Cow heart baits my hook and it's piranha I hunt.
The prey could be snapper, given the happy laughter and joking of the locals. But we tourists know better, being reliably informed by childhood cartoons of the piranha's ferocious ability to scythe through anything in seconds, animal or not.
Other creatures such as anaconda inhabit the waters surrounding our lodge, in Brazil's Mato Grosso and amid the vast Pantanal - the world's biggest wetland that, incredibly, covers an area almost the size of Great Britain, and is 20 times the size of Florida's Everglades.
There are no worries about scaring the fish away here - a favoured method is to furiously splash the water's surface before dropping the line.
Our group is soon joined by another fisherman, but, despite the obvious bad manners, nobody is going to tell him to move on and find his own spot.
A caiman - one of hundreds of the alligator-like reptiles in the area - watches our progress with two blowflies resting on the island that is the top of its head. It waits expectantly, like a spoiled dog by the table.
Hooks come up empty several times before, to the displeasure of the Kiwis present, an Australian travel writer lands the fearsome catch.
Actually, the fish looks harmless and isn't much bigger than the palm of my hand.
In reality, piranha and caiman have more to fear from humans - later in the day our boat passes an upturned and bloated caiman corpse, its tail chopped off to fill a local's pot (an illegal practice but one that continues).
As for the piranha, at our lodge, Pousada Rio Mutum Pantanal, in the municipality of Melgaco Baron, the fish are served up in a stew each night along with a buffet.
The taste is hardly detectable among the other ingredients, but that might not be the point - piranha stew is known as an aphrodisiac nicknamed "Pantanal Viagra".
I can report no effects, but my companions' conversation soon turns from movies on the flight over to comparing the dancing and other merits of Magic Mike II's cast.
Although piranha fishing makes for good stories, the real reason people come here is the wildlife which, without dense jungle, is easier to spot than in the more famed Amazon.
Low lands covering 210,000 sq km, the Pantanal has Amazon and savannah vegetation, giving rise to incredible diversity - 2000 plant species, 600 birds (including 100 in the lodge's surrounds) and nearly 100 mammals.
A Brazilian Government relocation programme in the 1970s led to massive deforestation for soybean farming, but the Pantanal, which crosses into Bolivia and Paraguay, was largely protected by prodigious rainfall and flooding each wet season.
The lodge is a two-and-a-half-hour drive from the city of Cuiaba, which is in the exact centre of South America, and the red earth road passes under big sky and alongside cattle ranches dotted with hundreds of waist-high termite mounds.
(On the drive out we spot an anteater slowly making its way among the grey, imperfect cones).
Hiking and horse-riding is on offer at Mutum, but the main activity is boat tours, through the surrounding rivers and across lakes, Baia Chacorore and Baia de Sia Mariana.
Much of the wildlife comes to the front door. On our last night there's a commotion during dinner and we head outside to see, illuminated by the torch of a guide, a beast that looks like a large pig with a badly stunted elephant trunk.
The tapir, attracted by fruit dropped from the towering mango trees that dot the lodge's sprawling grounds, happily munches away, ignoring the audience.
Our visit comes soon after the start of the rainy season, and the biting mosquitoes are out in full force.
Sanctuary can be found in the lodge's swimming pool, but hammocks and chairs in its sprawling grounds look almost comically hopeful.
Once on the boat, the blood-suckers become less of an issue, but two clothing layers are still advisable - my shoulders are covered in welts after one trip - the singlet under my long-sleeved shirt proving the difference.
Thankfully, there's more than enough distraction.
We spot red-legged ibis, southern screamers (think exotic turkey), three types of kingfisher, zigzag and cocai heron, jacana, and more, all in one morning tour.
The frequency as much as the variety astounds, and every 10m the boat slows and Natalie, our guide and qualified botanist, points out another animal.
At one point a group of sleeping bats are startled, and a dozen flap around and above the boat. Only mouse-sized, they seem more like butterflies.
There are dozens of capybara. Growing up to 75kg, the animals are the largest rodents in the world, and look like over-sized guinea pigs.
Feeding on vegetation, the capybara are dopily unfussed about the boat, eyes narrowed like a cat's in the sun.
At one clearing, 12 capybara, including several puppy-sized babies, sit as if in congress with a single white egret.
Agreement reached, the rodents swim away in single file, heads and great, cartoonish snouts above the reddish water.
Small capuchin monkeys come to check us out, and we spot a larger howler monkey. Puma and jaguar roam the Pantanal, but are rarely sighted.
The Pantanal delivers a huge roll call of critters, but my standout comes after a clicking and squealing noise, not unlike the noise from a child's squeezey toy, is tracked to bright green vegetation on the river's edge.
The racket is from baby giant otters. Pushed to extinction in other areas of South America, six adults have made their home not far down river from the lodge - a hole in the bank the only clue as to the tunnels within.
The babies stay hidden, but the adults, which can grow up to a whopping 1.8m in length, poke their head above water.
Their peach-coloured mouths hang open as air is noisily gulped in, before dipping down and resurfacing about 10m away.
As one surfaces and dives another repeats the pattern, like dolphins cresting in the same direction, and it becomes clear they are fishing.
The otters disappear and the river quiets, its water reflecting the twilight sky.
Then, the loud crunch of fish bones and flesh, a noise that a newcomer could attribute only to the river itself.
LAN Airlines operates seven non-stop flights each week from Auckland to Santiago, with onward connections to Cuiaba. Economy fares are on sale until April 11 for $1785.09.
Eclipse Travel run a 12-day Explorers Route itinerary that takes travellers between Buenos Aires and Rio via Iguazu Falls and the Pantanal wetlands. Fares start from $4470pp and include accommodation, internal flights and English-speaking guides.