| 1 | Green mamba |
The black mamba’s cousin, which inhabits coastal southeastern Africa, and spends vastly more time in trees. Green mambas have speed when they need it, with a lightning strike and blinding lunge for bird prey. But unlike the twitchy black mamba, they’d much rather drape themselves peacefully over a branch all day. Their green colours make them tricky to spot for people wandering below, despite an average length of 1.5 metres.
Green mambas specifically choose areas of thickly overlapping branches, to create a protective cloak of foliage they can vanish into. They have a regular daily cycle: begin on high branches, shift a few metres downwards for an active ambush session, then retreat to the safety of the canopy later in the day. Every so often, they embark upon a longer migration to a fresh tree.
Because of their tree-dwelling lifestyle, bites are far rarer than with black mambas. Their venom contains the usual alpha-neurotoxins responsible for laboured breathing, but virtually no deaths have been recorded. The green mamba’s love of trees is reflected in its diet. Black mambas eat 81.5% mammals and 18.5% birds, but this ratio shifts towards birds in green mambas, at 42% versus 58% for mammals.
| 2 | Madagascan cat-eyed snake |
Madagascar’s main tree snake. This is a thin-bodied species which weaves down thin branches, and rapidly accelerates if necessary. They average at 90-100cm, and inhabit most of Madagascar, from north to south. Rather than green camouflage, they rely on speed and nimble acrobatics for their survival. This snake varies from brown to yellow to silver.
Rather than deep rainforests, common Madagascar cat-eyed snakes are happy in degraded human zones. As long as tree clumps are standing, they can survive and thrive. They appear in trees in villages, gardens, outside town halls, near cocoa plantations. Building your dream house by a forest gives them a corridor directly to your bedroom windowsill.
Madagascarophis colubrinus drops to the ground when necessary, but they’re most at home on tree branches, where every aspect of their body is fine tuned. They’re capable of stalking and grabbing prey on branches, including chameleons and hatchling birds. Madagascar cat-eyed snakes have a supposedly mild venom, which nevertheless contains a neurotoxin called maculotoxin, discovered just last year (2023). However, the chances of being bitten are extremely low.
| 3 | Mexican parrot snake |
Part of the 19-member Leptophis family, the most common being the giant parrot snake. Mexican parrot snakes (Leptophis mexicanus) live from eastern Mexico to northwest Costa Rica, inhabiting 7 countries overall. While only mildly venomous, parrot snakes are infamous for their crazed facial expressions as they gape their mouths open wildly while trying to intimidate people. As a branch-dwelling snake, their demented face could be just inches from yours.
Mexican parrot snakes spend most of their day on branches, preferring moderately high perches rather than low bushes or 20 metres high. They prey on iguanas and anoles, and fully exploit their arboreal environments, investigating crevices in tree trunks for lurking prey. Mexican parrot snakes are completely familiar with their home tree, and know instantly when anything is inconsistent.
Guatemala has over 130 snake species, while Costa Rica has over 135. Flexible as snakes are, there’s no way they can all coexist in the same habitats without destroying each other. Consequently, Mexican parrot snakes have taken to branches to avoid the bushmasters and lanceheads prowling around below. Even here, they face competition from the likes of Imantodes tree snakes.
| 4 | Blunt-headed tree snake |
Its adaptions are manifold. There’s sharply angled scales to dig into tree trunks, and bulbous eyes to scan every inch of the forest. Their body is compressed, adding length without making them heavier, allowing Imantodes cenchoa to cross the thinnest of branches. For some reason, their neck is extremely thin. Imantodes cenchoa mainly preys on rainforest lizards, including bridled anoles, pug-faced anoles and border anoles.
Blunt-headed tree snakes know their world inside out. They’ve been found in coffee trees and will lurk calmly between two enormous overlapping rainforest laves, to grant them camouflage. Imantodes cenchoa is particularly attracted to bromeliads, members of the pineapple family, with tightly packed spirally leaves and a bowl at their centre. They rest in these bowls while they steadily fill with rainwater, taking occasional mouthfuls.
| 5 | Ruschenberg’s tree boa |
A relative of the Amazon tree boa, ringed tree boa, etc. This species is particularly common on Trinidad, where it hisses at people from eye level, specifically on a tree branch perch. This is a non-venomous constrictor which crosses open ground if necessary to find a more bountiful ambush site, but prefers to stay in trees all day, whether at mid-height or 10 metres high in the canopies. Corallus ruschenbergii is encountered regularly by Trinidad locals, who dub it “dormillion”.
As a nocturnal snake, Ruschenberg’s tree boa can be tricky to spot, but there’s a great secret – their eyes reflect torchlight incredibly well. This is a trait found in most Corallus tree boas. Scan around with your handheld light beam and a pair of glowing white coins may appear in a tree, side by side, followed by a hissing serpent, followed by an open mouth, followed by an inside view of a snake’s stomach (ignore that last part).
Ruschenberg’s tree boas measure up to 2 metres and are relatively thin for a constrictor, to balance effectively on branches. This tree snake mainly preys on rodents.
| 6 | Bird snake (Africa) |
An African tree snake measuring up to 1.8 metres. Bird snakes (Thelatornis kirtlandii) are common in West Africa, including Ivory Coast, Ghana and Nigeria, and appear as far east as Uganda.
