The captivating Cape cobra

Hi everyone! My name is Molly, and I am a Herpetology Keeper here at Zoo Atlanta. While we have many amazing animals in our Scaly Slimy Spectacular building, I am going to talk about one of our most iconic animals … the cobra!

Zoo Atlanta has had many different species of cobras over the years; however, our current star is a Cape cobra (Naja nivea). Cape cobras are found in South Africa, typically in arid regions. These snakes are crepuscular (active around dusk and dawn) in the summer months and diurnal (active during the day) the remainder of the year. Cape cobras are generalist predators, meaning that they have a broad diet and feed opportunistically. It has been recorded that Cape cobras consume reptiles, amphibians, birds/eggs, and mammals, with other snakes making up a large portion of their diet. Chicks and eggs are also regularly consumed.

In the animal kingdom, it is not uncommon to see male and female animals of the same species have different physical characteristics; this is called sexual dimorphism. While Cape cobras do express sexual dimorphism, it is very subtle. Both male and female snakes tend to have similar body sizes; however, males tend to have larger heads and longer tails (measured from the vent to the tail tip). The breeding season for these snakes usually occurs in the warmer months (August to January). Cape cobras are oviparous, meaning that they are egg layers and can lay anywhere from eight to 20 eggs in a clutch. After laying eggs, the mother will guard the nest until the offspring hatch. When threatened, cobras can form a hood as a warning display. They have specialized ribs in the neck and several sets of muscles that allow them to perform this action. 

One of the greatest tools a cobra has is its venom. Cape cobra venom is classified as neurotoxic (affecting the nervous system and motor function); however, it is a combination of neurotoxins and cytotoxins (toxins that damage or destroy cells) with neurotoxins making up most of the venom. If envenomation occurs, this venom is said to cause respiratory failure and fatal paralysis. Studies conducted to examine the breakdown of the venom have established over 80% of the venom is made up of α- neurotoxins, cytotoxins/cardiotoxins and weak neurotoxins. α- neurotoxins are strongly correlated to the lethality of the venom but only make up about 7.4% of the total venom proteins. Cardiotoxins (these lead to potentially deadly heart conditions), also known as cobra cytotoxins, make up most of the total venom proteins measuring at about 75.6%. Due to the potential risks of caring for snakes like this, zoological institutions like Zoo Atlanta participate in the Association of Zoos and Aquariums (AZA) antivenom index to ensure all individuals have access to antivenom in the event of an emergency. We also maintain a supply of antivenom here.

Although the Cape cobra is one of southern Africa’s most common snakes, it stands out due to its impressive hooding, potent venom, and cannibalistic tendencies. While dangerous, these snakes play an important role in their ecosystem by managing the populations of prey animals. With awareness and respect, we can conserve and protect these animals. I hope you enjoyed learning about Cape cobras, and I look forward to seeing you all visit ours soon!

Molly K.
Keeper I, Herpetology