A 150kg mako shark hooked by a fisherman in a Sydney river proves the harbour and its rivers are in good health, a marine expert says.
Many were surprised when angler Patrick Melograna and his mates caught the 2m mako when fishing on the Parramatta River near the Gladesville Bridge on the weekend.
The species usually inhabits open ocean rather than river waters.
“The moment one of the boys picked up the rod, they knew it was something big,” Melograna told the Seven Network.
“To see something this big come out of Parramatta River we were blown away.”
Some people hypothesised the animal was sick and disoriented, but Macquarie University marine predator expert Professor Rob Harcourt believed the shark probably followed prey through Sydney Harbour and into the river.
“I don’t think it was sick. It was in a clean waterway with lots of food,” he said yesterday.
“It was clearly still feeding when it was caught.”
Harcourt says mako sharks feed on squid and fish in the open ocean during summer, but during winter come closer to the coast in search of mullet.
The mako’s presence shows the harbour and river system are healthy enough to sustain large amounts of fish, Harcourt said.
“It’s salt water, it’s full of fish, plenty of bream that’s why people fish in it,” he said.
“It’s a good sign for the harbour. It’s unusual, but not amazingly strange.”
Makos might be “unusual” but bull sharks are common in the river.
“We get bull sharks right through the summer,” Harcourt said.
“There are a lot of them and they’re a big shark.”
Melograna initially thought he had snared a bull shark. AAP