Black mambas: heavy metal pollution detectors

According to researchers, toxic material builds up in snake scales, and thus black mambas can be good indicators of heavy metal pollution. Zoologist Cormac Price speaks about some of their findings.

- By Cormac Price, Marc Humphries, Graham Alexander, and Nick Evans

Black mambas (Dendroaspis polylepis) are Africa's longest, most well-known venomous snakes, but despite their fearsome reputation, these misunderstood snakes are vital players in their ecosystems.

They keep rodent populations in check and, in turn, help to protect crops and limit the spread of disease. The species is found widely across sub-Saharan Africa, from Senegal to Somalia and southwards into South Africa. They are capable of adapting to many environments.

HOW DO BLACK MAMBAS INDICATE TOXIC POLLUTION?

It is about bioaccumulation. Bioaccumulation happens when chemicals, like pesticides or heavy metals, build up in an organism's body. These toxins come from polluted environments, especially from waste products of human activities like manufacturing. They pollute water or soil and gradually accumulate in plants and animals.

If toxins are present in the environment, they may first be taken in by plants, and then by animals that eat those plants, and animals that eat those animals.

SNAKES WARN US OF THE INCREASING DANGER POLLUTANTS POSE TO ENVIRONMENTAL AND HUMAN HEALTH

Black mambas are quite high up the food chain, so a lot of the toxins would accumulate in their bodies. These poisonous substances can reach dangerous levels, causing health problems to whatever eats them.