Fishers off South Australia’s south-east coast have been treated to a spectacular sight, with thousands of salmon surfacing to feed.

Bordertown resident Leah Bailey was fishing at Cape Jaffa, near Kingston SE, when she came across the salmon.

“We found the school and they were all under the water … and we were casting at them and we were catching a few off of the boat,” she said.

“In a matter of seconds they stopped on the bite … and they just all came straight to the surface and started feeding.

“Even what we were casting was way too big, they were just not interested in us at all.”

Thousands of salmon took part in the feeding frenzy.(Supplied: Leah Bailey)

Drone captures frenzy

A keen photographer, Ms Bailey managed to capture the feeding frenzy from above using her drone.

“It was definitely a one off thing for me, and I was very lucky to have my drone on me,” she said.

“There were hundreds or thousands – seriously they were everywhere.

“Even the drone footage doesn’t show half of what was there.”

The vision quickly attracted interest after it was shared on social media earlier this month.

“It’s been crazy, I didn’t think it would get that much attention to be honest,” Ms Bailey said.

“I love everyone’s comments on how they said they still wouldn’t be able to catch a fish with so many around.”

Cape Jaffa is a popular spot for recreational and commercial fishing.(ABC South East SA: Eugene Boisvert)

Rare sight for locals

Local boat tour operator and former professional fisherman Scott Gluyas said it had been a “long time” since he had seen salmon feeding in large numbers in the area.

“I used to do a little bit of fishing down the Coorong, and it happens there quite often,” he said.

“The salmon’s been really handy for all our local recreational fisherman around here.

“They seem to be getting their hands on a nice bit of fresh bait every day they go out around the Cape Jaffa area.”

Mr Gluyas said it was reasonably common to see salmon at this time of year, but not in such large numbers.

“They don’t often come to the top like that, that’s for sure,” he said.

The Bonney upwelling attracts marine animals along the coast from the South East to Portland, Victoria.(Supplied: Blue Whale Study)

Upwelling attracting salmon

Fishers are attributing the frenzy to the Bonney upwelling – a naturally occurring system that brings cold and nutrient-rich water to the surface.

As the water upwells, phytoplankton also come to the surface which feed krill, in turn attracting a range of marine life – including dolphins and whales.

Mr Gluyas said the cold water had impacted on recreational fishers, with species such as snapper hard to come by.

“Because of the upwelling that we’ve had and all of the plankton … everyone is saying the same story about salmon, and a few whiting have been about what’s been on the menu,” he said.

“[The upwelling] has been off and on for most of the year, but luckily it hasn’t affected the crayfish that much.”

Ms Bailey said she had experienced similar issues.

“We’ve had a fair bit of trouble with the temperatures of the water,” she said.

“It’s been pretty cold so there’s not as much coming up to surface to feed.

“But on the good days when we have a good fish, then we do get a few.”

The impact of the Bonney upwelling typically begins to decline in April.

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