This episode is about the biggest snakes in the world! Don't worry, it's not creepy. Snakes are neato!

Welcome to the Patreon bonus episode for Strange Animals Podcast for the first of September 2017.

The biggest snake that ever existed was Titanoboa. It lived in South America some 58 million years ago and its fossils were only discovered about 20 years ago and not recognized as snake fossils until around ten years ago. The fossils have all been found in Colombia, in areas that have been strip-mined for coal.

58 million years ago the area was a hot, swampy, tropical forest. Now it’s a baking field of rock uncovered by mining, which is not good for the environment but it’s unbelievably good for palaeontology.

The experts who first discovered the fossils didn’t believe they were snake vertebrae at first. They were just too big compared to every other known snake skeleton. Careful estimations of the snake’s size compared to modern anacondas and boas, its closest living relatives, were published in Nature in 2009.

Titanoboa probably grew from around 40 to 50 feet long [12 to 15 meters], and could weigh more than 2500 pounds. That’s one and a quarter tons, or more than 1100 kg. The thickest part of its body would have been waist-high compared to an average human male.

But what about living snakes? Reticulated pythons from Asia are considered the longest living snakes, while green anacondas, also called common anacondas, or green pythons in older accounts, from South America, are generally considered the heaviest and probably the second longest snakes.

Pythons, anacondas, and boas are all constrictors, the kind of snakes that don’t bite their prey, they just wrap around them and use their muscular bodies to stop their prey from being able to take breaths. After its prey suffocates, the snake unhinges its lower jaw to enlarge its throat, which allows it to swallow its prey whole. It can take days or even weeks to digest its prey, during which time the snake will basically just laze around being all chill, the way I do after Thanksgiving dinner.

According to the Guinness Book of World Records, the longest captive snake ever reliably measured is a reticulated python named Medusa. In 2011 she was 25 feet 2 inches long [7.68 m]. I can’t find a more recent measurement of her. The average reticulated python is between ten and twenty feet long [3 to 6 m]. Medusa was ten years old at the time of her measuring and weighed 350 pounds [159 kg].

In 2016, a python captured in Malaysia when it showed up on a building site supposedly measured 8 meters, or over 26 feet, and weighed 550 pounds [249 kg]. Unfortunately, the capture wasn’t humane and the snake died three days later after giving birth prematurely.

Look, be nice to snakes, everyone. They’re really not going to hurt you if they can possibly help it. I’ve got scars on my body from dog bites, cat bites, and a sheep that butted me into a fence, but I’ve never been harmed by a snake—and yes, I have handled them pretty often. Most species of snake literally couldn’t hurt you if they tried.

Anyway, there have been lots of reports of ridiculously enormous snakes spotted in the wild. In 1912, a reticulated python shot in Indonesia supposedly measured almost 33 feet [10 m]. In 1906, British adventurer Percy Fawcett claimed he’d shot an anaconda that measured just over 62 feet [19 m]. A 2003 report of a 49-foot [15 m] reticulated python in captivity in Indonesia turned out to measure only around 21 feet [6.4 m] when reporters showed up with a tape measure.

The problem with measuring dead snakes is that snakes are really stretchy. They’re even stretchy when they’re alive. That goes extra for shed snake skins, which are not good indicators of the live snake’s length since they often stretch quite a bit as the snake wriggles its way out of the skin. I used to have a garter snake living in my yard, and I know its length was not much more than a foot [31 cm] because I saw it a lot—and in fact one day it fell on my head when I opened the garage door. But its shed skins looked close to twice as long, and were so difficult to untangle from the rose of Sharon branches where it liked to shed that I never could get a good measurement anyway.

Venomous snakes are much smaller than constrictors, although frankly I’d rather not tangle with any of them. The king cobra is considered the longest venomous snake, with verified lengths of nearly 19 feet [5.8 m]. The heaviest venomous snake may be the eastern diamondback rattlesnake, the Gaboon viper, or the king cobra, all of which weigh in at less than 50 lbs, or around 20 kg. When you have to stick your fangs into prey to kill it, you’re going to be a lot more lithe and agile than if you just drop on your prey from tree branches and squeeze.

