When it comes to seeking -- Brazil's most. Fascinating creatures the Amazon jungle has a way of stealing the spotlight. But some giant snakes too elusive big cats -- man is out to prove other parts of... See More
When it comes to seeking -- Brazil's most. Fascinating creatures the Amazon jungle has a way of stealing the spotlight. But some giant snakes too elusive big cats -- man is out to prove other parts of the country have just as much to offer an ABC's -- document went to see for himself. Brazil's Amazon and it's Nebraska's sized whether it's called the -- and now I'm proud by nature's most. -- -- -- -- -- Crocodile like came -- -- Good -- HC special kind of man to love it love it 150. Pound -- It is the biggest Robbins on -- the company Mara and that man is -- swab. And they have via the honor of being the favorite food of joggers and and -- -- -- Largest -- -- corner of the century building wildlife here. The perpetually enthusiastic naturalist had already showed -- one side of Brazil a couple of months ago. Yeah. Yeah. It's unparalleled swim with one of the world's biggest snakes. On now -- on a mission to prove there's more to Brazil could bring. Joked he's agreed to show Nightline his most prized and most secret spots. Getting there -- not easy. There's no tarmac here it's just dirt and some grass. We transfer to these little -- hold skips and spend hours exploring. Black vultures. Dancing -- carcass and likely that was a -- -- -- came. Ten times the size of Florida's Everglades the -- -- -- is the world's largest freshwater wetland. Home to the largest concentration of wildly in the Americas including its biggest can't. Jaguar if it's your job for the maker -- bake off and not move. Because if we weren't -- fanning -- and we are pretty. So we would not never ever run yet you don't want to end up like this copy or this came -- the -- captured one of the ravens jaguars -- ever feel. Imagine an animal that has just trying to break your neck before -- -- can't -- blue -- -- This latest -- that. This is -- is world -- he documented secret Brazil but they shot today GO shows that would prevent seconds. Agonizing months to capture I've spent up to seven hours watching the state animal teaching and that. On to his next favorites but this time to Brazil's Savannah. At dusk we roll out scouting for one of -- his favorites the giant -- eater. Just moved -- -- season. Can face and got what when his stand up and open the club's job -- who -- But -- best defense is always liked the widow of flight school provisions is that it was -- -- aggressive. Dusty but satisfied. -- -- -- a report. A -- I'm talking about this tipped off and you won't be his appointment. It is as a -- Moody till spring so -- and they say visibility is hundred feet you can. I admit I was not a believer but now we have been baptized -- beauty. -- -- -- -- It looks like its -- -- one of those -- screen savers and an LCD screen but yeah. That's why they look like all right but your face -- and -- look as if there's a -- just doesn't look real. It's a good witness Lawrence while -- secret Brazil. I'm Matt Gutman for Nightline in western Brazil. Moon just gorgeous secret Brazil airs Sunday January 20 on Nat geo while.
This transcript has been automatically generated and may not be 100% accurate.