This paper examines potential relations between factors related to fertility (e.g., family size, desired family size, contraception, and household composition) and the access to and use of natural resources in Petén, Guatemala. The Petén forms the heart of the Selva Maya, the largest lowland humid forest in Mesoamerica. The rapid in-migration of subsistence maize farmers has converted much of the Petén’s forests to agricultural fields. Population dynamics have been distinctive in that virtually all farm families have arrived since the 1970s and that total fertility rates exceed the national rural mean. Continued migration, exceptionally high fertility, a youthful population, and a large consumer to producer ratio are hypothesized to be related to the dramatic land cover dynamics shaping the landscape of the Petén. An emerging body of literature suggests that environmental factors can affect fertility decision-making and behaviors, especially in natural resource dependent economies like that of the Petén. This paper examines these relationships using data from the 1998/99 Demographic Health Survey in Guatemala. Data on natural resource access and utilization were collected as part of an environment module, in addition to demographic and health information. This dataset provides a unique opportunity to examine possible relationships between fertility and the environment in a tropical agricultural frontier.