Scientists from the U.S. National Oceanic and Atmospheric Administration say the temperature at which turtle eggs incubate determines the sex of hatchlings, and warn that warmer conditions are creating a dangerous gender imbalance.
Colin Limpus, Queensland chief scientist, says that cloud seeding is another option.
The reef faces a range of threats from the run-off of pesticides and soil from farms, and warmer ocean temperatures that have caused the mass bleaching of the coral in the past two years.
In the southern Barrier Reef, where conditions are cooler, about two-thirds are female. Researchers say that while they hope for some milder years to produce more males, they expect temperatures to continue to rise.
One possible solution to the gender imbalance is to put up tents over beaches where turtles nest to give them shade.