavior of Ammospiza caudacuta and A. maritima BY GLEN E. WOOLFENDEN UNIVERSITY OF KANSAS LAWRENCE 1956 UNIVERSITY OF KANSAS PUBLICATIONS, MUSEUM OF NATURAL HISTORY Editors: E. Raymond Hall, Chairman, Henry S. Fitch, Harrison B. Tordoff Volume 10, No. 2, pp. 45-75, 6 pls., 1 fig. Published December 20, 1956 UNIVERSITY OF KANSAS Lawrence, Kansas PRINTED BY FERD VOILAND. JR., STATE PRINTER TOPEKA, KANSAS 1956 Comparative Breeding Behavior of Ammospiza caudacuta and A. maritima BY GLEN E. WOOLFENDEN Transcriber's Note: There are three symbols used in the caption for Figure b in Plate 1 which are not available in the Latin-1 character set. They have been noted as follows: For the black triangle --> [triangle]. For the black dot --> [dot]. For the five pointed star --> [star]. CONTENTS PAGE INTRODUCTION 48 MATERIALS AND METHODS 48 DESCRIPTION OF THE AREA 49 FLORA 50 REPTILES 50 MAMMALS 50 PREDATORS 50 PASSERINE ASSOCIATES 51 WINTER STATUS AND SPRING MIGRATION 51 TERRITORY 52 VOICE 58 Song 58 Calls 60 COPULATION 61 NESTS 62 EGGS AND INCUBATION 65 YOUNG 65 Growth 65 Behavior 68 FOOD, FEEDING AND CARE OF THE YOUNG 71 ACKNOWLEDGMENTS 73 SUMMARY 73 LITERATURE CITED 74 INTRODUCTION Taxonomically the Genus _Ammospiza_ has received the attention of ornithologists for more than a century. Nevertheless, the behavior of no species of the genus has been studied extensively. The papers of Montagna and Tomkins are the only works that mention behavior and natural history in any detail. There has been an increasing awareness of the importance of ethological data and of their usefulness in systematics. For these reasons, I made a comparative study of the breeding behavior of the Sharp-tailed Sparrow (_Ammospiza caudacuta_) and the Seaside Sparrow (_Ammospiza maritima_) in New Jersey in the spring and summer of 1955.