This dataset consists of occurrence observations for white-tailed deer in the National Park Service Heartland Inventory and Monitoring Network Parks. Because of their impacts on vegetation, disease transmission, visitor health, and vehicle-deer collisions, park managers at Arkansas Post National Memorial, Pea Ridge National Military Park, and Wilson’s Creek National Battlefield identified white-tailed deer as a vital sign for monitoring. Monitoring white-tailed deer populations better positions park management to take action to mitigate concerns involving deer. The overall goals of HTLN white-tailed deer monitoring are to 1) document annual changes in the number of white-tailed deer, as changes could signal presence of illegal deer harvest, disease, or other acute factors of concern for park management; 2) document long-term trends in the number of white-tailed deer to help park management determine if measures need to be taken to maintain herd health, minimize vegetation damage within a park, or alleviate visitor health concerns; and 3) annually map locations of white-tailed deer observed to assist park management in assessing the influences of management actions on deer usage of an area, habitat type, etc.