As land development continues to reduce wild areas, wildlife is forced into closer proximity with human communities like Mequon. Large mammals, including white-tailed deer, coyotes, and red foxes can be seen in the city. Many birds, including chimney swifts, great blue herons, and wild turkeys are found in the city. The city is also home to many rare and notable species, including the state-designated endangered pinedrops and heartleaf plantain; threatened forked aster, snow trillium, and yellow gentian; as well as American gromwell and twinleaf, which are state-designated special concern plant species.