Scientists have reported a case of cannibalism among giant iguanas. Perhaps the abnormal heat pushed the lizards to this behavior. Researchers from the National University of Costa Rica reported their observations in the journal Mesoamerican Herpetology.
Cannibalism is a fairly rare phenomenon among reptiles, and especially rarely, scientists manage to observe it with their own eyes. This opportunity was presented to the authors of the article when they worked in the Santa Rosa National Park in northwestern Costa Rica.
Young black iguanas feed on insectivores, while adults sometimes eat birds. When kept in captivity, iguanas are fed a diet that consists of 95% plant foods and 5% animals.
On August 17, 2014, scientists noticed a meter-long adult female black iguana (Ctenosaura similis) chasing a representative of her own species about 3 months old. The victim tried to fight back with her paws, but she failed to escape from the mouth of the attacking lizard.
According to experts, due to El Niño, fluctuations in water temperature in the Pacific Ocean, August 2014 turned out to be extremely hot and dry, while it usually rains in Costa Rica at this time of the year. Abnormal weather caused a shortage of food resources, so adult iguanas switched from insects and plants to their younger relatives.
Cannibalism may have also been the iguanas' response to overpopulation. We will remind, recently paleontologists found out that predatory dinosaurs-theropods, who lived at the end of the Cretaceous period in Canada, fiercely fought among themselves and did not disdain the bodies of their dead brothers.