First Nations ranger groups in the Northern Territory have highlighted illegal commercial fishing as a major threat to green turtle populations, according to a recent study led by Charles Darwin University (CDU) and James Cook University (JCU). Published in the journal Biodiversity and Conservation, the research mapped six human-caused dangers affecting turtle habitats, including climate change, commercial fishing, industrial development, coastal construction, shipping, and nest predation. The study identified nest predation, rising sea levels, traditional hunting, and industrial pollution as the most pressing threats. Darwin Harbour was found to have the highest concentration of these overlapping threats, such as artificial light, recreational boats, oil and gas infrastructure, and industrial projects. Channel Island, meanwhile, was identified as the area with the highest risk for turtles foraging for food. Dr. Natalie Robson, a recent Ph.D. graduate from CDU’s Research Institute for the Environment and Livelihoods, explained that the study differed from previous research due to the deep involvement of eight First Nations ranger groups. These groups provided critical insights into local conditions, uncovering issues like illegal fishing that might otherwise be overlooked. "Local knowledge from the rangers is essential for understanding real-world challenges," Robson said. She noted that while threats like plastic pollution and climate change were anticipated, the rangers pointed out illegal commercial fishing in protected areas such as Kakadu and Garig Gunak Barlu National Parks. This kind of activity is hard to track using traditional methods, as fishing vessels often turn off their tracking systems when entering marine parks. Alex Tomlinson, the Kakadu Country Conservation Manager, praised the collaboration between the Kakadu rangers and Parks Australia, which contributed to a better understanding of green turtle conservation. He emphasized the rangers’ deep knowledge of the land and its species, saying that their insights are vital for protecting the marine environment. "Green turtles are not only ecologically important but also culturally significant to First Nations communities," Tomlinson said. The research highlights the value of combining Indigenous knowledge with Western science to address environmental challenges. Dr. Robson noted that the findings from her study are available through an online dashboard, allowing rangers and community groups to access the data. This tool helps land managers and government officials make informed decisions about development and conservation efforts. "This information helps rangers clearly communicate their concerns to those who may not fully understand the unique environmental challenges in the Northern Territory," she said. The study underscores the growing recognition of Indigenous rangers’ role in conservation and their contributions to protecting vulnerable species like green turtles.