A 12-year-old boy who was hospitalized after being bitten by a shark in Sydney Harbour has died of his injuries, his family announced Saturday, amid a wave of concern caused by a series of such attacks.

Nico Antic was seriously injured last Sunday by a bull shark while jumping off a rock to swim with friends in a cove in Australia's largest city.

This attack is the third deadly one in Sydney since September. It was followed by three other, non-lethal attacks in the following 48 hours in the state of New South Wales, of which Sydney is the capital, prompting rescue workers to urge the public to avoid the beaches.

"We are devastated to announce that our son, Nico, has passed away," his parents Lorena and Juan said in a statement.

"Nico was a happy, sociable and sporty young boy who showed great kindness and generosity. He was always full of life, and that is how we will remember him," they added.

Increasingly crowded waters and rising ocean temperatures, which appear to be affecting shark migration patterns, could contribute to an increase in attacks, despite overfishing which is reducing the population of some species, according to scientists.

The coastal region has also been affected in recent days by rainfall that has made its waters murky. This creates an ideal environment for bull sharks, according to the marine rescue organization Surf Life Saving New South Wales.

On Tuesday, a surfer was bitten by a shark at sea and slightly injured, according to Surf Life Saving New South Wales. This marks the fourth shark attack in New South Wales in the space of two days.

Drones and nets

During one of these incidents, in Manly on the outskirts of Sydney, a shark attacked the legs of a surfer, who has since been in critical condition.

A few hours earlier, an 11-year-old child had escaped unharmed from a shark attack that had bitten his surfboard, a little further north.

Dozens of beaches in Sydney's northern suburbs are closed until further notice, while surveillance of others, including with the use of drones, has been increased.

"The water quality is so poor that it's encouraging bull shark activity," Surf Life Saving New South Wales told the ABC on Tuesday. "Just go to the local swimming pool, because at this point we consider the beaches unsafe."

More than 1,280 incidents involving sharks in Australia have been recorded since statistics began in 1791, of which more than 250 resulted in the deaths of those bitten, according to a database detailing human-shark interactions.

In September, a great white shark killed a surfer on a busy beach north of Sydney. Two months later, a bull shark killed a woman swimming off a secluded beach north of the same city.

In addition to deploying drones, authorities put up shark nets every summer off the coasts of New South Wales and Queensland to prevent attacks.

Official data, however, shows that these nets capture endangered turtles, dolphins, fish or rays.

AFP