The great hammerhead sharks’ role as apex predator is essential to maintaining a healthy ecosystem in the waters off eastern Australia, according to new research.

The study, conducted by researchers from Macquarie University and published in the Journal of Fish Biology, found that large sharks over three meters helped maintain marine food webs by preying on lesser predators like whaler sharks and manta rays.

“Until now the role of these sharks in the food webs of coastal ecosystems has been poorly understood,” said lead researcher Dr. David Raoult. “What our research has found is that the great hammerhead shark is in fact the ‘shark predator’, it confirms that they are at the top of the food chain and highlights that their role in our coastal ecosystem is absolutely crucial.

“Apex predators keep the balance of our ecosystem in check, they keep it healthy, so this discovery about the great hammerhead really emphasises its importance.”

The species are listed as Vulnerable in NSW and the decline in the population reflects demand for their fins, commercial fishing activities and that they are often bycaught in bather-protection programs involving gillnets and drumlines off eastern Australia.

“We know that the great hammerhead is vulnerable to commercial and recreational fishing, and that they die very easily when released after capture,” said Dr Raoult.

“Now that our study has shown just how important their role is in linking coastal food webs, it is absolutely crucial that we see urgent conservation of the species. As apex predators their extinction would have a vast ecological impact on the coastal ecosystem and protection is essential to support stability across economically important coastal ecosystems.”