What does the anaconda eat?

Have you ever wanted to know more about what anacondas eat? Well our Advisory Committee member Steven Allain and his colleague decided to dig deeper and find out more!

Anacondas, a group of snakes that are infamous for their size and the myths that they consume people. One day, my colleague Oliver Thomas and I were curious to see whether or not there was any truth in the claim. We scoured the internet for verified claims of anacondas having eaten people, whilst also collecting data from published scientific articles on the diets of anacondas. Contrary to popular belief, there are four species of anaconda with the Bolivian and dark-spotted anacondas being less common and widespread than the green and yellow anacondas. This made our review slightly harder as there is a strong bias in the number of published prey items for the green and yellow anacondas, compared with the less common species. Something that confounds this further is that the Bolivian anaconda was only described in 2002, so there hasn’t been as long for dietary observations to accumulate, as is the case with the green anaconda, with over 100 years of dietary observations available.

Through this project, we’ve been able to compile all of the known information (that we could find) within the primary literature, on the diets of anacondas. We were unable to find a single instance where an anaconda had consumed a person, which is what we expected. However, you never know what the results are going to be when you undertake a project like this. With the data collected, we were also able to demonstrate that the diet of anacondas shifts as the snakes grow, although this is still to be confirmed through more rigorous study than just a review of the literature. Logically though, it does make sense. Smaller snakes are limited by the size of their skulls as to which prey they can feed on, as they grow, they can eat larger and larger animals. It’s clear from our analysis that anacondas have a broad diet and this is most likely linked to the fact that they are opportunistic feeders.

If you’d like to read their review, you can do so here. Whilst contributing to the knowledge of these snakes, Steven and Oliver also hope that it will assist in dispelling the legends and myths that they attack and eat people. They have also identified areas where research is still lacking, which will hopefully allow researchers and conservationists to better understand these animals in the future.