The National Wildlife Refuge System is the largest system of public lands in the United States, and it is tasked with protecting some of the nation's most important natural resources. However, the system is not without its problems. One of the biggest issues facing the National Wildlife Refuge System is funding. The National Wildlife Refuge System is funded primarily through appropriations from Congress. However, Congress has been increasingly reluctant to fully fund the system in recent years. As a result, many refuges are underfunded and struggling to provide adequate protection for their resources. Another big problem facing the National Wildlife Refuge System is invasive species. Invasive species are non-native plants, animals, or pathogens that can cause harm to native ecosystems. Many refuges are struggling to control invasive species, which can damage or destroy native habitat. The National Wildlife Refuge System is a vital part of the United States' conservation efforts. However, the system faces significant challenges that must be addressed in order to ensure its long-term success.