reporter: climbing up rock piles, looking through disregarded metal. nothing? nothing. reporter: so, you think, though, this is a pretty good day to find snakes, right? this should be a textbook day. it s nice and sunny. reporter: apparently, the pythons didn t read the book. we even tried at night. a nice, beautiful little snake. yep. reporter: a native species, not a threat. we also went out twice with joe, the wildlife biologist, walked miles of prime snake country. not a single snake in the grass. just oh, my god. slow, it s a gator. a big gator over here. reporter: how long is he? oh, he s a good ten foot. reporter: he s a good size. so what happened to all the pythons? we are thrilled that the weather was so cold in south florida this year that it may have killed 40% to 50% of those reptiles of concern. reporter: that may be conservative. the pythons simply couldn t
i always tell everybody, it s like trying to find a needle in the haystack when looking for the snakes. reporter: and the everglades is one big haystack. josh hunts pythons. we ve been out with him twice slogging through the glades. look at this mud we re going through now. reporter: climbing on rock piles, looking through disregarded metal. nothing? nothing. reporter: so you think this is a pretty good day to find snakes, right? this should be a textbook day. it s nice and sunny. reporter: apparently, the pythons didn t read the book. we even tried at night. a nice, beautiful little snake. reporter: a native species, not a threat. we also went out with joe, the wildlife biologist. we walked miles of country, not a single snake in the grass. just oh, my god. slow, it s a gator. a big gator over here. reporter: how long is he? oh, he s a good ten foot. reporter: he s a good size.