The Current Biology paper says the northern Great Barrier Reef population of more than 200,000 nesting females – one of the largest in the world – could eventually crash without more males.
Increasing temperatures in Queensland's north, linked to climate change, are being blamed because the incubation temperature of eggs determines the sex of turtles with a warmer nest resulting in more females.
WWF-Australia CEO Dermot O'Gorman said: "First back-to-back mass coral bleaching and now we find that virtually no male northern green turtles are being born.
"These impacts show that the Great Barrier Reef really is at the frontline of climate change. Australia must adopt ambitious climate change targets that will save the Reef and its unique creatures."