Michael Avery and colleagues (2010) at the USDA Animal and Plant Health Inspection Service in Gainesville, Florida have produced a new report published in Biological Invasions online on 22 April. They housed three female and six male Burmese Pythons at their facility. The snakes were held in outdoor cages made of an aluminum frame with plastic coated wire. Each cage contained a hide box that contained a heat producing mat. When the outside temperature was 5.7 to 9ºC the heat mat was at 26.7ºC. During the January cold spell three of the nine snakes died, two others developed infections and were eventually euthanized and two others exhibited signs of respiratory distress but were treated for the infection. Thus, seven of the nine snakes died or would have died without human intervention during the cold spell. The authors concluded that cold weather may well be a limiting factor in the dispersal of the snakes out of Florida.
Avery, M. L. et al. 2010. Cold weather and the potential range of invasive Burmese Pythons. Biological Invasions doi 10.1007/s10530-010-9761-4