The article discusses the status and ecological effects of the world's largest carnivores, highlighting their critical role in maintaining biodiversity and ecosystem function. These species, which include lions, leopards, dingoes, Eurasian lynx, sea otters, gray wolves, and pumas, are facing severe threats such as habitat loss, persecution, and human conflict. Despite their large size and high metabolic demands, these carnivores often require vast habitats and large prey, leading to conflicts with humans and livestock. Empirical studies show that these species have significant trophic cascading effects on ecosystems, influencing the abundance and distribution of various species, including plants, prey, and scavengers. The loss of these carnivores can lead to ecosystem degradation, reduced biodiversity, and altered ecological processes. The article emphasizes the need for conservation efforts to protect these species and their habitats, as their extinction would have irreversible consequences for ecosystems and human societies. It calls for a Global Large Carnivore Initiative to coordinate research, conservation, and policy efforts to ensure the survival of these important species. The article also highlights the economic and ecological services provided by large carnivores, including tourism, carbon storage, and disease control. The conservation of these species is essential for maintaining the balance of ecosystems and ensuring the resilience of biodiversity in the face of human activities and climate change.The article discusses the status and ecological effects of the world's largest carnivores, highlighting their critical role in maintaining biodiversity and ecosystem function. These species, which include lions, leopards, dingoes, Eurasian lynx, sea otters, gray wolves, and pumas, are facing severe threats such as habitat loss, persecution, and human conflict. Despite their large size and high metabolic demands, these carnivores often require vast habitats and large prey, leading to conflicts with humans and livestock. Empirical studies show that these species have significant trophic cascading effects on ecosystems, influencing the abundance and distribution of various species, including plants, prey, and scavengers. The loss of these carnivores can lead to ecosystem degradation, reduced biodiversity, and altered ecological processes. The article emphasizes the need for conservation efforts to protect these species and their habitats, as their extinction would have irreversible consequences for ecosystems and human societies. It calls for a Global Large Carnivore Initiative to coordinate research, conservation, and policy efforts to ensure the survival of these important species. The article also highlights the economic and ecological services provided by large carnivores, including tourism, carbon storage, and disease control. The conservation of these species is essential for maintaining the balance of ecosystems and ensuring the resilience of biodiversity in the face of human activities and climate change.