Mangrove encroachment is shifting the food sources available to basal consumers in Gulf of Mexico salt marshes, so we sought to determine how two important basal consumers will respond to mangroves as a food source. We collected Littoraria irrorata and leaves of Spartina alterniflora, and Avicennia germinans from marshes in Galveston, Texas in summer of 2020 for a series of food preference and food quality studies. Additionally, we compared the physiological conditions of Littoraria irrorata and Uca rapax individuals collected from manipulated sites with varying levels of mangrove cover in Port Aransas, Texas in late 2020 and early 2021. These studies yielded results on the behavioral and physiological responses of basal consumers to mangrove plant matter as a food source.