| 1 | Brazilian smooth snake |
Maximum length: 3 metres.
A cannibalistic snake of southern Brazil, Argentina and Paraguay. This large species is so notorious for eating its fellow kind that reptile keepers warn beginners never to keep them in the same cage.
The Brazilian smooth snake (Hydrodynastes gigas) is a semi-aquatic species, which mainly appears in rivers, wetlands, marshes and swamps. This species isn’t passionate about cannibalism, and doesn’t conduct chanting rituals in caves like humans. The main reason is that this species is ruthless, and will eat virtually anything in order to survive.
Brazilian smooth snakes have a dietary breakdown of 30-40% amphibians, followed by reptiles and other snakes at 20-30%. They have a mild venom suitable for subduing small prey, and also prey on snakes such as the leopard keelback and golden liophis.
The Brazilian smooth snake rolls forward like a tank and swallows its kin without thinking. They pose little threat to human beings, despite measuring 2-3 metres, but can bite painfully if repeatedly bothered. Another of their skills is playing dead; in fact, they’re one of the largest-death faking snakes on Earth (most are smaller).
| 2 | Puerto Rican boa |
Maximum length: 241cm (at least).
The Puerto Rican boa is benign in most ways, with no venom and a docile personality. Their one dark secret is committing the grotesque act of cannibalism. In 2004, scientists witnessed an adult measuring 100-150cm swallow up a juvenile measuring 50cm, in a karst valley floor. The boa swallowed its kin by the head and was one quarter swallowed when the scientists first appeared. They published their findings in Herpetological Review.
The Puerto Rican boa lives solely in its namesake islands, particularly in karst cave regions. They move at moderate speeds, but occasionally accelerate in sudden bursts. Other confirmed prey include fruit bats, black rats, and Evermann’s anoles.
One reason for their cannibalism is that snakes have no protective instincts. Social animals such as humans or a herd of sheep have a natural instinct to protect each other. This isn’t necessarily intelligence-based, but using animal instinct, recognising a creature that looks like them.
Meanwhile, snakes couldn’t care less about their fellows (with a handful of exceptions). They’re solitary creatures, and keeping a smaller, weaker snake alive doesn’t factor into their thinking. If possible, they’d rather eat them.
| 3 | Chilean long-tailed snake |
Maximum length: 220cm.
This Chilean snake has no qualms about eating its fellow kind whatsoever. In 2018, scientists witnessed its cannibalistic ways first hand. They were walking past a small stream in Chile’s Valparaiso Region, when they saw a fully grown Chilean long-tailed snake swallowing a smaller one.
60 minutes later, the swallowing was almost complete, but the snake was spooked by the scientists, and regurgitated its smaller meal. Miraculously, it was still alive, and the two continued to duel, before fleeing in opposite directions.
This species lives both in forests and grassland, and primarily eats lizards, adding mammals as they gain size. When committing cannibalism, their hunting style is identical to usual. The Chilean-long tailed snake moves steadily behind resting prey, gaining centimetre by centimetre. They’re immensely patient, and only pounce when they’re within virtually infallible range.
Philodryas chamissonis both slithers along the ground and zips along tree branches manically, and is mainly active at night. This species is found solely in Chile, and often invades people’s houses.
| 4 | Cyprus black whip snake |
Maximum length: 250cm.
The 2 metre black whipsnake (Dolichophis jugularis) is one of the most common snakes in Cyprus, Israel and Lebanon. They’re everywhere in certain stony fields, and apparently they’ve decided that there’s no risk in eating each other, just a little bit.
Black whipsnakes are completely non-venomous, and farmers used to trade them in olden times, for their beneficial effects on rodent populations. As well as black rats, goldfinches and snake-eyed lizards, black whipsnakes are confirmed to eat each other, for a helping of protein and nutrients like zinc.
It’s unlikely that fellow species members have any special nutritional advantage (even if they’re built with the exact same nutrients). Snakes are creatures of convenience, and even though they don’t all stoop to cannibalism, they’ll always take an easy meal rather than one which takes effort. If they don’t take easy sources of calories when they can, they’ll be outcompeted by more ruthless snakes nearby.
Black whipsnakes have never killed a human, but are extremely aggressive, producing an intimidating hiss and gaping their mouths widely. One of their characteristics is an ontogenetic colour change, as they grow steadily blacker and blacker with age.
| 5 | Smooth snake |
Maximum length: 92cm.
The smooth snake lives in British heathland, and derives most of its calories from native reptiles like slow worms and common lizards. Occasionally, this needs supplementation, and the smooth snake (Coronella austriaca) makes the easy decision to swallow up its fellow kind.
Smooth snakes use a hybrid hunting style, combining pursuit and ambush. They position themselves in tangled heath strands, and follow their prey after they stroll past rather than instantly pouncing. The main determiner of prey is accessibility, not species, and consequently, smooth snakes have no problem with mindless swallowing each other.
The smooth snake would probably commit cannibalism if it was one of the last 2 individuals of its species on Earth. Even if they were stranded in one tiny heathland patch which was about to be removed in a controlled wildfire, they would probably slither over and eat each other without thinking.
