Bryce Canyon National Park: Paleontological resource inventory

Abstract

Originally designated as a national monument in 1923, Bryce Canyon National Park (BRCA) is recognized for its exceptional pink-orange hoodoo landscapes. Its iconic hoodoos, consisting of the Paleocene?Eocene Claron Formation, are only part of the geology of BRCA, which includes a nearly uninterrupted sequence of Late Cretaceous Western Interior Seaway evolution and diverse depositional environments from approximately 100 to 77 million years ago. This sequence consists of the coastal Naturita Formation, the marine Tropic Shale, the transitional Straight Cliffs Formation, and the terrestrial Wahweap Formation. These strata, and the Claron Formation, preserve diverse paleontological resources. Fossils at BRCA have received little visibility for most of the park?s history, despite relatively rapid advances in the study of Late Cretaceous and Paleogene paleontology in neighboring public lands, especially Grand Staircase-Escalante National Monument (GSENM) to the east. The best documentation of paleontological resources at BRCA was produced through concerted field inventory of the park conducted by Dr. Jeff Eaton and several cohorts of interns and students from 1988 to 2015. In that time, Eaton?s team documented nearly 200 paleontological localities within the park that yielded clams, snails, fish, frogs, turtles, lizards, snakes, crocodilians, dinosaurs, and mammals from the Straight Cliffs and Wahweap Formations and invertebrates, plants, and trace fossils in the Claron Formation. Eaton?s survey resulted in several publications, including the description of new microvertebrate species from the Straight Cliffs and Wahweap Formations. Despite this body of work, the park did not develop an internal paleontological resources management program. A new paleontological resources program at BRCA was advanced in response to construction activities that impacted several fossil localities in the Wahweap Formation. Newly hired paleontological staff conducted two seasons of field inventory (2022?2023), relocating as many of Eaton?s sites as possible and recording new fossil occurrences along the way. In this timeframe, BRCA paleontologists encountered more than 150 localities. They also conducted detailed literature review, examined the park?s paleontological collections data, and cultivated partnerships with outside researchers to better comprehend the current state and future potential of the park?s paleontological resources. This document synthesizes the total current body of knowledge on paleontological resources at BRCA to create a comprehensive paleontological inventory report. It combines historical data from the scientific literature, previous work conducted in the park, and recent fieldwork to cover BRCA?s geologic history and fossil diversity and the history of paleontological study, education, and resources management in the park.