WEDNESDAY, July 22, 2015 (HealthDay News) -- Boa constrictors kill their prey by constricting their blood flow, not by suffocation, a new study shows.
The study, published July 22 in the Journal of Experimental Biology, challenges the long-held belief that constrictors kill their prey through suffocation.
As the snakes squeeze their victim, blood supply to the heart, brain and other vital organs is cut off. The victims become unconscious in a few seconds and die faster than if they were being suffocated, the researchers reported.
The scientists measured a live rat's blood pressure while it was being constricted by a boa. The rat was anesthetized so that it did not feel pain or suffer, they noted. The rat's blood circulation shut down within seconds after the snake began to squeeze.
"I remember being in the room and the students were looking at the data in disbelief that it happened that fast. We could see the arterial pressure go down, the venous pressure go up and we could see this right when the snake was doing it [squeezing]," Scott Boback, of Dickinson College in Carlisle, Penn., said in a journal news release.
An animal caught in a boa's coils likely passes out within seconds, before other major organs begin to fail, Boback added.
The National Zoo has more about boa constrictors.