Did You Know Black Iguanas Sometimes Eat Juveniles?
© Flávio H. G. Rodrigues
Herpetologists Flávio H. G. Rodrigues, Jose Mora, Lucia I Lopez and Luis D. Alfaro were doing field work in Playa Naranjo in Costa Rica on the black iguana in August 2014 when they happened upon an adult female black iguana (Ctenosaura similis) pursuing and grabbing a three month old juvenile Ctenosaura similis. The incident occurred on a sunny day right before noon. In response, the juvenile bit the fingers of the larger female.
According to the researchers, drought may have played a factor in the attack as it occurred during an El Niño, and food sources in the park were scarce. They believe that the drought conditions caused the larger black iguana to resort to cannibalism as the usual insect and plant resources that are staples of the lizard were in scarce supply.
They noted just five other instances of the black iguana resorting to cannibalism with just a single event caused by extenuating circumstances. That event was an adult female eating a new hatchling iguana. They do not know if adult black iguanas feed on juveniles on a regular basis but characterize it as an opportunistic feeding event. The conditions and the nutritional benefits for the adult iguanas and the potential for a high mortality of juvenile iguanas due to the drought conditions for that season of the year favor cannibalism, they surmise. They believe that the probability for continued cannibalism decreases later in the year as the juveniles move to other regions of the park in which the adults don’t venture.
John B. Virata keeps a western hognose snake, a ball python, two corn snakes, a king snake, and two leopard geckos. His first snake, a California kingsnake, was purchased at the Pet Place in Westminster, CA for $5. His first pet reptile was a green anole that arrived in a small box via mail order. Follow him on Twitter @johnvirata