This species can live nearly 30 years, and thanks to its mid-ranking place in the food chain, it is regularly gobbled up by pheasants, foxes and badgers.
| 6 | Mulga snake |
Maximum length: 3.3 metres.
The mulga is already a brutal snake, injecting 400mg of venom per bite and charging at victims in a wild rage. So cannibalism probably feels like nothing special, as they delve ever further into the dark arts.
Mulgas, AKA king brown snakes, are the longest venomous snake in Australia, and have a very wide diet. They eat geckos, skinks and mammals, and prey on crowned snakes as well as cannibalising each other.
A mulga snake could swallow a black-headed snake, and seconds later be swallowed by an even bigger mulga. This species has multiple observations of it eating its own kind. Mulgas are even known to eat roadkill and the shed skins of fellow reptiles.
Mulgas don’t shy away from interspecies aggression in general, as males are constantly wrestling, intertwining their necks with all sinews straining. These battles can last for 2 hours, with nothing but dust on the horizon. Mulga snakes also invade human towns, particularly Alice Springs, where they lunge at unsuspecting people as they stow their bicycles away. If we’re lucky, they might eat every last one of each other.
| 7 | Montpellier snake |
Maximum length: 216.2cm.
This mildly venomous snake devours all in its path, including wood mice, Algerian sand racers and European rabbits. Cannibalism is the next logical step, one which it gladly takes. Montpellier snakes live in Spain and Portugal, where they’re the longest native snake, regularly exceeding 2 metres. They’re a confident and adventurous species, moving around freely in full view.
The Montpellier snake has a no holds barred, anything goes philosophy, and this extends to eating members of its own species. They’re willing to try anything once, or maybe dozens of times if they enjoy it.
It isn’t as though Montpellier snakes are unable to recognise each other, as their scent apparatus is far more sophisticated than a human’s. Snakes need scent particles to identify each other when breeding. They simply consider belonging to the same species to be irrelevant, and gobble down their meal with enthusiasm.
Another disturbing possibility is that cannibalistic snakes are more attuned to their fellow species members, making them easier to hunt. The Montpellier snake licks its lips, and slithers off for a meal which is virtually impossible to miss.
| 8 | Western Galapagos racer |
Maximum length: 128.5cm.
This species faces endless predators on its namesake island, including owls, centipedes and mockingbirds. Worst of all, even their own species wants to eat them. Nor can they complain, as western Galapagos racers (Pseudalsophis occidentalis) regularly give in to the temptations of cannibalism themselves.
This species occurs solely on the Galapagos Islands, and primarily feeds on reptiles, such as Galápagos leaf-toed geckos and Isabela lava lizards. Most of their lives are spent on the ground, following subtle scent trails.
Though not forming a large portion of their diet, Galapagos racers were proven in 2021 to eat each other, in a study examining 93 racers captured at Cape Douglas, Fernandina Island. If a fellow species member catches its eye and is in a strategic location, then the Galapagos racer will slither up and swallow it whole, with no loyalty whatsoever.
This species lives in arid shrubland and deciduous woodlands, which makes fulfilling their cannibalistic fantasies all the more easy, giving them cover to advance and burst forward at the very last second. Galapagos racers live in relatively isolated locations, and scientists are only just uncovering their secrets.
| 9 | New Guinea small-eyed snake |
Maximum length: 2.1 metres.
The New Guinea small-eyed snake (Micropechis ikaheca) either doesn’t realise that it’s eating fellow members of its species, or just doesn’t care. This cannibalistic snake lives in deep parts of the world, which appear in low detail on maps, and are only under tenuous control by mankind.
Such places are home to the more extreme elements of nature, and Micropechis ikaheca fulfils this by swallowing members of its own species whole. They’re found in New Guinea and nearby islands like Karkam Island, in low-lying marshes and forests, sometimes beneath piles of coconut husks.
This species unhinges its jaws wide, starts with the head, and waits until the snake is completely swallowed before beginning the digestion process. This cannibalistic meal can sustain them for weeks, until their snake hunger hormones start cranking back up again.
New Guinea small-eyed snakes are aggressive, and a bite to a human thumb can kill within 36 hours. They’re flexible rather than restricted to one dietary niche, feeding on frogs, lizards and mammals alike. They appear in both halves of the island: Indonesia to the west and Papua New Guinea to the east.
| 10 | California kingsnake |
Maximum length: 142.2cm (2 metres on certain islands).
The California kingsnake (Lampropeltis californiae) is a species of the southwestern US, inhabiting mainly open areas such as grassland or dry plains. They have no venom and are little threat to humans, killing their prey via grappling and pinning.
This species already has a taste for other snakes, as long as they can slot neatly into its belly. Their hunger is all-consuming, and fellow species members don’t escape its roving eye.
California kingsnakes have been spotted eating gopher snakes, sidewinders and Pacific rattlesnakes, so they have no preference for eating each other, but nor do they have a problem with it. They swallow their snake prey by the head, slotting them neatly into their own elongated body. They mainly move by day, and are active foragers rather than ambushers.
California kingsnakes generally aim for species members smaller than themselves, out of simple convenience. It’s easier to cannibalise snakes smaller and weaker than themselves – that’s one of nature’s brutal laws. Supposedly, kingsnakes will even try to eat themselves if hungry enough.