Jameson's Mamba
Dendroaspis jamesoni
Population size
Life Span
9 years
m ft 

Jameson's mamba (Dendroaspis jamesoni ) is a species of highly venomous snake native to equatorial Africa. A member of the mamba genus, Dendroaspis, it is slender with dull green upper parts and cream underparts and generally ranges from 1.5 to 2.2 m (4 ft 11 in to 7 ft 3 in) in length. Described by Scottish naturalist Thomas Traill in 1843, it has two recognised subspecies: the nominate subspecies from central and west sub-Saharan Africa and the eastern black-tailed subspecies from eastern sub-Saharan Africa, mainly western Kenya.

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Predominantly arboreal, Jameson's mamba preys mainly on birds and mammals. Its venom consists of both neurotoxins and cardiotoxins. Symptoms of envenomation in humans include pain and swelling at the bite site, followed by swelling, chills, sweating, abdominal pain and vomiting, with subsequent slurred speech, difficulty breathing and paralysis. Fatalities have been recorded within three to four hours of being bitten. The venom of the eastern subspecies is around twice as potent as that of the nominate subspecies.

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Pursuit predator








Not a migrant


starts with


Jameson's mamba is a large quick, and highly venomous snake native to equatorial Africa. Adults are usually dull green across the back, blending to pale green towards the underbelly with scales generally edged with black. The ventral side, neck, and throat are typically cream or yellowish in color. Populations that are typically found in the eastern part of the range, feature a black tail, while central and western examples typically have a pale green or yellow tail.



Jameson's mambas occur mostly in Central Africa and West Africa, and in some parts of East Africa. In Central Africa, they can be found from Angola northwards to the Democratic Republic of Congo, Republic of Congo, Central African Republic, and as far north as the Imatong Mountains of South Sudan. In West Africa, they range from Ghana eastwards to Togo, Nigeria, Cameroon, Equatorial Guinea, and Gabon. In East Africa, they can be found in Uganda, Kenya, Rwanda, Burundi, and Tanzania. These snakes inhabit rainforests, woodland, and forest-savanna. Jameson's mambas are adaptable creatures and may occur in areas where there has been extensive deforestation and human development. They are often found around buildings, town parks, farmlands, and plantations.

Jameson's Mamba habitat map

Climate zones

Jameson's Mamba habitat map
Jameson's Mamba
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Habits and Lifestyle

Jameson's mambas are highly arboreal and agile snakes that come down to the ground only to bask or move to another tree. They are solitary and interact with each other only during the mating season. Jameson's mambas are active diurnal hunters and chase prey, similar to other mamba species. When prey is caught, mambas will strike until the prey dies. When these snakes feel threatened they will flatten their neck in mimicry of a cobra, and their body shape and length give an ability to strike at significant range. Jameson's mambas are not typically aggressive in nature and will almost always attempt to escape.

Seasonal behavior


Jameson's mamba is classified as a Snake of Medical Importance in Sub-Saharan Africa by the World Health Organization, although there are few records of snakebites. Field observations over a 16-year period in the Niger Delta in southern Nigeria found that both humans and snakes were most active in rural areas during the rainy season, April to August, hence rendering this a peak period for snakebite. As well as succumbing to snakebites, workers were reported to have perished from falling from trees after encountering Jameson's mambas in the canopy of trees in palm oil plantations. Snake bites are rare in cities but more common in forested areas in countries such as the Democratic Republic of the Congo; the country's poor infrastructure and lack of facilities render access to antivenom difficult.

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Like other mambas, the venom of the Jameson's mamba is highly neurotoxic. Symptoms of envenomation by this species include pain and swelling of the bite site. Systemic effects include generalised swelling, chills, sweating abdominal pain and vomiting, with subsequent slurred speech, difficulty breathing and paralysis. Death has been recorded within three to four hours of being bitten; there is an unconfirmed report of a child dying within 30 minutes. With an average intravenous murine median lethal dose (LD50) of 0.53 mg/kg, the venom of the eastern subspecies kaimosae is more than twice as potent as that of the nominate subspecies jamesoni at 1.2 mg/kg. The reason for this is unclear as the venom compositions are similar between the two subspecies, though kaimosae has higher concentrations of the potent neurotoxin-1.

Similarly to the venom of most other mambas, Jameson's mamba's contains predominantly three-finger toxin agents as well as dendrotoxins. Other toxins of the three-finger family present include alpha-neurotoxin, cardiotoxins and fasciculins. Dendrotoxins are akin to kunitz-type protease inhibitors that interact with voltage-dependent potassium channels, stimulating acetylcholine and causing an excitatory effect, and are thought to cause symptoms such as sweating. Unlike that of many snake species, the venom of mambas has little phospholipase A2. Although cardiotoxins have been isolated in higher proportions from its venom than other mamba species, their role in toxicity is unclear and probably not prominent.

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Diet and Nutrition

Jameson's mambas are carnivores and since they spend most of their time in trees birds make up a large portion of their diet. Other prey items include small mammals such as mice, rats, and bats, and small lizards.

Mating Habits

1-17 eggs

Jameson's mambas are oviparous and lay up to 17 eggs. During the breeding season, males fight each other and locate females by following their scent trails.


Population threats

There are no known threats that face Jameson's mambas at present.

Population number

Presently, Jameson's mamba is not included in the IUCN Red List and its conservation status has not been evaluated.


1. Jameson's Mamba on Wikipedia - https://en.wikipedia.org/wiki/Jameson%27s_mamba

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