ANNALS OF CARNEGIE MUSEUM VOL. 84, NUMBER 4, PP. 265–285 31 OCTOBER 2017 COPROLITES AND MAMMALIAN CARNIVORES FROM PIPESTONE SPRINGS, MONTANA, AND THEIR PALEOECOLOGICAL SIGNIFICANCE DONALD L. LOFGREN [Research Associate, Section of Vertebrate Paleontology, Carnegie Museum of Natural History] Raymond M. Alf Museum of Paleontology, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] CLIFFORD Y. S HEN The Webb Schools, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] NAOMI N. BUDAY The Webb Schools, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] CLARISSA A.C. YLAGAN The Webb Schools, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] KATHRYN K. LOFGREN The Webb Schools, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] REBECCA LAI The Webb Schools, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] DAKOTA D. SANTANA-GRACE The Webb Schools, 1175 Baseline Road, Claremont, California 91711-2199
[email protected] ALAN R. TABRUM Section of Vertebrate Paleontology, Carnegie Museum of Natural History, 4400 Forbes Avenue, Pittsburgh, Pennsylvania 15213 (deceased) ABSTRACT Pipestone Springs Main Pocket (PSMP) (Renova Formation, Jefferson County, Montana) has yielded an unusually rich concentration of mostly small-bodied Chadronian (late Eocene) mammals. Coprolites are common at PSMP and indicate which taxa and skeletal elements were consumed, as well as provide insight as to which carnivore species were likely to have deposited their feces at the site. Two distinct coprolite groupings were recognized based on differences in diameter, morphology, and abundance of bone. The sample of larger coprolites ranges in diameter from 16–29 mm and lacks a distinct mode.