Spartina alterniflora is a typical alien invasive grass species with high reproductivity and adaptability but few natural enemies. S. alterniflora reduces the biodiversity and alters the structure and functions of the coastal tidal wetland ecosystem. The Père David's deer Elaphurus davidianus, a Level I national protected species in China, is a paragon of wildlife ex-situ conservation. However, the increasing deer population may induce significant concerns, e.g., the lower stability of wild populations and the decrease of the environmental carrying capacity of conservation areas. E. davidianus prefers S. alterniflora for grazing, and the grazing activities regulate the spatio-temporal distribution of S. alterniflora, which could potentially improve the functions and stability of the coastal tidal wetland ecosystem. Meanwhile, it could be beneficial to accelerate the return to the wild state process for E. davidianus. Although some work focusing on E. davidianus conservation and S. alterniflora prevention has been done, few researches paid attention to their interaction mechanisms. Here, we illustrated the coupling development model and potential interaction mechanisms of E. davidianus and S. alterniflora based on the grassland agroecosystem theory (i.e., nature-based solutions for overcoming system discordance). We then attempted to break the traditional pattern that split the endangered species conservation and invasive species prevention, and explored the guidelines and practice of terrestrial-marine agriculture. Finally, we discussed the UAV-based space-air-ground integrated monitoring and analysis system for E. davidianus conservation and S. alterniflora prevention.