Article Review: Factors that can influence the survival rates of coral snakes (Micrurus corallinus) for antivenom production

In Brazil, nearly 20,000 people are envenomated by a venomous snake each year, 1% of those being bitten by a coral snake (Mendes, 2019).  The push for increased conservation efforts over the last few decades (however vital to the maintenance of natural biodiversity) has drastically decreased the number of coral snakes that are donated/ discovered by the Laboratory of Herpetology at Instituto Butantan. Here, they have been focusing on improved methods for maintaining the captive population present at the lab.  This has proved very difficult since Micrurus corallinus has been found to be particularly susceptible to diseases and often have a difficult time adjusting to captive life.  The article sites information from personal interviews stating that the number of snakes obtained by the lab has dropped from approximately 250 snakes a year in 1995 to only approximately 35 snakes over the past few years.  The author focused on the utilization of several different substratum used as a habitat for the individual snakes as well as their diet/ food preparation.

The author collective data obtained over the last 20 or so years to narrow down the method changes that have brought about the biggest improvement to the longevity of the captive snakes.  The first substratum used was sphagnum moss (Group I & II).  This material was found to be harmful to the snakes since it retained to much humidity and lead to bacterial infections and high mortality rates among the colony.  The author noted a large increase in longevity when they switched to bark as a substratum (Group III), since it retained a lower, more optimal humidity. 

The second point that the author studies was the diet of the snake.  Originally, the snakes were fed live animals caught in the wild (Group I).  This presented challenges since the animals were vectors for many parasites and diseases that heavily impacted the first group of snakes.  There was a switch to euthanizing the prey and freezing it to reduce the number of parasites and this helped drastically improve the longevity of the snakes.  Finally, the lab began to feed the snakes captive bred corn snakes (Pantherophis guttatus) since they are easily bred and maintained and also increased the predatory behavior of the snakes (since the were live food) (Group II & III). This further improved the survival rates of the snakes.

The author states that the first group of snakes had the highest mortality rate out of the three groups, stating that only 10% of the snakes survived after the first 150 days in captivity.  Group II was calculated at 40% survival after 150d, and Group III had the highest at 75% survival after 150d.  This is dependent most of the control of disease through the captive bred food and use of bark as a substratum (Mendes, 2019).

This research is important as society is trying to find a balance between the demands of human survival and the survival of natural resources that surround us.  Many people is underdeveloped areas are largely affected by the number of snake bites they endure so it is critical to maintain enough antivenom to counteract this number.  That being said, it is vital to maintain the natural population and environment of snakes in the wild.  That is why improved methods of maintating a captive population of coral snakes for antivenom production is so vital, so that there can be a better balance between humans and nature.