In nature, many animals play with each other, it is a widely common phenomenon. But sometimes it still surprises us, such as when researchers studying dolphins in a Bolivian river (in the Beni floodplains of Bolivian Amazonia), captured them playing with Beni ananconda snake in their mouths. These photographs were taken near the Tijamuchi River in Bolivia, in August 2021.
These river dolphins are rarely seen with their heads above the water and it is not exactly clear what exactly was going on. However, “Cetaceans frequently exhibit interesting and complex play repertoires, often socially, that likely have developmental and societal roles”, say the researchers.
This time the researchers saw a group of dolphins staying above the water for longer than usual, and they took the photos to try to understand what was going on. After reviewing the photos they understood what was going on.
“After checking on the first images we realized that a snake was handled by them, and while it was difficult to estimate their group size, there were at least six of them,” the researchers write in a paper. “It became clear that they rather were playing with the snake than trying to eat it.”
The Beni anaconda E. beniensis is a large sized aquatic Boid snake that can grow up to 2 meters in length. The Bolivian river dolphins I. boliviensis are large-sized fresh water mammals, that can reach up to 2.4 meters. Both are endemic to the floodplains of Bolivian Amazonia. The dolphins are threatened with extinction as their populations decline due to over-fishing, hunting, and habitat loss. In the Tijamuchi River, there are estimated to be 0.52 dolphins per kilometer in both dry and wet seasons.
The played around with the snake in different ways, moving around 70-80 meters or 230-262 feet downstream during the observations that lasted 7 minutes. The dolphins could be playing with the snake, or trying to eat it. Perhaps it was social-sexual behaviour.
“Afterwards, we were able to observe on the photographs that the adult males were sexually aroused while engaging in object play with the anaconda,” write the researchers in their study.
“There were juveniles on the scene as well, and it seemed that the adults were showing off the snake to them.”
Sadly, the snake probably died due to the interaction.
Here is the Study.