The black-necked spitting cobra (Naja nigricollis ) is a species of spitting cobra found mostly in sub-Saharan Africa. They are moderately sized snakes that can grow to a length of 1.2 to 2.2 m (3.9 to 7.2 ft) in length. Their coloration and markings can vary considerably. They prey primarily on small rodents. They possess medically significant venom, although the mortality rate for untreated bites on humans is relatively low (~ 5–10%, in endemic regions under 1%). Like other spitting cobras, they can eject venom from their fangs when threatened (one drop over 7 metres (23 ft) and more in perfect accuracy). The neurotoxic venom irritates the skin, causing blisters and inflammation, and can cause permanent blindness if the venom makes contact with the eyes and is not washed off.
Naja nigricollis belongs to the cobra genus Naja under the family Elapidae. It previously included two subspecies that have been moved to the species Naja nigricincta – the zebra spitting cobra (Naja nigricincta nigricincta ) and the black spitting cobra (Naja nigricincta woodi ).
The Black-necked spitting cobra is a species of spitting cobra found mostly in sub-Saharan Africa. Its color can vary depending on the region. Some specimens are black or pale grey with a yellow or reddish ventral side with a broad, black neck band, often with an orange or pinkish bar on the neck. Other specimens can be yellowish-brown or have a yellow copper color and are missing the bandings around the neck and the reddish color on the belly. Some other specimens are deep reddish-brown, and yet others are olive-brown. Some can even be striped black and white or totally white (with dark eyes). Black-necked spitting cobras have medically significant venom, and like other spitting cobras, they can eject venom from their fangs when threatened; one drop typically reaches over 7 meters (23 ft) and even more in perfect accuracy.
Black-necked spitting cobras are very common and widespread in western, eastern, central, and parts of southern Africa. They occur in Angola, Benin, Burkina Faso, Cameroon, Central African Republic, Chad, the Democratic Republic of the Congo (except in the center), Congo, Ethiopia, Gabon, Ghana, Guinea Bissau, Guinea, Ivory Coast, Kenya, Liberia, Mali, Niger, Nigeria, Senegal, Sierra Leone, Gambia, Mauritania, Sudan, Tanzania, Somalia, Togo, Uganda, Zambia. These snakes typically inhabit savanna and semi-desert regions of Africa but they can also be found in moist savanna and cleared former forest regions, particularly near rivers and streams. In southeastern Nigeria, Black-necked spitting cobras occur in man-made farmlands, plantations, suburban areas, and a few fragmented forests. They also live in coastal scrubs and dry grasslands and are also common in villages or small towns where they may come in direct contact with people.
Black-necked spitting cobras are solitary creatures. They can be either nocturnal or diurnal depending on the time of year, geographic location, and average daytime temperature. This adaptability allows them to better regulate their body temperature and to gain access to the most abundant food sources of a particular area. Black-necked spitting cobras may find abandoned termite mounds or rodent holes to hide or cool off. However, tree trunks seem to be their favorite hiding places. They are excellent tree climbers and can be arboreal at times. Black-necked spitting cobras are known for their ability to project venom at a potential threat; they readily spit venom and bite with only the slightest provocation. Black-necked spitting cobras are sometimes found in captivity, and wild-caught individuals are generally nervous and prone to spitting. Captive-bred animals tend to be much more docile and calm when compared to their wild-caught counterparts.
In 1944, writing as Major Harold Ridley, the English ophthalmic surgeon published a short paper in the British Journal of Ophthalmology on spitting snakes and an account of the composition and action of snake venom in general. From his own experiences in wartime Ghana, then known as the Gold Coast, Ridley described snake venom ophthalmia in a 30-year-old labourer named Gogi Kumasi, who was cutting grass when a Black-necked cobra raised its head from the grass and forcibly spat venom toward the man's right eye from a four- or five-feet distance. Ridley treated the man and followed his case until the eye had fully recovered – after about a week. In conclusion, after discussion on the therapeutic uses of snake venom, he conjectured that in the future diluted venom or a constituent of venom might be used as a powerful anaesthetic in some cases of ophthalmic surgery.
spitting snakes and an account of the composition and action of snake venom in general. From his own experiences in wartime Ghana, then known as the Gold Coast, Ridley described snake venom ophthalmia in a 30-year-old labourer named Gogi Kumasi, who was cutting grass when a Black-necked cobra raised its head from the grass and forcibly spat venom toward the man's right eye from a four- or five-feet distance. Ridley treated the man and followed his case until the eye had fully recovered – after about a week. In conclusion, after discussion on the therapeutic uses of snake venom, he conjectured that in the future diluted venom or a constituent of venom might be used as a powerful anaesthetic in some cases of ophthalmic surgery.
Black-necked spitting cobras are carnivores. Their diet includes primarily small rodents, such as small rats and mice, birds, and fishes, but they will also eat lizards, eggs, and even other snakes.
Black-necked spitting cobras are oviparous meaning they lay eggs. Their mating season can vary from the end of winter (September) to the beginning of summer (December). Usually, the mating season is the same whether in captivity or in the wild. Females commonly lay 10 to 15 eggs but can lay anywhere between 8 and 22 eggs at a time. The incubation period lasts about 90-100 days, but once the eggs are laid, they hatch in 60-70 days and need to be at a temperature of 28-30 °C (82-86 °F). At birth, the young are about 20 to 25 centimeters (7.9 to 9.8 in) in length and are completely independent.
There are no major threats to Black-necked spitting cobras at present.
Presently, the Black-necked spitting cobra is not included in the IUCN Red List and its conservation status has not been evaluated.