Researchers from Queensland's James Cook University are worried dugongs could be caught in the crossfire of the NSW government's war on sharks in the state's northern beaches.
The government fast-tracked a six-month trial of shark nets in Ballina earlier this month, after three attacks on surfers in the region across six weeks.
However a JCU monitoring team has proved that dugongs are especially vulnerable to shark nets.
Professor Helene Marsh said they used GPS trackers to show when migrating, dugongs stay within 5km of the coast.
"The data shows they were much more likely to encounter shark nets than if they'd been moving off shore," Prof Marsh told AAP.
Thirty-nine dugongs were recorded drowned in shark nets in Queensland from 1989 to 2011, and Prof Marsh said she was worried the introduction of shark nets in northern NSW would compound the problem.
"What we do know is when numbers (of dugongs) are low, even low numbers being caught in nets is dangerous, and this is just an added risk, where policy makers need to weigh up the risk to people versus the risk to wildlife."