This species has caused one confirmed death, in an 80 year old woman who suffered kidney failure. Its diet is nearly entirely lizards, with 39 reptiles found in adults versus 1 amphibian and 1 bird (and no mammals). These diet and venom discoveries were more recent, whereas one fact was always certain: that bird snakes love trees. A bird snake will never snap a branch and plummet to the hard forest floor, nor let its mind wander and fall down. If faced with a choice of escape, upwards into trees or downwards into a dark burrow, they’ll take upwards any day. Thelotornis kirtlandii lives only south of the Sahara, as sand dunes are probably their greatest fear.
Bird snakes like the ground, but they love being in trees. The venom delivery is rear-fanged, and they struggle to inject more than mere droplets without extensive chewing, but the venom is moderately pro-coagulant. If you see one plummeting toward your face, getting larger and larger, you’re not about to die; just rip away the snake before it can begin to chew on your nose.
Trivia: Thelotornis kirtlandii was named after the same scientist who named the Kirtland’s snake of Ohio (a non-venomous meadow lover).
| 7 | Keeled slug snake |
A 50-60cm Thai species which actually eats slugs rarely, focussing on snails, which it sucks from their shells, gripping them using a deliberately imbalanced jaw. Keeled slug snakes (Pareas carinatus) range from Java to Vietnam and are the most abundant of the Pareas slug-eating family.
It’s common to see this snake intertwined with a thin branch, with jungle colours that almost resemble a tiny alien creature. They’d stand no chance in a war with monocled cobras and oriental ratsnakes, and that’s why they’ve chosen their humble snail niche instead. Keeled slug snakes are almost always found on branches, usually 1-2 metres above ground, They stray to the ground occasionally, but their snail prey is much more visible on branches, as they slime and grind along.
Keeled slug snakes rest on incredibly thin branches like a tightrope walker, applying several spaghetti coils for support. Their perspective is different, as the branches only look tiny to us humans. To Pareas carinatus, they look as welcoming as a small footbridge across a stream – perfectly easy to navigate with the slightest concentration.
| 8 | Annulated cat-eyed snake |
An extremely common tree snake of South America. Leptodeira annulata has a mild venom capable of swelling a hand, if they stay attached too long, and are recognisable by orange colours and bulging eyes, without being as bizarrely proportioned as the blunt-headed tree snake. This species derives 90% of its meals from frogs, including red-eyed tree frogs and Cei’s white-lipped frogs.
In 2005, scientists ventured to the Pantanal wetland region of southwest Brazil to gather some technical data. They found that the local Leptodeira annulata spent over 85% of their time in trees, and 3% on the ground. By day, they slept in hollows within tree trunks, and their meals consisted of frogs on branches, and frog spawn clusters hidden in tree hollows.
Every aspect of their life is adapted to trees. Leptodeira annulata has the usual thin body to reduce height on fragile branches, and large eyes for scanning its tangled branch ecosystem. Annulated cat-eyed snakes are found in deep jungles, but also tree clumps in villages and next to rivers.
| 9 | Pirmad catsnake |
The Boiga catsnake family has 38 members. Brown tree snakes originate in Australia, while green catsnakes control Thailand. The Pirmad catsnake (Boiga dightoni) is a species of India’s western Ghats mountains, a range of damp hilly forests, and many bizarre species. This is a branch dweller, which can stray to the ground, but much prefers to be draped around a tree climb 1-5 metres high.
Pirmad catsnakes have a poorly researched venom, which is believed to be mild like the rest of their family. They’re no threat to humans, whether a tree-climbing child or a cameraman who inches too close. Boiga dightoni is neither too slow or fast, moving slowly yet elegantly through their home tree. If you’re midway through climbing a tree, then Boiga dightoni isn’t fast enough to dash over and sink their fangs in.
You can find common catsnakes in trees up and down India, from the western Ghats to Himalayan foothills. Their diet includes reptiles such as oriental garden lizards, and they likely fall prey to roving birds. Sticking to branches has one disadvantage: no access to burrows and the dark shelter they offer. However, branches are a decent safety perch against fellow serpents like Indian kraits and Indian cobras, which can climb trees, but not so effortlessly that they can swallow a catsnake which is fully adapted to them.
| 10 | Eyelash viper |
This venomous snake chose tree branches millions of years ago, and is now fully adapted to them. Eyelash vipers (Bothriechis schlegelli) measure 40-80cm and are very common, ranging from Guatemala to Ecuador. Here, they coexist with fer-de-lances and Central American bushmasters, but while they stick to the ground, Bothriechis schlegelli is an arboreal viper, preferring perches 1-2 metres high. They effortlessly coil around thin branches, remaining stationary in ambush position, and springing forward in propulsive force when prey wanders past.
Eyelash vipers don’t kill scores of people, but bites aren’t rare either. Forests near plantations are a danger zone, and the plantations themselves. Unlike a coral snake, eyelash viper venom is almost completely free from neurotoxins. In typical viper fashion, they specialise in cytotoxins (necrosis, swelling) and haemotoxins (spontaneous bleeding).
Eyelash vipers have the power to attack you from a branch, striking the chest rather than ankles or shins. They also have the power to attack you from a fruit box. By lurking in banana trees, eyelash vipers are sometimes wrapped up in crates and shipped thousands of miles overseas.