A Significant Blue Birth

The San Diego Zoo’s Applied Animal Ecology Division is pleased to announce the hatching of a critically endangered Grand Cayman blue iguana Cyclura lewisi. This little female iguana hatched out of her egg on September 13, 2008, after an incubation of 92 days at 86.5 degrees Fahrenheit (30.3 degrees Celsius). She weighed only 1.58 ounces (45 grams) at hatching—a tiny little girl compared to males of her species that can grow to over 18 pounds (8 kilograms) as adults! Although our little girl is gray in color now, as most hatchlings are, adults of the species can become a beautiful powder blue color.

This iguana was a very lucky animal. About three-quarters of the way through incubation, her egg formed a small crack and started to leak fluid. This is a rare occurrence and can be caused by too much humidity, a thin shell, or many other factors. I patched the shell with plastic wrap and tissue glue and crossed my fingers. A few weeks later, I got the word that the iguana had hatched, and I ran over to the incubator room to see her. She looked good, although she had a distended belly, which usually means she hatched a bit too early and wasn’t able to absorb all of her yolk. I took her to the vets at the Harter Veterinary Medical Center, and due to the distended belly and a slight injury to the eye that probably happened during hatching, we decided she would stay with the vets. Internal yolk can usually absorb on its own as long as the animal is kept quiet and warm, but sometimes it can become infected and can even be lethal. After a week of excellent veterinary TLC, the little iguana absorbed her yolk, and her eye was healed up. She is currently waiting to be housed in the new iguana building that is near completion in an off-display area of the Wild Animal Park (stay tuned for that blog!).

Grand Cayman iguanas are considered to be the most endangered lizard in the world. Loss of habitat, introduced predators, feral animals that compete for resources, and cars all contribute to the iguana’s decline. At one point, there were as few as 20 animals left on Grand Cayman, but thanks to captive breeding, headstart and release protocols, and a new reserve system on the island, Grand Cayman iguanas are slowly starting to repopulate the wild.

Jeff Lemm is a research coordinator for the San Diego Zoo. Read Jeff’s previous blog, Frog Blog—What’s Hoppenin’?