The Lesser Siren (Siren intermedia) is a fully aquatic salamander with functionally limited overland dispersal. Details of the ecology of this species throughout its geographic range and diversity of habitats are limited. In this study, I investigated the ecology of a presumably isolated population of S. intermedia in eastern Texas. The conservative estimated population density was 0.33 sirens/m² with a standing crop biomass of 9.66 g/m². Growth rates averaged 0.022 mm/day in total length, slightly slower than other populations. Growth rate was not significantly different between males and females, nor was it correlated with size. The diet of the study population included at least 10 different taxa, of which tadpoles and snails (Order Basommatophora) were the most important prey. Like other populations, activity was highest during late winter and early spring, which coincides with the breeding season. The abundance of siren captures was weakly influenced by water temperature but not correlated with precipitation. Bite marks are hypothesized to be a result of siren courtship behavior. The abundance of males and females captured with fresh bite marks was significantly correlated with the number of gravid females. Because sirens are predatory generalists and represent a significant proportion of biomass in many aquatic environments, it is important to understand siren ecology throughout its geographic range and broad use of habitat types.