Like most good ideas, the annual barramundi fishing competition Secret Women's Business was cooked up by two enterprising women after a few drinks.

"This concept came about 11 years ago. Two ladies were having a couple of glasses of wine and decided they wanted to start a fishing competition just for women," event organiser Chrissie Hurren said.

"Initially that was the goal, to challenge the male-dominated sport of fishing."

Over a decade later, this year's competition features 119 women across 36 teams on the Corroborree Billabong, about 90 minutes drive south-west of Darwin, all competing to see who can get the biggest bite.

The women, rated from novices to experts, angle for barramundi and saratoga over two days, with barramundi worth double the points, and any caught are tagged to assist with Department of Fisheries research.

All fish are tossed back once points are tallied, and there is $20,000 worth of prizes up for grabs.

"It's an environmental issue, there are a lot of teams on the water fishing today and if all of them removed the fish they caught that would have a detrimental effect on fish stocks," Ms Hurren said.

Some women may be catching their first barra this weekend, which she said was an immense adrenaline rush.

"It's amazing... it's really exciting, and when you land it, it's fantastic," she said.

Chrissie Hurren, an organiser of the Secret Women's Business fishing competition in the NT. ( ABC News: Jano Gibson )

'We just fish alongside the guys'

In the pre-dawn dark, trailers back boats into the billabong.

As the sun begins to rise, the singing of birds and the chirping of insects are interrupted by boat motors as women zip along the water in the foggy morning light, looking for fish.

In the Barralicious boat (the 'i's dotted with love hearts), two women wearing pink hoodies, gloves, scarves and socks steer alongside thatches of lily pads near the banks.

"We took out the Ugly Barmaid Award last night, we're killing it already!" they joke. But so far, nothing's biting.

Over on the Bad Habit boat, the Sister Act team are having similarly bad luck.

The women are hoping to reel in some barramundi over the weekend. ( ABC News: James Bennett )

Luckily for Tina Moyle, the competition is as much about the camaraderie as the catch.

"It's about getting away with these ladies, we have a good time on the water," she said.

"SWB was initially about becoming a fisherman in our own right, so I think that competition plays a big part in women's finishing today in a safe environment."

But she said women no longer needed to prove themselves in a male-dominated sport.

"Not at all, we just fish alongside the guys; we've got our own boat, we do everything ourselves," she said.

"It makes fishing easier when you do go out with your partner, they don't have to do anything for you, you don't do anything for them!" she laughed.

'Any bad day fishing is better than a good day working'

Jennifer Wilson (L) and Rocky Edwards (R) on team Wilson Fanatics' boat. ( ABC News: Jano Gibson )

Wilson's Fanatics were also struggling to get a bite.

"We've tried absolutely everything you can think of, we've thrown the book at this billabong, and it is very slow," Rocky Edwards said.

"We have caught fish, but they are undersized so they're not scoring. So we just have to keep at it and persist and hope we catch some scoring fish."

She said she loved being part of an all-female crew.

"It is really good to do it on our own," she said.

Teammate Jennifer Wilson, from Queensland, was philosophical about their prospects.

"It's fantastic, where else would you rather be?" she said.

"The fishing's a bit slow, everything we've caught has been undersized, but any bad day fishing is better than a good day working, that old chestnut."

The competition will wrap up on Saturday afternoon.