If you do an image search for huge snakes, you’re going to get a whole bunch of faked pictures. In 2012, pictures of a supposedly 98 foot long snake [30 m] supposedly killed in North Carolina, went viral. But the pictures are actually from Indonesia, and the snake pictured is probably around 20 feet long [6 m]. As I was researching this episode, I kept running across those same photos in different articles. One site insisted the snake was a 33 foot long [10 m] anaconda killed in Brazil, when it’s clearly a reticulated python, although I’ve also seen other pictures attached to the 33 foot long anaconda killed in Brazil story, so some reporter somewhere probably just got confused. Also, the anaconda was not 33 feet long.

Similarly, a picture of a 22 foot long [6.7 m] green anaconda in a river went viral in summer of 2016 when someone posted it as a photo taken in South Carolina’s Broad River. In fact the photo is from South America.

Occasionally an exotic snake really is caught in the Carolinas, but winters get colder there and tropical snakes are not able to establish breeding populations the way they do in Florida. In May of 2016 a redtailed boa was caught in Matthews, North Carolina. Fortunately for the snake, in this case she was caught by two biologists who happened to be hiking in the woods, and they turned her over to Carolina Waterfowl Rescue. She was a lot luckier than another redtailed boa, who measured eight and a half feet [2.6 m], which was accidentally killed by utility workers in 2015 in Greeneville, North Carolina.

We do have some big snakes in North America, but the native snakes are all much smaller than reticulated pythons and green anacondas, and their relations. The black rat snake is probably the longest North American snake. It’s also called the western ratsnake. It’s generally gray or black without markings. It’s non-venomous and harmless to humans, and mostly eats rats and mice, although it will also eat squirrels, birds, frogs, and other snakes when it can catch them. It can grow to eight feet long [2.4 m] and I’ve seen individuals near my home that are easily four feet long [1.2 m]. The eastern diamondback rattlesnake can grow up to seven feet long [2 m], but it’s shy and despite hiking extensively in snakey areas, I’ve never once seen one. (Your mileage may vary. Just be careful.)

Unfortunately, people keep various species of python and anaconda and boa as pets, and sometimes those pets are released or just escape. When this happens in Florida, the snakes can survive and even thrive in the subtropical climate. A new program in Florida started in March of 2017 has authorized bounties for invasive snake species, and some real monsters have been caught. A nearly 17 foot [5 m] python was caught in May in the Everglades, and in April a Burmese python nearly 15 feet long [4.5 m] was caught. The longest exotic snake ever caught in Florida was a Burmese python that was 17 and a half feet long [5.3 m] and weighed 165 lbs [75 kg].

Not only do non-native snake species eat pet dogs and cats, they’re incredibly damaging to native bird and mammal populations. Pythons have been found in the Everglades since 1979, but the biggest damage was done in 1992. A breeding facility for Burmese pythons was destroyed during Hurricane Andrew, and many of the snakes escaped. By 2000 the Burmese python was determined to be established as a breeding population. They have no natural predators and have become and apex predator in the Everglades, nearly wiping out some species of birds and mammals. State law now bans people from owning Burmese pythons and certain other snake species as pets, and you can’t even transport them across state lines without a Federal permit. (But it’s kind of a little bit too little too late.)

There may very well be individual snakes out there that are several feet longer than the known maximum length for their species, but in general I’d be wary of anyone who claims to have measured a snake exceeding around 30 feet in length [9.1 m], especially if they don’t have reliable witnesses, proof, and preferably the live specimen to be measured again by snake experts. Even Titanoboa, the biggest known snake to ever live, probably didn’t grow more than fifty feet long [15.25 m], if that.

But honestly, why do we need to believe there are 100 foot long snakes hidden in the depths of the Amazon or wherever? A 25 foot snake [7.6 m] is really, really big! Celebrate the snakes we do have, because they’re definitely awesome!

Thanks for your support, and thanks for listening!